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Jordan Journal of Mechanical and Industrial Engineering
ISSN: 1995-6665
JJMIE Volume 15
JJMIE Volume 15
Complete Journal
High Quality Print Web Viewing
Number 1 
Number 2 Number 3 Number 4 Number 5
Dandan Liu, Shigang Li, Hui Liu.
Abstract: With the further increase of domestic oil demand, the diversification strategy of energy supply represented by alternative energy sources, such as alcohol fuel which has become a direction of China's energy policy. Alcohol fuel can reduce conventional engine emissions by replacing conventional gasoline and diesel, but their unconventional emissions -- formaldehyde -- tend to have higher concentrations than conventional engines. Based on this, this paper analyzed the physical and chemical properties of mixture of methanol and gasoline and its feasibility as an energy fuel, and conducted experiments on formaldehyde emission of gasoline and methanol gasoline respectively, and then obtained a large number of experimental data that studied and analyzed the experimental results and methods, and drew relevant research conclusions. The results show that the high ratio of alcohol fuel can replace the use of chemical fuel and has good energy saving and environmental protection characteristics. When the same fuel is tested, the formaldehyde emission increases first and then decreases with the increase of power. In this paper, a large amount of formaldehyde emission data from alcohol fuel engines are obtained through bench experiments, which provides a scientific basis for the future development of alcohol fuel vehicle combustion system and the formulation of environmental emission standards.
Keywords: engine, alcohol fuel, methanol, unconventional emission, formaldehyde;
Zhenqi Yu, Huifang Jia, Xingyuan Huang
Abstract: An electric SUV is designed and developed based on the original traditional fuel vehicle model. The design scheme of the front suspension lower control arm of prototype vehicle is referred to save the development cycle and cost of the design. The original design scheme is optimized to meet the performance and lightweight requirements. In this paper, the analysis model of lower control arm is firstly established based on the finite element technology to conduct free modal analysis. The results show that the first two modes appear as bending and torsion. The modal frequency is higher than excitation frequency, which satisfies the requirement of vibration characteristics. Then free modal test on lower control arm is carried out based on hammer method, and the test results show that the accuracy of the analysis value is high. Then, the front suspension dynamics model of electric SUV model is established to extract the load of lower control arm. The inertial release method is applied to analyze its limit strength, the results show that its maximum stress is lower than its used stress which meets the requirements of strength design. Finally, the multidisciplinary optimal design of lower control arm is carried out to obtain the best design scheme. After optimization, both modal characteristics and strength characteristics meet the design requirements, and its mass is reduced by 16.7%. And its optimization scheme has passed the bench test and road test certificate successfully, so it has high accuracy and feasibility, providing a new idea for the design and development of the lower control arm, the front suspension of electric SUV.
Keywords:lower control arm; modal; inertia release; strength; optimization; bench test;
Accurate Modeling and Numerical Control Machining for Spiral Rotor of Double Rotor Flowmeter
Chunyan Tian, Hai Jiang, Chaochao Chen
Abstract: Aiming at the design and manufacturing problems of the spiral rotor of dual-rotor flowmeter, the profile characteristics and forming principles of the spiral rotor are analyzed, and the function equation of its cross-section profile curve is derived. Based on the analysis, a mathematical model for machining screw rotor with spherical milling cutter is established and the accurate three-dimensional modeling of spiral rotor parts is realized by using UG software. The simulation of the two rotors proves that the modeling method is reasonable and effective. Then using automatic programming and manual programming methods, a multi-axis NC machining program for the parts is written. The macro variable is introduced for the main program to call many times, which greatly simplifies the program structure, reduces the amount of program, and is easy to modify. The NC machining experiment of the spiral rotor with a standard ball-end milling cutter on a four-axis milling machining center is conducted. The results show that the screw rotor machined by the mathematical model has good quality. This programming and manufacturing method is very suitable for processing spiral rotors in multi-variety small batch production, and thus a high machining accuracy can be achieved.
Keywords:spiral rotor; functional equation; digital modeling; NC programming; multi-axis simultaneous machining;
Chunhui Liu, Kechuan Yi
Abstract: The effects of exhaust gas recirculation (EGR) rate on homogeneous charge compression ignition (HCCI) combustion and emission of free-piston diesel engine generator (FPDEG) was investigated by using a three-dimensional (3-D) computational fluid dynamics (CFD) model of FPDEG. In the 3-D CFD model of FPDEG, the diesel mechanism with 109 species and 543 reactions was incorporated into the combustion model, and the soot and NOx production were calculated by Hiroyasu-NSC model and 12 steps NOx model. The simulation results showed that the EGR rate had great influence on the HCCI combustion and emission performance of FPDEG. As the EGR rate was changed from 0 to 10%, the HCCI combustion phase of FPDEG slightly lagged, the peak value of heat release, the maximum in-cylinder temperature and pressure and the NOx content significantly decreased, but SOOT content increased. When the EGR rate was 20%, the HCCI combustion of FPDEG was incomplete, and the UCH, SOOT and CO content all obviously increased.
Keywords:Free-piston diesel engine generator, Homogeneous charge compression ignition, diesel mechanism, exhaust gas recirculation;
Space Trajectory Planning of Electric Robot Based on Unscented Kalman Filter
Chang Kuang, Xiaoyi Zheng
Abstract: Abstract: The effects of exhaust gas recirculation (EGR) rate on homogeneous charge compression ignition (HCCI) combustion and emission of free-piston diesel engine generator (FPDEG) was investigated by using a three-dimensional (3-D) computational fluid dynamics (CFD) model of FPDEG. In the 3-D CFD model of FPDEG, the diesel mechanism with 109 species and 543 reactions was incorporated into the combustion model, and the soot and NOx production were calculated by Hiroyasu-NSC model and 12 steps NOx model. The simulation results showed that the EGR rate had great influence on the HCCI combustion and emission performance of FPDEG. As the EGR rate was changed from 0 to 10%, the HCCI combustion phase of FPDEG slightly lagged, the peak value of heat release, the maximum in-cylinder temperature and pressure and the NOx content significantly decreased, but SOOT content increased. When the EGR rate was 20%, the HCCI combustion of FPDEG was incomplete, and the UCH, SOOT and CO content all obviously increased.
Keywords:Free-piston diesel engine generator, Homogeneous charge compression ignition, diesel mechanism, exhaust gas recirculation;
Keywords:Kalman filter; Electric robot; Space track; Mobile trajectory planning;
The Electric Vehicle Torque Adaptive Drive Anti-Skid Control Based on Objective Optimization
Yingqi He
Abstract: The vehicle is interfered by the lateral wind in the traditional anti-skid control method, which results in a bad anti-skid control effect of electric vehicle torque drive. For this reason, a method of torque adaptive drive anti-skid control for electric vehicle is proposed. In order to realize the driving force control of distributed driving electric vehicle, the driving motor is modeled and simplified. A battery model was established to analyze the influence of the bus voltage fluctuation on the motor torque response. The power system model is added to the existing vehicle model to complete the simulation model design of the distributed drive electric vehicle. According to the characteristics of the friction circle of the tire, the driving torque of the driving wheel is analyzed. In order to resist the influence of interference factors on vehicles during vehicle movement, through the concept of vehicle stability control, the left and right driving torque is dynamically adjusted by using the obtained ideal driving force distribution ratio of front and rear axles. The simulation results show that the proposed method can effectively increase the driving torque and improve the fitting coefficient of the driving anti-skid torque.
Keywords:Distributed drive; Drive skid control; Driving force distribution; Dynamical system modeling;
Ziying Liua, Tianlai Yu, Ning Yan, Zhihai Piao, Hongxiang Zhang
Abstract: In this paper, the cement concrete with low heat of hydration was prepared by adding fly ash, and then used in the double-cylinder insulation technology. Based on heat dissipation test, thermal conductivity test and low temperature strength test of the prepared concrete, the growth law of concrete strength under negative temperature condition was studied. The strengths of three concrete test piles at the corresponding temperature were measured by ultrasonic method, and the influence law of double-cylinder insulation technology on the change of concrete strength was studied. The results show that the curing temperature dropped from 20C to -3C, -5C and -7C on the 28th day. Compared with the standard curing temperature, the strength loss was 29.7%, 31.7% and 42.8%, respectively. There were similar rules on the 60th day and 28th day. In the first 7 days, the temperature of low hydration heat concrete was 1. ~2.8°C lower than that of ordinary concrete. From the 7th day to the 28th day, the temperature of low hydration heat concrete was 0.5°C higher than that of ordinary concrete. After applying the double-cylinder insulation technology to the concrete, the temperature was increased by 7.9°C, 7.3°C and 4.8°C in 0~3rd day, 3rd~7th day and 7th~28th day, respectively. Compared with strength on the 28th day, the strength of low-hydration heat concrete was 2.15% higher than that of ordinary concrete. After applying polyurethane insulation layer, the strength of the low-hydration heat concrete increased by 18.6% compared with that of the low-hydration heat concrete without insulation layer.
Keywords:negative temperature, concrete, low heat of hydration, heat preservation, temperature of foundation pile, strength;
Wear Properties of Aluminum Alloy 211z.1 Drilling Tool
Yong Liu, Lin He, Sen Yuan
Abstract: In the application process of China’s independently produced new aluminum alloy 211z.1 into high-end military and civilian industries, a great many holes are needed for fastening connection. However, the severe wear of the cutting edge of twist drill is an important factor that restricts the quality of hole processing and tool life. In this paper, the wear condition of the standard high-speed steel twist drill in drilling the new aluminum alloy 211z.1 is studied based on the drilling test, and the influence law of the drilling amount on the tool wear is revealed by designing a reasonable drilling test plan. The research results show that the cutting speed has a significant effect on the flank wear, and the drilling feed and the drilling height have relatively little influence on the flank wear of the tool.
Keywords:Aluminum Alloy 211z.1; High-speed Steel; Standard Twist Drill; Drilling Test; Flank Wear;
Calculation Method of Stiffness and Deflection of Corroded RC Beam Strengthened by Steel Plate
Qian Zhang, Huang Tang, Shihui Guo
Abstract: Abstract: In the application process of China’s independently produced new aluminum alloy 211z.1 into high-end military and civilian industries, a great many holes are needed for fastening connection. However, the severe wear of the cutting edge of twist drill is an important factor that restricts the quality of hole processing and tool life. In this paper, the wear condition of the standard high-speed steel twist drill in drilling the new aluminum alloy 211z.1 is studied based on the drilling test, and the influence law of the drilling amount on the tool wear is revealed by designing a reasonable drilling test plan. The research results show that the cutting speed has a significant effect on the flank wear, and the drilling feed and the drilling height have relatively little influence on the flank wear of the tool.
Keywords:Steel Plate, Corroded RC Beam, Strengthening, Stiffness, Deflection, Calculation Method.;
Electromechanical Coupling Model of AC Asynchronous Motor Drive System Based on Multiscale Method
Qiuping Pan, Jiaxiang Zhang
Abstract: Due to the development of motor drive system towards high power, integration and high-power density, this model cannot control mechanical vibration caused by electromechanical coupling. A new electromechanical coupling model of alternating current (AC) induction motor drive system is proposed. The transient characteristics of the motor were studied by multi-scale method, and the electromechanical coupling dynamic characteristics of the drive system were extracted. According to the dynamometer, the impact load is applied to the drive system, which causes the load on the inertial flywheel to suddenly increase by 3.5 times from 2500 Nm. The service coefficient of the realization shaft is defined as the ratio of the measured post-impact torque to the average pre-impact torque. The experimental results show that when the AC asynchronous motor's influence is passed through the electromechanical coupling model, the difference between the input and output shafts of the gearbox is minimal, and when the AC asynchronous motor's influence is different, the input and output shafts of the gearbox are maximum. It can be seen that the electromechanical coupling model established in this paper can control the mechanical vibration caused by electromechanical coupling and convert the internal load threat to the external load threat
Keywords:multiscale method; AC asynchronous motor; drive system; electromechanical coupling model;
Impact Evaluation of Industrial Energy Consumption Based on Input-output Complex Network
Ren Zhou, Xinhua Wang
Abstract: Target control and industrial transfer are important methods to regulate energy conservation and emission reduction in the region, so measuring the influence of each industry to energy consumption is the basis of regional industrial structure adjustment. Firstly, an energy flow network model is constructed based on the theory of Industrial Complex Network. It describes the mutual input and consumption of material and energy among industrial sectors. Then, the index system is designed to evaluate the influence of each industry on energy consumption in the economic system. According to the evaluation, methods are searched for to regulate energy-saving and emission-reducing on the industrial level. Based on the data of Shandong Province, the strategies of energy saving and emission reduction are put forward: research and develop new technologies; Sort management, focusing on the control of “key industries”, and paying attention to the industries that consume less energy but relevant more with others appropriately; Rational layout industry, optimize industrial structure and so on.
Keywords:energy consumption; energy flow network; Shandong province; evaluation of industrial impact;
A New Method to Analyze CNC Lathe Faults Based on Gutenberg–Richter Curve
Jie Yu, Zhiwei Zhu, Tiebin Wang, Yue Yao, Jiexiang Ding
Abstract: This paper collects and sorts out a large amount of fault data of a series of CNC lathes, and analyzes the fault data to classify fault levels. The values of a and b are obtained by Gutenberg–Richter (G-R) curve fitting, and then the relationship between a and b is used. The b value under each division criterion is obtained. By analyzing and comparing these b values, the rationality of classifying the fault levels according to these three methods is verified. The b-value is towards 1.0 when the reliability level of CNC lathes was promoted through ten years' reliability promotion.
Keywords: Gutenberg–Richter (G-R) curve; b value; CNC machine tool; fault level; reliability;
Analysis of Activity Parameters of CNC Machine Tools Failures Based on Gutenberg–Richter Curve
Jie Yu, Zhiwei Zhu, Tiebin Wang, Yue Yao, Jiexiang Ding
Abstract: Gutenberg–Richter (G-R) scaling relations are commonly used on seism prediction. The variance of b-values can reflect the seism active degree of the area. B value in frequent failure time is lower than in stable failure time. We use the curve to calculate the values of parameters a and b in the Gutenberg–Richter (G-R) relation, draw a graph of the b-value and the ratio of the number of failures over time, and find that the trend is reversed, which prove that the b-value can reflect the ratio of the number of failures. Draw the trend curve of a-value and lgN. By comparing and finding the same trend, it is proved that the a-value can reflect the overall level of failure data. The relationship between a and b-value is analyzed and the influencing factors on activity parameters are discussed.
Keywords: CNC machine tool, Gutenberg–Richter (G-R) curve, a-value, b-value, Gutenberg–Richter (G-R) scaling relation;
Fault Status Information Monitoring Technology for Large Complex Electromechanical System
Baoli Wei, Hongtao Jiao
Abstract: In order to improve the accuracy of fault state monitoring of electromechanical system, a fault state informatization monitoring technology for large complex electromechanical system is proposed. Based on the standard PD (Partial Discharge) signal expression derived from the traditional communication theory, the characteristic value of the fault signal is calculated, and the feature of the fault state signal is extracted by using the functions of the time and frequency of the fault state of the electromechanical system. Experimental results show that compared with the information monitoring technology based on support vector machine, the proposed fault monitoring technology has a higher monitoring accuracy.
Keywords: complex electromechanical; system fault state; informatization; monitoring technology;
Method of Power Performance Fault Alarm of Hybrid Electric Vehicle Based on Hydraulic Technology
Wenjuan Liu
Abstract: Due to the lack of precision in the modeling of the vehicle power system, the fault diagnosis and alarm accuracy of the current hybrid vehicle dynamic performance fault alarm method is reduced. Therefore, a hybrid vehicle dynamic performance fault alarm method based on hydraulic technology is designed. The power system model of hybrid electric vehicle is built by hydraulic technology, which is the data base of fault diagnosis. The method of self-diagnosis and the knowledge base of fault diagnosis are used to realize the fault diagnosis of vehicle power system. The interface between mobile network and on-board information is selected to realize vehicle fault alarm by setting alarm information content. The fault diagnosis accuracy of this method is always between 88.5% and 94.5%, the fault diagnosis time is less than 0.5 s, and the highest effective failure alarm rate is 99.8%. The experimental results show that the research method has the advantages of high accuracy, short diagnosis time, high effective alarm rate, low cost, superior economic performance and good application effect.
Keywords: hydraulic technology; hybrid vehicle; fault diagnosis; fault early warning; power system modeling; mobile network;
Wenbo Yang, Gang Li
Abstract: Due to the particularity of the aluminum alloy equipment material, it is extremely susceptible to mold corrosion and corrosion in the case of external environmental pollution, affecting the performance of the equipment. Taking the aluminum alloy equipment contaminated by mold as the research object, the control model of mold contamination was constructed under different ultraviolet irradiation intensity. This includes separating and purifying from corrosion samples of aluminum alloy, and obtaining test culture strains, measuring the change of pH value in the corrosion medium, and then studying the growth characteristics of Aspergillus niger in pure Chagas medium. Through electrochemical testing and surface morphology analysis, the growth and corrosion behavior of mold on the surface of aluminum alloy were studied. It is essential to change the irradiation intensity and irradiation time of ultraviolet ray to study its control effect on aluminum alloy mold corrosion. The experimental results show that the sterilization effect is the most effective and economical when the UV intensity is 84000 μW/cm2 and the irradiation time is 30 min.
Keywords:Ultraviolet radiation intensity; aluminum alloy equipment; mold contamination; control model; corrosion behavior;
Fault Tolerant Control Method of Power System of Tram Based on PLC
Zhenzhen You
Abstract: Due to the large fault classification granularity of tram power system, there is still a problem that the gain coefficient is not reasonable in different control links, so a fault-tolerant control method of tram power system based on PLC is designed. First, the fault classification of the tram power system is carried out, then the fault diagnosis of the tram power system is carried out. Finally, the fault-tolerant control of the tram power system is carried out through the angle fault-tolerant control unit, PID control algorithm model and brake pull fault-tolerant control unit, as to complete the fault-tolerant control of the tram power system based on PLC. The experimental results show that the reasonable value of proportional gain coefficient, integral gain coefficient and differential gain coefficient are 30.00, 15.00 and 29.98 respectively.
Keywords:PLC; tram; Power system; Fault-tolerant control; Fault diagnosis;
Jia Zhang
Abstract: In order to solve the problem that the accuracy of the controller of the traditional mechanical control system is not high and the efficiency of the control system is too low, a mechanical control system based on maximum power point tracking is designed. Through the controller platform, the embedded microprocessor with arm architecture is used to design the basic peripheral circuit, and to improve the control accuracy of the controller, and to complete the hardware design of the system. According to the characteristics of the compression efficiency of the liquid pump, the energy storage device is modeled, the maximum power point tracking algorithm is used to control the speed of the motor, and the software design of the system is completed. Regarding the hardware and software design of the system, the mechanical and electrical control system design of the mixed liquid gas pressure energy storage device is realized. The experimental results show that the design system is basically consistent with the standard control value, the system efficiency is the largest, and the mechanical and electrical control accuracy of the mixed oil and gas energy storage is improved, and the active power can reach a stable state.
Keywords:Maximum power point tracking; Mixed liquid gas pressure energy storage machine; Control system; Efficiency value;
Optimal Quay Crane Assignment and Scheduling in Port’s Container Terminals
Abbas Al-Refaie, Hala Abedalqader.
Abstract: Effective scheduling of quay cranes can increase throughput, and lead to higher revenues of container terminals. This research, therefore, proposes an optimization model to deal with quay crane assignment and scheduling problem (QCASP) considering multiple objective functions. The first objective minimizes the handling makespan in the terminal by sequencing the work of quay cranes on vessels' bays, while the second objective aims to maximize the number of containers being handled by each quay crane (QC) for all QCs in the container port to make sure that all QCs are utilized during the handling process. Finally, the third objective seeks to maximize satisfaction levels on handling completion times. The model takes into consideration the non-violence of non-crossing constraints and task completion without preemption constraints. Illustrations of the developed model were provided. The results showed that the proposed optimization model is found effective in optimizing terminal performance by optimizing the three stated objective functions concurrently. In practice, solving the QCASP helps in enhancing utilization of QCs, shortening service period at the terminal, and increasing the throughput at the terminal. In conclusion, the proposed optimization model can benefit planning engineers in determining optimal quay crane assignment and scheduling. Future research will focus on integrating berth allocation problem with QCASP.
Keywords: Optimization, Quay cranes, Scheduling and Assignment;
Subham Agarwal, Santonab Chakraborty, Kanika Prasad, Shankar Chakraborty
Abstract: In the present day, automated industries, such as arc welding robots have found immense applications in manufacturing of steel furniture, automobile components, agricultural machineries etc. Selection of the most appropriate robot for a specific welding application can be treated as a multi-criteria decision making problem where the best alternative needs to be identified with respect to a set of conflicting evaluation criteria. In this paper, rough numbers are integrated with multi-attributive border approximation area comparison (MABAC) approach for solving an arc welding robot selection problem. The opinions of five decision makers are aggregated together using rough numbers to avoid subjectivity in the decision making process, while MABAC method is employed to rank the candidate alternatives and choose the best robot for the given welding application. The criteria weights are determined using rough entropy method, which reveals that welding performance and payload are the two most important arc welding robot selection criteria, followed by cost of the robot. The application of rough-MABAC method identifies robot A6 as the most suitable choice and robot A2 as the least preferred option.
Keywords:Arc welding robot; MABAC method; Rank; Rough set theory; Selection;
Lead-Free Solder Reliability Modeling Using Adaptive Neuro-Fuzzy Inference System (ANFIS)
Azmi Alazzam, Tariq Tashtoush
Abstract: Lead-free solder is a new material that has been utilized in manufacturing electronic components and packages; therefore, the material behavior had not been analyzed completely. This paper summarizes our effort to model the change in lead-free solder hardness behavior with respect to aging time and temperature as a measure of the components’ reliability. ANFIS is a modeling technique that had been used in analyzing the current trend and predicting future progression. The ANFIS model was developed based on the BPN-ANN structure with two inputs and one output using Matlab®. The developed model was compared to different regression models that are being used frequently in the literature. The well-trained ANFIS model gave very accurate results for predicting the hardness (output) with a small Root Mean Square Error (RMSE) compared to the Minitab® regression models. ANFIS is one of the best techniques in modeling non-linear data, and it can give better and more accurate data representation and future prediction.
Keywords:Fuzzy Logic, Neural Network, Behavior Modeling, Lead-Free Solder, Aging, Reliability, Electronic packages, Matlab, Minitab;
Ahmad K. AL-Migdady, Ali M. Jawarneh, Amer Khalil Ababneh, Hussein N. Dalgamoni
Abstract: In this study, numerical simulations were carried out to analyze the cooling behavior of PCM-based heat sinks integrated with Aluminum foam. The performance of the PCM based heat sink is investigated under various operating parameters including: metal foam porosity (ε =100%, 97% and 90%), Two different PCMs (RT35HC and RT44HC) and three different values of convective heat transfer coefficient (10, 20, 30 W/m2.K) while keeping the heat flux input constant at 3200 W/m2. Better cooling characteristics were achieved in the heat sink filled with RT35HC when compared to RT44HC based heat sink. The Aluminum foam insertion further decreased the base temperature by almost (6 and 5)°C for the (ε =97% and 90%) respectively when compared to the no-metal foam case (ε =100%). likewise, in the RT44HC based heat sink, a further decrease in the base temperature by almost (5 and 4)°C was reported for the (ε =97% and 90%) cases respectively when compared to the no-metal foam case (ε =100%). The increase in the convective heat transfer coefficient resulted in longer time needed for PCM melting.
Keywords: Aluminum-foam, heat sink, Phase change material “PCM”, Electronic cooling;
Farooq Sk, D. Vinay Kumar
Abstract: The present work aimed at optimizing the performance and emission characteristics of a Port Fuel Injection (PFI) SI engine fueled with Gasoline-Ethanol-Methanol (GEM) blends using Response Surface Methodology (RSM). Test fuels used in the study are pure gasoline (E0), E10, E10 equivalent iso-stoichiometric GEM blend (E10_Eq), E20, E20 equivalent iso-stoichiometric GEM blend (E20_Eq). Formulated E10 and E20 equivalent blends have identical air-fuel ratios, lower heating values, density, and octane number as target binary blends (E10, E20). The test engine was operated with different fuel blends by varying the engine speed from 1700 to 3300 rpm at a constant engine load of 5 kg. For optimization of the engine, speed and fuel blends were considered as input parameters and brake thermal efficiency (B_The), brake specific fuel consumption (BSFC) and, nitrogen oxide (NOx) emissions as responses. Optimization was carried out using the desirability approach with a target of maximizing the B_The and minimizing the BSFC and NOx. From the results, it was observed that the E10_Eq GEM blend operation of the test engine has optimized values of B_The, BSFC, and NOx emissions with values of 33.17%, 251 g/kW-hr, and 1389.8 ppm respectively at an engine speed of 2416 rpm. A composite desirability value of 0.64 obtained from the regression model shows that RSM can be conveniently employed to determine the significant factors that could impact engine performance and emissions;
Keywords: GEM blends, Response surface methodology, Analysis of variance, Equivalent blends;
Design and Development of a promising Biochar-based Copper Catalyst
Mohammad Hossein Nargesi, Reza Yeganeh, Fatemeh Valizadeh kakhkib Maryam Hajjami
Abstract: As about 70 percent of the air pollution comes from vehicles, automotive companies have always been seeking novel catalytic converters to reduce engine emissions. However, so far, a comprehensive research on the impact of copper catalytic converters on biochar has not been conducted. This research aims to study the effect of biochar-based catalytic converter on the amount of exhaust emissions in an XU7 engine. Two thicknesses of the biochar-based catalysts, 7 and 14 cm and Cu (No3)2 in two densities of 1 and 2 mmol were applied for the experiments. Five types of contaminants (i.e., CO, CO2, HC, O2 and NOx) were measured for the evaluation of exhaust emissions. In this study, the XU7 engine, which was produced in 2011, was used to perform the tests. The results showed that the levels of exhaust gases from combustion of the XU7 engine were low and acceptable in all treatments in comparison to the environmental standard. In addition, the catalyst used in the XU7 engine had a significant impact on the absorption of exhaust gas from the engine, especially for CO and the level of its concentration was significantly different in comparison with a new catalyst, biochar-based catalysts and control and also, for HC the levels of concentration were shifted applying biochar-based catalysts comparing to the new catalyst and control. Based on the results, it was observed that applying the proposed approach can be an effective step in reducing greenhouse gas emissions from combustion and increasing the life span of engines.
Keywords: XU7 Engine; Biochar;Copper catalyst;NOx;Exhaust emissions;
Ehsan Abbasi Teshnizi, Mehdi Jahangiri, Akbar Alidadi Shamsabadi, Luis Martin Pomares, Ali Mostafaeipour, Mamdouh El Haj Assad
Abstract: Among various types of renewables, wind energy requires a less initial investment that is projected to decrease even more due to technology advancement, a higher number of turbines, and ease of restrictions. Unlike traditional power-plants, wind turbines have been developed in various dimensions, and minimal land is taken out of production, so they are recommended for small countries facing a lack of space. Given these facts, a potentio metric study of supplying the electricity of a residential house in 5 cities of Abu Samrah, Ar-Ruways, Doha, Duhan, and Musayid, Qatar, is performed using HOMER and meteorological 20-year-average data taken from the NASA website. The studied system is connected to the grid, and a techno-Econo-environmental study is conducted. The study results of the turbulence intensity (TI) parameter indicated the mechanical components of the wind turbine in the Doha station were under intermediate fatigue loads while these loads were lower in the remaining stations. According to the results, it is clear that Doha station, with a price per kWh of electricity generated, and a total net present cost (NPC) of $0.086 and $6349, respectively, produces the most cost-effective wind power electricity due to using BWC XL.1 horizontal axis wind turbine. The highest amount of CO2 emissions savings and most top production of CO2 are associated with Doha (-300 kg) and Abu Samrah (2844 kg) due to using EOLO and Turby wind turbines, respectively. Ar-Ruways generate the highest (8890 kWh/y) and lowest (658 kWh/y) amounts of wind power electricity and Abu Samrah stations which are due to utilizing Generic 10 kW and Turby wind turbines, respectively.
Keywords: Power curve; Hub height; Wind speed; National electricity grid; Weibull function;
Magnus Wind Turbine Effect Vertical Axis Using Rotating Cylinder Blades
Khalideh Al bkoor Alrawashdeh, Nabeel.S.Gharaibeh, Abdullah A. Alshorman, Mohamad H. Okour
Abstract: The aerodynamic characteristics of a Magnus wind turbine (MWT) with cylinder blades are evaluated by using numerical simulation COMSOL. Yaw and lifting systems are used to identify the features of the MWT to maximizing power output at minimum tresses, torque and fatigue. MWT is characterized by low efficiency of power production. Therefore, it is important to seek effective components to improve the power performance of MWT. The blades design in Yaw and lifting system are critical parameters that affect MWT performance. In this study, five suggestions were discussed to choose the best configurations of MWT in order to promote MWT application. Performance characteristics, such as stresses, Torque, deflection and fatigue with suggested configurations are analyzed and compared to identify the desirable components for this type of MWT. The results showed that the aerodynamic characteristics of MWT in this study will be presented as a significance guide for the initial research and preliminary design of MWT. Based on the suggested design configuration, the results showed that the Von Mises stresses are low at the bottom and high at the top, and the buckling is very high at the top but low at the bottom of the base while the maximum value of Findley’s fatigue is for the bottom as a result of axial stress. As for the designed shaft, the force increases when the stress increases accordingly, therefore, the deflection also increases. Moreover, the results showed more specified ranges of stresses distributions on blades and deflection ranges of decrease and increase that enable for better design, control and power utilization of turbine.
Keywords: Magnus effect, wind turbine, stress, deflection, torque, yaw system;
Mite Tomov, Bojan Prangoski, Pawel Karolczak
Abstract: This paper presents a research primarily aimed at determining the correlations between the primary profile, waviness, and roughness profiles during hard turning, using mathematical modeling of the primary profile (Pa), the roughness profile (Ra) and the waviness profile (Wa). For this purpose, we employed the Design of experiments (DOE) principles expressing the roughness parameters models as a nonlinear function shape of the first order of the input variables: cutting speed (v), feed (f), depth of cut (ap) and tool nose radius (rε). The models were done based on empirical data obtained by processing special rings made of stee lEN C55 (AISI 1055) with hardness of 53±1 HRC, using a CNC lathe. The obtained results are presented as mathematical models, but also as 3D diagrams which clearly show the change trends and their mutual relationships for the considered parameters.
Keywords: hard turning, surface roughness, primary profile, waviness profile, roughness profiles, mathematical modeling;
Data Envelopment Analysis in the Presence of Correlated Evaluation Variables
Mohammad Bastani, Saeedeh Ketabi, Reza Maddahi, Roya M.Ahari
Abstract: Data Envelopment Analysis (DEA) is a technique for evaluating homogeneous Decision-Making Units (DMUs) that consume similar inputs to produce similar outputs. An essential principle in this method is to identify inputs and outputs; the identified inputs (outputs) must be independent of each other. However, in the real world, there are situations where there is a correlation between two or more inputs (outputs), and then one of them should be considered in the performance evaluation. This issue can cause problems in practice. The main question, in this case, will be that" Which of these two or more correlated variables should be considered in evaluating DMUs?". In this paper, a method for determining an essential variable using a DEA model is presented. In this way, the basic models of DEA have been integrated with the 0-1 programming to achieve the above objective. The proposed method is then improved by using Centralized Data Envelopment Analysis (CDEA) model, followed by refining the performance evaluation variables. At last, the application of the proposed method has been verified for different examples. Results show that the proposed method selects the appropriate variable from among the correlated variables. Also, improving the method using a centralized approach leads to the selection of a variable that increases the total efficiency. The application and implementation of the proposed method is simple and does not have computational complexity. It also does not need experts’ judgment, so it is a cost-effective way.
Keywords: Centralized Data Envelopment Analysis, Correlated variables, Performance evaluation, Filtering variables;
Mohamed MAINE, Mohamed EL OUMAMI, Otmane BOUKSOUR, Boujemâa NASSIRI
Abstract: In this article, passive flow control around a generic car model has been investigated numerically. A deflector installed on the rear window of the Ahmed model at 25° was used to study the aerodynamic effect. The study involves the analysis of a set of eight two-level deflector-related factors with the aim of assessing their effects on aerodynamic drag. The assays were determined by establishing a Plackett-Burman screening plan and the results are studied by JMP Pro 14 software. It was observed that the factors (type of deflector, inlet velocity and length’s ratio) have a significant effect on reducing aerodynamic drag. The optimal test conditions proposed by the Plackett-Burman plan were investigated numerically and the value obtained was slightly higher than the value of the screening design. It was concluded that the model of Ahmed with optimal deflector gives the best drag reduction, compared to the model without deflector. Installing the optimal deflector on Ahmed’s body widens the wake area and eliminates chainstay vortex.
Keywords: Aerodynamic drag, Generic car, Ahmed model, Deflector, Plackett-Burman plan;
J. Pavalavana Pandian , M. Pugazhvadivu , B. Prabu, K. Velmurugan, V.S.K. Venkatachalapathy
Abstract: Diesel engines are the most ideal prime-movers for automobiles, railways, and marine transport to generate power. A hasty switch to alternative fuels is crucial to meet the diesel fuel demand as well as to safeguard the environment from the pollution caused by the diesel fuel combustion. In recent periods, biodiesel becomes an established possible substitute fuel for Compression Ignition (CI) engines as it offers numerous important advantages like bio-degradability and renewability. It also produces comparable engine performance and relatively lowers toxic emissions. A single cylinder, 4.4 kW rated power CI engine was operated with biodiesel with Pyrogallol (PY) stored at optimized storage conditions (B100 (PY)), biodiesel stored at 4.5 months at ambient condition (B100) and diesel fuel. The engine performance results indicate that the brake specific fuel consumption by B100 (PY) was lower with 9.62% than that of B100 and 15.09% higher than the base line diesel fuel. The thermal efficiency of the engine fuelled with B100 (PY) was comparable with diesel. The engine thermal efficiency with diesel and B100 (PY) is 31.79% and 29.53% respectively. Further, there was no significant changes in combustion characteristics, viz. heat release rate and gas pressure available in cylinder between B100 (PY) and diesel fuel. The Nitrogen Oxides (NOx) with B100 (PY) was 15.04% higher than diesel. This is because of 10 - 11% oxygen substance present in biodiesel. However, the NOx concentration by B100 (PY) was 8.43% lower than B100. Similarly, the smoke density with B100 (PY) was 9.83% and 25.72% lower than B100 and diesel fuel respectively. The engine performance results thus showed that waste frying oil (WFO) biodiesel has to be stored under optimum conditions to obtain equivalent engine performance and lower emissions.
Keywords: Biodiesel, waste frying oil, antioxidant, pyrogallol, storage stability, diesel engine;
N.Kapilan
Abstract: Biodiesel is considered an immediate substitute for the fossil diesel as the fuel properties, such as calorific value, density, ash content and acid value are comparable to the diesel. In India, pongamia oil has considerable potential for the biodiesel production. The pongamia oil biodiesel has lower volatility and slightly higher viscosity than the diesel. Hence the pongamia oil biodiesel fuelled diesel engine results in lower thermal efficiency as compared to the diesel. The carbon nanotubes (CNTs) were used in this work as additive to the pongamia oil biodiesel, to enhance the atomization and to reduce the ignition delay of the pongamia oil biodiesel. The CNTs were added to the pongamia oil biodiesel with different dosages and subjected to ultrasonication for 60 min, to prepare homogenous mixture. The engine tests were conducted on a single cylinder diesel engine without making any modifications in the fuel injection system. The addition of CNTs to the pongamia oil biodiesel resulted in higher brake thermal efficiency at higher loads between 75 to 100 % of the full load. From the engine tests, it was observed that the CNTs improves the engine thermal efficiency and reduces the CO, HC and smoke emissions of the diesel engine depends upon the CNT dosage. This is due to shorten ignition delay caused by the CNTs which improves the combustion of the pongamia oil biodiesel. The optimum CNT dosage of 50 mg/l results in 4% increase in thermal efficiency and reduces the CO, HC and smoke emissions by 20.33, 25 and 12.5% respectively at full load;
Keywords: pongamia oil, biodiesel, alternative fuel, carbon nanotubes, engine tests;
Effect of Gable Roof Angle on Natural Ventilation for an Isolated Building
Lip Kean Moey, Man Fai Kong, Vin Cent Tai, Tze Fong Go, Nor Mariah Adam
Abstract: Airflow characteristics around and within an isolated gable roof building were investigated using computational fluid dynamic with steady RANS equations. This study focuses on the following parameters: streamline of normalized velocity, pressure coefficient, and normalized turbulent kinetic energy. Three different roof pitches of the gable roof namely 15º, 25º, and 35º were considered. The streamline shows that an increase in roof pitch results in a corresponding increase of velocity at the window openings. Meanwhile, the streamline velocity at the roof opening varies across different roof angles. On the other hand, the pressure coefficient at the windward side and interior of the building decreases as the roof pitch becomes steeper. Variation in the flow fields of 25º and 35º roof pitch with window and roof opening, is relatively more apparent as compared to that of a 15º and 25º roof pitch. The turbulent kinetic energy at the leeward side of the building also becomes larger with the increase in roof pitch. Therefore, airflow behavior and characteristics are significantly dependent on the roof pitch which shows good agreement with the literatures. A higher roof pitch of gable roof building is, therefore, preferred for better ventilation rate.
Keywords: Natural Ventilation, Gable Roof, CFD, Roof Pitch, Steady RANS, Ventilation Rate;
Fadi Alfaqs
Abstract: Composite laminated structures have attracted much attention in recent years due to their wide range of mechanical properties and applications. However, this study presents an investigation of temperature impact as well as fiber orientation effect on mid-plane transverse deflection and interlaminar shear stress as the latter plays a crucial role in the layers’ delamination in eight-layer laminated simply supported Graphite/Epoxy FRP composite beam. The beam considered is subjected to dynamic force of magnitude 1000 N concentrated in the middle as frequency varies 5-50 Hz using 3-D finite element modeling where different fiber orientations ([0o]8, [0o/15o]s, [0o/30o]s, [0o/45o]s, [0o/60o]s, [0o/75o]s, and [0o/90o]s) are considered for temperature 22, 40, and 60oC. Furthermore, modal analyses are carried out for all fiber orientations and temperatures considered. Results obtained via this study show that natural frequencies’ values drop narrowly when the temperature applied on the structure rises. Moreover, dynamic mid-plane transverse and interfacial shear stress increases when increasing temperature. It should be said that comparing fiber orientations considered for every single temperature across the frequency range, fiber orientation scheme [0o]8 recorded minimum transverse deflection and maximum shear stress.
Keywords: Laminated Beam; Dynamic; Modal, interlaminar Shear stress; Finite element;
Mohamad I. Al-Widyan, Borhan A. Albiss, Mohammad S. Ali
Abstract: This work sought to investigate experimentally the applicability of an alkaline nitrate (NaNO3 and KNO3)-coated TiO2 working electrode in a dye-sensitize solar cell (DSSC) in enhancing the cell’s performance. A simple dipping method was used to modify the surfaces of TiO2 films with nitrate aqueous solutions with concentrations of 0.01M, 0.05M and 0.1M. Using standard SEM, XRD and UV-Vis apparatus, the modified cell performance was compared with an equivalent bare-TiO2 surface in terms of performance at two temperature levels. It was found that with higher alkaline concentrations, the electrode surface was covered with smaller, denser and nicely oriented nitrate nanoparticles, as well as superior optical performance and a quite successful incorporation of the alkaline nitrates with TiO2 paste. The modified DSSC consistently showed higher power conversion efficiency. Specifically, findings indicate that the power conversion efficiency of the modified cell increased by up to 200% relative to its unmodified one. In addition, it was found that the conversion efficiency using NaNO3–TiO2/ITO layer was better compared to the KNO3–TiO2/ITO layer at all concentrations and temperature levels considered. The highest power conversion efficiency was recorded in the DSSC with NaNO3 (0.1)–TiO2/ITO layer at 1.029% and 0.84% at 13 oC and 40 oC, respectively. Moreover, the findings reaffirmed the positive effect of lower temperature on cell performance.
Keywords: Dye-sensitized solar cells, Cell performance, Cell temperature, Electrode modification, Alkaline nitrates, TiO2 nanoparticles;
G.V.S.S.Sharma, P. Srinivasa Rao, B. Surendra Babu
Abstract: Quality of the product is a very important factor to any organization on which the future of the company depends. There are many tools available to check and control the quality of the product, and among them is the process capability study which is highly important. This work is an attempt towards applying the concepts of process capability principles pertaining to discrete manufacturing into the scenario of continuous process oriented industries. In this work, the process capability study is carried out in a sugar processing industry. Data pertaining to Critical-To-Quality parameters of sugar have been collected for several sugar samples. The reasons for the variability are identified and the necessary and corrective actions are suggested to overcome the variations in the sugar manufacturing process. A significant improvement is registered in the process capability indexes of CP and CPK for the identified Critical-To-Quality (CTQ) characteristics of sugar turbidity and minimum aperture. An increase of 7 folds is observed for the CPM value for the CTQ characteristic of minimum aperture. Thus, the process capability indexes are calculated and the capability of the process is determined based on their values.
Keywords: Quality Assurance; Process capability; Sugar processing; Statistical Process Control; ANOVA analysis; Critical-To-Quality (CTQ) characteristic;
Aluminium Alloys Nanostructures Produced by Accumulative Roll Bonding (ARB)
Yazan M. Almaetah, khaleel N. Abushgair, Mohammad A. Hamdan
Abstract: The accumulative roll-bonding process (ARB) is one of the severe plastic deformation methods. It aims at producing nano/ultra-fine-grained materials along with enhancements in the mechanical properties. In this work, ARB was performed on commercially cheap and available aluminium alloys in Jordan`s local market; AL-2024-O and AL-1100-Oalloys. Four bonding cycles were applied to promote grain refinement at room temperature with no pre/post heat treatment. In ARB processes, the thickness is reduced by 50% in each pass. A new stacking technique has been performed at the alternate layers depending on the friction of its scratched edges. After the production of samples and the investigation of mechanical properties through micro hardness test, tensile test was accomplished at room temperature after each cycle with the aim of determining whether ARB increases the mechanical properties of both aluminium alloys besides identifying the instance were material experiences high ultimate tensile strength. Information about the texture, microstructure and average crystalline size of the samples was obtained using SEM and XRD. The hardness test shows improvements for AL-2024-O/1100-O for each cycle and reported 125 HV and 80 HV respectively after four rolling cycles. The highest UTS was recorded for AL-2024-O and 1100-O on the 4th pass and reported 370 MPa and 170MPa respectively. It was also found out that the percentage elongation decreased due to a decrease in ductility after undergoing the ARB process. Moreover, after four rolling cycles, the average grain size for AL-2024/1100 decreased to 39.6 nm and 59.9 nm respectively.
Keywords: Severe plastic deformations, Accumulative roll bonding, Nanostructures, Aluminium alloys;
Simulation of Trajectory Tracking and Motion Coordination for Heterogeneous Multi-Robots System
Samer Mutawe, Mohammad Hayajneh, Suleiman BaniHani, Mohammad Al Qaderi
Abstract: The paper addresses developing a team of aerial and ground robots to accomplish multi-robot system navigation task in an accessible way. The motions of two different robotic structures, namely quadcopter, and differential drive mobile robots are simulated and controlled. Two-level controller has been adopted for the multi-robot system. A low-level controller is utilized for each robotic platform to insure its motion stability and robustness. Then, a formulation of high-level tracking controller is presented to allow each robot to avoid obstacles in a dynamic environment and to organize its motion with other flying/ground robots. The performance of the proposed system is demonstrated in a simulation environment. A modeling platform is adopted to construct the simulation environment, which allows the user to easily adjust the models and controller parameters as well as to implement different control algorithms. In addition, the simulation environment helps in analyzing the obtained results and performing several tasks in different conditions. The real-time motion of multi-robot system is monitored in the created environment that provides three-dimensional graphical displays of the robotic platforms. Simulation results show that the aerial and ground robots produced trajectories individually to reach different targets. Meanwhile, each robot in the system was able to navigate among obstacles without colliding with other agents in the network.
Keywords: Ground robot, Multi-robots, Path planning, Quadcopter, Trajectory tracking;
Control of Wake Behind an Unconfined Wedge Structure by Magnetohydrodynamics
JShailendra Rana, Hari B. Dura, Rajendra Shrestha
Abstract: The laminar, viscous and incompressible flow of an electrically conducting fluid across an unconfined wedge structure in the presence of a transverse magnetic field has been studied. Two-dimensional numerical simulations have been performed for Reynolds number (Re) = 1-150 and Hartmann number (Ha) = 0-10 for a fixed blockage ratio (β) = d/W = 1/30. The magnetic induction method in magnetohydrodynamics module built in ANSYS FLUENT solver has been employed to compute the flow fields. Results show that the vortex shedding can be completely eliminated if the applied magnetic field is strong enough. In the steady flow regime, it has been found that the recirculation length reduces with the increase in Ha. A minimal reduction in the drag coefficient is observed with the increase in Ha as long as unsteady flow is maintained (Ha < 7.3). However, the drag coefficient has a tendency to significantly increase with the increase in Ha for steady flow. Similarly, the lift amplitude decreases with the increase in Ha indicating a diminishing effect on the strength of vortices. A critical Hartmann number (Hacr) of 7.3 has been found for Re = 100 at which complete suppression of vortex shedding is observed.
Keywords: Magnetohydrodynamics, active vortex suppression, Strouhal number, magnetic Reynolds number, Hartmann number;
Rashid Ali , Anshumaan Singh
Abstract: Effects of inertia and buoyancy forces are numerically investigated on fluid dynamics and heat transfer characteristics for the flow past a heated square cylinder in an unconfined flow regime. Non-dimensional number in the study chosen are Re = 1 - 45, Ri = 0 - 1.50, α = 0o– 90o. The orientation of the cylinder and the Prandtl number are kept fixed as ϕ = 0oand Pr = 100. Numerical experiments in generalized body-fitted coordinates subject to Boussinesq approximation were conducted in the form of solution of continuity, momentum and energy equations. The momentum and energy equations are discretized using finite difference method. The equations are solved by using SMAC type implicit pressure correction scheme. The flow is noticed steady for 1 ≤ Re ≤ 30 and 0 ≤ Ri ≤ 0.50 at α = 0o, 1 ≤ Re ≤ 20 and 0 ≤ Ri ≤ 0.50at α = 45o, 1 ≤ Re ≤ 10 and 1.0 ≤ Ri ≤ 1.50 at α = 90o. Onset of vortex-shedding is observed initially at Re = 30, α = 45o, 0 ≤ Ri ≤ 0.50, the flow becomes unsteady and periodic flow. At small magnitudes of Reynolds number, the wake on downstream side of cylinder is found thin, and it becomes wider at large magnitudes of Reynolds number. It is noticed that the width of the wake reduces in size with increasing Richardson number. Maximum mean lift coefficient is found to occur at Re = 20, Ri = 1.5 and α = 90o, and maximum mean drag coefficient is noted at Re = 1 for the chosen range of Richardson number and free-stream orientations. For the whole range of Reynolds and Richardson numbers, the front face(s) of the cylinder had more crowding of isotherms in comparison with other faces of the cylinder. The front face(s) of the cylinder have high rate of heat transfer as compared to other cylinder faces. Heat transfer rate from the cylinder is enhanced either with increase in Richardson number or Reynolds number.
Keywords: Mixed convection, streamline and isotherms patterns, contours of vorticity, Nusselt number, rate of heat transfer;
Investigation on the Performance of Order Release Methods in a Flow Shop with Bottlenecks
Aruna Prabhu, Raghunandana K, Yogesh Pai P
Abstract: The workload control (WLC) is a popular concept in manufacturing planning and control, which plays a significant role in enhancing the efficiency of manufacturing firms that have uncertainty in meeting customer orders. Owing to changes in several set of factors, such as processing time variations, fluctuation in orders, and rise in quality issues etc., would disrupt production schedules and adversely affect the shop performance. Improvements are certainly possible by integrating WLC policies in distinct stages of production that in turn help to keep a steady workflow and balanced shop floor activities. In this study, we have considered the production of a part of a windmill that poses difficulties in production due to changes in processing times. A production shop simulation model was developed by considering real-time data. The model is simulated to analyze the performance under different order release methods at process time changes. In addition, we consider the influence of downtime and capacity cushion at bottleneck station. The objective of this research is to investigate the influence of the processing time variation, downtime, and capacity cushion on the performance of the shop floor and to evaluate the best release method suitable in different situations.
Keywords: Workload control, Order release methods, Work in process, Simulation;
Nabeel Alshabatat, Ahmad Abouel-Kasem
Abstract: This paper aims to investigate the effects of sulfur addition on enhancing the mechanical properties of Nitrile Butadiene Rubber (NBR) composites. The composites were prepared with the assistance of internal mixer and two-roll mill, and then the speciemns were vulcanized by electrically heated press. The NBR composites were prepared with different sulfur contents (2, 3, 4, 5, and 7 phr). The tensile strength, hardness, compression set, tear strength, and swelling ratio were investigated. The experimental results showed that the addition of sulfur to NBR composites improved their mechanical properties. The unaged NBR composite containing 7 phr of sulfur gives the best 20% modulus (650% improvement), and shore A hardness (27.4% improvement). However, the unaged NBR composites containing 4 phr of sulfur gives the minimum compression set (i.e., 3.2%). Also, adding small amount of sulfur (less than 4 phr) increases the tear strength. The unaged NBR composite containing 2 phr of sulfur gives the best tear strength (106% improvement). The swelling ratio decreases significantly with adding sulfur contents. The unaged NBR composites containing more than or equal to 3 phr of sulfur give 0% swelling. Also, the effects of different aging conditions were investigated. The results showed that NBR composites which were aged in ozone and air degraded more seriously than those aged in oil.
Keywords: Nitrile Butadiene Rubber; sulfur content; rubber aging; mechanical properties;
Yuan-Shyi Peter Chiu, Chia-Ming Lai, Tiffany Chiu, Chung-Li Chou
Abstract: Transnational firms operate in turbulent and competitive marketplaces. They continually find ways to optimize their internal supply chains to guarantee that firms achieve operating goals of high quality, quick response time, smooth fabrication schedules, and timely deliveries under the reality of limited capacity and unreliable machines/processes. This study considers a vendor–buyer integrated batch-fabrication problem with outsourcing, rework, machine failures, and multiple deliveries to facilitate better decision making and assist enterprises in increasing their competitive advantages. We assume that a portion of a batch is outsourced in order to reduce manufacturing uptime, and in-house production experiences undesirable situations, such as machine failures and nonconforming stock making. Corrective action on failures and repair tasks of the nonconforming are undertaken in each cycle as they occur. The finished stocks are then shipped under the multiple-deliveries plan. We build a model to explicitly depict the problem and determine the problem’s cost function through formulations and derivations. The convexity of cost function and the optimal uptime are obtained via differential calculus and a proposed specific algorithm. Lastly, we offer a numerical example to show our proposed model makes diverse crucial system information, such as the individual and joint impact of outsourcing, rework, random failures, as well as the frequency of delivery on different features and the optimal uptime of the problem, easily accessible, to assist enterprises in strategic planning, management, and decision making in their practical intra-supply-chain environments.
Keywords: Vendor-buyer integrated system, Hybrid batch fabrication, Machine failures, Rework, Multi-delivery;
Sachin G Ghalme
Abstract: The generation of lignocellulosic agriculture waste and the residue is unavoidable, and disposal of the same with burning or burying creates environmental issues. In recent years the scientific community is continuously looking for sustainable development using natural resources for development. Rice husk (RH) and straw (RS) are already proposed as natural fiber reinforcing materials for natural fiber reinforced polymer composite (NFRPC). In this article, an attempt has been made to obtain the optimized proportion of rice husk and straw reinforcement in bio epoxy resin for the development of rice husk and straw fiber-reinforced hybrid composite with improved mechanical properties. The grey relational analysis (GRA) methodology is implemented to obtain the optimized proportion of RH and RS for maximization of tensile and flexural strength of polymer composite simultaneously. The experimental and grey relational analysis result presents the addition of 05 and 08 wt% of RS and RH fiber respectively in bio epoxy resin presents rice straw and husk reinforced polymer composite with improved tensile and flexural strength simultaneously.
Keywords: Natural fiber reinforced polymer composite (NFRPC), rice husk (RH), rice straw (RS), mechanical properties, grey relational analysis (GRA);
Junjie Gong, Wei Wei, Sixu Peng, Kechen Zhang
Abstract: Most of the parallel mechanisms (PM) with low coupling degree cannot directly obtain the analytical expression of the positive position solution of the PM, which makes it difficult to carry out the follow-up research on the kinematic accuracy analysis and trajectory planning of the PM. Based on the topological structure theory, this paper analyzes the position and orientation characteristic(POC), DOF and coupling degree of 2PPa-PSS PM. Afterward, the kinematic mathematical model of 2PPa-PSS PM is established based on the order single open chain of kinematic modeling principle. The moving platform of the mechanism is set as an equilateral triangle, and the intermediate variables are solved by combining the constraints of the two chains. The positive position solution of the PM in analytical form is obtained. The correctness of the kinematic model of the mechanism is verified by numerical calculation. Then, according to the positive position solution analytical expression, we can work out the complete workspace of the PM, and the significant influence of the driving increment on the attitude change of the moving platform is analyzed by using the analysis method based on the orthogonal test. According to the results of orthogonal experiment, the best driving range of the mechanism is obtained.
Keywords: Positive position solution; Parallel mechanism; Coupling degree; Workspace; Orthogonal test;
Mostafizur Rahman, Md. Arafat Rahman
Abstract: To improve comfort, a quasi-zero stiffness (QZS) drivers’ seat suspension system is designed and fabricated based on potential energy method. At first, the mathematical model for the seat suspension is established. Thereafter, a model of seat suspension system with natural frequency of 2.45 Hz is fabricated to check validity of this method. A negative stiffness spring (NSS) is used as added system to reduce the natural frequency to 1.78 Hz. In addition, double NSS is added to suspension system to obtain QZS and natural frequency observed to near about 0.84 Hz. Hence, vibration magnitude of seat suspension is reduced to 27.3% in case of single NSS and 65.7% for double NSS compared with suspension system without NSS. Compared with the original seat suspension system, the new suspension system with NSS has better vibration isolation characteristics and can electively improve drivers’ ride comfort.
Keywords: Vibration; Natural frequency; Transmissibility; Suspension system; Potential energy; Quasi-zero stiffness; Stability;
Amine Hamdi, Sidi Mohammed Merghache
Abstract: In automotive industries, the belt grinding (BG) is a mechanical manufacturing process by removing material using a tool called an abrasive belt. This technique enables high surface quality and reproducibility of high-precision mechanical parts to be achieved. The main objective of this paper is to provide a detailed account of the effect of superfinishing on the surface texture of 16MC5 casehardened steel by the belt grinding process under the alumina abrasive grains (Al2O3) with average sizes (60, 40, 30, 20 and 9 μm), respectively. The surface quality was characterized by one surface roughness parameter (Ra) and three parameters of the Abbott-Firestone curve (Rpk, Rk and Rvk) in order to determine the relationship between the grains size reduction and the surface texture. As all mechanical machining processes with undefined tool geometry (e.g. grinding, polishing, lapping,...etc.), experimental results obtained during measurements suggest a clear relationship between the reduction in abrasive grains size and the surface texture. The minimum quantity lubrication (MQL) also decreases the surface roughness; the lubrication addition helps to achieve better surface quality than the dry belt grinding.
Keywords: Abrasive grains, Belt grinding, Superfinishing, Surface texture;
R.V.S.Subrahmanyam, Koona Ramji, Pujari Srinivasa Rao, ChundruVenkata Rao
Abstract: The main aim of this study is to evaluate the influence of particle size variations on electric discharge machining (EDM) electrodes made with a combination of Tungsten carbide (WC) and Copper (Cu) powders using the powder metallurgy (P/M) method. The electrodes are in cylindrical shape of 15 mm diameter and are made with following sizes i.e., Nano Particles (NP), a mix of Nano and Micron Particles (NMP) and Micron Particles (MP). Electrodes, thus made in combinations were used to study the performance during surface modification of Inconel 718 alloy using EDM. The electrodes were made with wt% 40, 50& 60 of WC and the rest is Cu, whereas the compaction ranges 200-400Mpa. Among the unconventional machining processes, EDM is the most preferred surface modification process to machine very hard materials like Inconel 718 alloy. Machining was conducted by varying parameters viz., pulse on time, polarity, peak current, %WC in tool composition, Particle size, and compaction pressure. The performance indicators in the present investigation are material removal rate (MRR) and tool wear rate (TWR). The results were analyzed using MINITAB 14 software, and it was noted that the improvement in MRR was due to the influence of particle size and peak current. A highest MRR of 9.90 mg/min was attained with NP electrode and a peak current of 13A. The highest TWR of 20.70 mg/min was also observed at the machining condition where highest MRR was observed. The results of the MRR and TWR values show the significant influence of all the six process variables on EDM process.
Keywords: EDM, WC- Cu, P/M compact sintered electrode, MRR, TWR, Inconel 718;
Ala Hijazi
Abstract: The two-dimensional digital image correlation (2D-DIC) technique is used for making full-field in-plane deformation/strain measurements on planar surfaces. One of the basic requirements for making measurements using 2D-DIC is to observe the target surface perpendicularly by the camera. Ensuring camera perpendicularity before starting to make measurements using 2D-DIC is important because errors will be induced in the measured displacements/strains if the camera is not oriented properly. During the initial setting of an experimental setup, small camera misalignment angles of one or two degrees can easily go undetected. This paper reports a simple and reliable approach for verifying the camera perpendicularity in 2D-DIC experiments, and for measuring the tilt angle(s) if the camera is not perpendicular to the surface. The approach uses in-plane rigid-body-translation where the strain error(s) obtained from DIC measurements are used to calculate the tilt angle(s). The translation can be either parallel to the target plane (done by moving the target) or parallel to the camera plane (done by moving the camera) where a different set of equations is used for calculating the tilt angles in each scenario. A translation of a known magnitude in any in-plane direction (parallel to the x or y axes of the image, or at any angle in between) is all what is required to calculate the tilt angle(s). The approach is also capable to determine the tilt angles if the target is tilted about any of the two in-plane axes (x or y) or about the two axes simultaneously. Several rigid-body-translation experiments are performed under different conditions to evaluate the validity and accuracy of this approach at tilt angles between 1° and 4°. The results show that tilt angles as small as 1° can be calculated accurately, and that rigid-body-translation as small as 2% of the field-of-view width can be used for making measurements with good accurac.
Keywords: Digital image correlation; 2D-DIC; normal strain error; shear strain error; strain bias; camera non-perpendicularity; camera misalignment; tilt angle; rigid-body-translation;
A Machine Learning Approach for Fire-Fighting Detection in the Power Industry
Firas Basim Ismail, Ammar Al-Bazi, Rami Hikmat Al-Hadeethi, Mathew Victor
Abstract: Coal kept in the coal storage yard spontaneously catches on fire, which results in wastage and can even cause a massive fire to break out. This phenomenon is known as the spontaneous combustion of coal. It is a complex process that has non-linear relationships between its causing variables. Preventive measures to prevent the fire from spreading to other coal piles in the vicinity have already been implemented. However, the predictive aspect before the fire occurs is of great necessity for the power generation sector. This research investigates various prediction models for spontaneous coal combustion, explicitly selecting input and output parameters to identify a proper clinker formation prediction model. Feed-Forward Neural Network (FFNN) is proposed as a proper prediction model. Two Hidden Layers (2HL) network is found to be the best with 5 minutes prediction capability. A sensitivity analysis study is also conducted to determine the influence of random input variables on their respective response variables.
Keywords: Spontaneous combustion of coal, Artificial Neural Network, Clinker Formation Prediction Models, Coal-fired power plant;
Kiran Aithal S, Ramesh Babu N, Manjunath HN, Chethan KS
Abstract: Centrifuge casting is a new technique wherein a mold assembly is made to rotate at a certain speed that will induce higher 'G' force to the molten metal.The existing higher rotational force creates a compositional gradient that segregate phases with different densities. In this work, an attempt has been made to develop Al alloy/ SiCP FGMs. It has been observed that due to the higher density of SiC compared to Aluminum, the bottom part of the casting is rich in SiC particles with good resistance to wear, and the top of the casting results in high toughness as it is more of Al alloy. In the present work FG Composites are produced using hypereutectic (17%Si) Al-Si alloy using centrifuge casting technique with SiC particulate(SiCP) as reinforcement using stir casting followed by centrifuge casting. The samples were characterized for microstructure, hardness, and wear. It was found that there is a gradation in the sample for all the above said properties from top to bottom of the sample. It was found that Al-17wt% Si matrix alloy reinforced with 2% SiCP yielded a maximum hardness of about 66BHN at 400rpm while for 4% and 6% the hardness was found to be 82 and 94BHN.The results revealed that the wear resistance was high at both the ends of the specimen due to segregation of Si at one end and SiCp at the other end.
Keywords: FG composite, Centrifuge casting, Microstructure, Hardness, Wear;