This study aims to examine the usability of environmentally harmless vegetable oil in the minimum quantity of lubrication(MQL)system in face milling of AISI O2 steel and to optimize the cutting parameters by different...This study aims to examine the usability of environmentally harmless vegetable oil in the minimum quantity of lubrication(MQL)system in face milling of AISI O2 steel and to optimize the cutting parameters by different statistical methods.Vegetable oil was preferred as cutting fluid,and Taguchi method was used in the preparation of the test pattern.After testing with the prepared test pattern,cutting performance in all parameters has been improved according to dry conditions thanks to the MQL system.The highest tool life was obtained by using cutting parameters of 7.5 m cutting length,100 m/min cutting speed,100 mL/h MQL flow rate and 0.1 mm/tooth feed rate.Optimum cutting parameters were determined according to the Taguchi analysis,and the obtained parameters were confirmed with the verification tests.In addition,the optimum test parameter was determined by applying the gray relational analysis method.After using ANOVA analysis according to the measured surface roughness and cutting force values,the most effective cutting parameter was observed to be the feed rate.In addition,the models for surface roughness and cutting force values were obtained with precisions of 99.63%and 99.68%,respectively.Effective wear mechanisms were found to be abrasion and adhesion.展开更多
The Taguchi and analysis of variance (ANOVA) methods were applied to investigate the effects of the structural and operational parameters on the heat transfer performance of a vertical sinter cooling packed bed. The a...The Taguchi and analysis of variance (ANOVA) methods were applied to investigate the effects of the structural and operational parameters on the heat transfer performance of a vertical sinter cooling packed bed. The analysed parameters were the gas flow rate, the air inlet temperature, the sinter inlet temperature, the cooling bed diameter and the cooling bed height, all of which contain three levels. The purpose was to improve the heat transfer performance of a vertical sinter cooling bed. A numerical analysis model was established to assess the heat transfer performance with respect to the varying parameters and their different levels. This mathematical model was validated by using data from practical industrial processes. The Taguchi method for the L27 (35) orthogonal design experiment was selected to evaluate the impacts of the design parameters on the heat transfer performance and to acquire the optimum combination of parameters. The analysis of variance was applied to assess the impact weights and the order of significance of the design parameters. The results show that the sinter inlet temperature and cooling bed diameter have great influences and impact the exergy of the wasted heat recovery by 61.65% and 23.31%, respectively. However, the gas flow rate and the air inlet temperature have small effects on the response. Furthermore, the air and sinter inlet temperatures have the most significant impacts on the efficiency of heat transfer by 68.83% and 23.31%, respectively. The optimal parameter combination (A1B1C3D3E3) was obtained, and the optimal results were validated by confirmation tests.展开更多
Mechanical properties of semi-solid casting are dependent on multiple processing parameters,and improper processing parameters will not only reduce mean data but also increase variations.The present study investigated...Mechanical properties of semi-solid casting are dependent on multiple processing parameters,and improper processing parameters will not only reduce mean data but also increase variations.The present study investigated the impact of parameters in slurry preparation and heat treatment on the yield strength and ductility of T6 heat-treated A356 Al-Si alloy using rapid slurry forming(RSF)semi-solid casting.The focus was primarily on the robustness of mechanical properties based on Taguchi design method.By analyzing signal-to-noise ratio and minimum value calculated from-3S,the optimum slurry preparation parameters and heat treatment parameters were determined to be no quench,enthalpy exchange material(EEM)temperature of 140℃,EEM-to-melt ratio of 6mass%,stirring time of 18 s,solution heat treated at 520℃ for 2 h,and ageing heat treated at 190℃ for 6 h.In a small batch validation,the-3S yield strength and-3S elongation reach 256.1 MPa and 5.03% respectively,showing a satisfactory robustness.The hardness and microstructure of heat-treated samples with the best and worst properties were characterized to gain insight into the underlying mechanisms affecting the mean value and variations of mechanical properties.展开更多
With the continuous improvement of permanent magnet(PM)wind generators'capacity and power density,the design of reasonable and efficient cooling structures has become a focus.This paper proposes a fully enclosed s...With the continuous improvement of permanent magnet(PM)wind generators'capacity and power density,the design of reasonable and efficient cooling structures has become a focus.This paper proposes a fully enclosed self-circulating hydrogen cooling structure for a originally forced-air-cooled direct-drive PM wind generator.The proposed hydrogen cooling system uses the rotor panel supports that hold the rotor core as the radial blades,and the hydrogen flow is driven by the rotating plates to flow through the axial and radial vents to realize the efficient cooling of the generator.According to the structural parameters of the cooling system,the Taguchi method is used to decouple the structural variables.The influence of the size of each cooling structure on the heat dissipation characteristic is analyzed,and the appropriate cooling structure scheme is determined.展开更多
In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries fa...In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries faces a significant challenge owing to the need to increase average electric power during charging. This challenge results from the direct influence of the power level on the rate of chemical reactions occurring in the battery electrodes. In this study, the Taguchi optimization method was used to enhance the average electric power during the charging process of lithium-ion batteries. The Taguchi technique is a statistical strategy that facilitates the systematic and efficient evaluation of numerous experimental variables. The proposed method involved varying seven input factors, including positive electrode thickness, positive electrode material, positive electrode active material volume fraction, negative electrode active material volume fraction, separator thickness, positive current collector thickness, and negative current collector thickness. Three levels were assigned to each control factor to identify the optimal conditions and maximize the average electric power during charging. Moreover, a variance assessment analysis was conducted to validate the results obtained from the Taguchi analysis. The results revealed that the Taguchi method was an eff ective approach for optimizing the average electric power during the charging of lithium-ion batteries. This indicates that the positive electrode material, followed by the separator thickness and the negative electrode active material volume fraction, was key factors significantly infl uencing the average electric power during the charging of lithium-ion batteries response. The identification of optimal conditions resulted in the improved performance of lithium-ion batteries, extending their potential in various applications. Particularly, lithium-ion batteries with average electric power of 16 W and 17 W during charging were designed and simulated in the range of 0-12000 s using COMSOL Multiphysics software. This study efficiently employs the Taguchi optimization technique to develop lithium-ion batteries capable of storing a predetermined average electric power during the charging phase. Therefore, this method enables the battery to achieve complete charging within a specific timeframe tailored to a specificapplication. The implementation of this method can save costs, time, and materials compared with other alternative methods, such as the trial-and-error approach.展开更多
Serpentine nozzles are widely used in combat aircraft to realize strong stealth characteristics.Based on the layout characteristics within a confined space,a series of double serpentine nozzles with spanwise offsets a...Serpentine nozzles are widely used in combat aircraft to realize strong stealth characteristics.Based on the layout characteristics within a confined space,a series of double serpentine nozzles with spanwise offsets are established.Using computational fluid dynamics and Taguchi method,the influence mechanisms of the Distribution of Area(DA),Distributions of Centerline for the first and second‘S’sections in the Vertical direction(DCV1 and DCV2),and Distribution of Centerline in the Spanwise direction(DCS)are analyzed.The impact of these factors on the total pressure recovery coefficient can be ranked as DA>DCV2>DCS>DCV1,whereas their impacts on the discharge coefficient and axial thrust coefficient can be ranked as DCV2>DCS>DA>DCV1.Considering the statistical significance of these factors,a nozzle in which DA changes rapidly at the exit and DCV1,DCV2,and DCS change rapidly at the entrance gives the best aerodynamic performance.Compared to the worst configuration,the total pressure recovery coefficient,discharge coefficient,and axial thrust coefficient are improved by 1.6%,3.5%and 3.6%,respectively.DA influences the gas flow acceleration in the entire serpentine channel,resulting in different wall shear stress and friction losses.The various centerline distributions influence the gas flow acceleration effects and form complex wave structures in the constantarea extension section,resulting in different local and friction losses.展开更多
Passive thermal management in electronics has disadvantages of low efficiency and high cost.Herein,experimental and numerical studies on the geometric optimization of a hygroscopic-membrane heat sink(HMHS)are conducte...Passive thermal management in electronics has disadvantages of low efficiency and high cost.Herein,experimental and numerical studies on the geometric optimization of a hygroscopic-membrane heat sink(HMHS)are conducted.The HMHS is based on water evaporation from a membrane-encapsulated hygroscopic salt solution,in which pin fins are used for thermal conductivity enhancement.A comprehensive heat and mass transfer model is developed and validated.To obtain the HMHS configuration with the maximum cooling performance,an approach that couples the Taguchi method with numerical simulations is utilized.The contribution ratio of each design factor is determined.Experimentally validated results demonstrate that the maximum temperature reduction provided by the HMHS can be further improved from 15.5℃to 17.8℃after optimization,achieving a temperature reduction of up to 21℃at a fixed heat flux of 25kW/m^(2)when compared with a similarly sized fin heat sink.Remarkably,the optimized HMHS extends the effective cooling time by∼343%compared with traditional phase-change materials,achieving a maximum temperature reduction ranging from 7.0℃to 20.4℃.Meanwhile,the effective heat transfer coefficient achieved is comparable with that of forced liquid cooling.Our findings suggest that the proposed cooling approach provides a new pathway for intermittent thermal management,which is expected to be used for thermal regulation of electronics,batteries,photovoltaic panels,and LED lights.展开更多
This paper presents an allowable-tolerance-based group search optimization(AT-GSO),which combines the robust GSO(R-GSO)and the external quality design planning of the Taguchi method.AT-GSO algorithm is used to optimiz...This paper presents an allowable-tolerance-based group search optimization(AT-GSO),which combines the robust GSO(R-GSO)and the external quality design planning of the Taguchi method.AT-GSO algorithm is used to optimize the heat transfer area of the heat exchanger system.The R-GSO algorithm integrates the GSO algorithm with the Taguchi method,utilizing the Taguchi method to determine the optimal producer in each iteration of the GSO algorithm to strengthen the robustness of the search process and the ability to find the global optima.In conventional parameter design optimization,it is typically assumed that the designed parameters can be applied accurately and consistently throughout usage.However,for systems that are sensitive to changes in design parameters,even minor inaccuracies can substantially reduce overall system performance.Therefore,the permissible variations of the design parameters are considered in the tolerance-optimized design to ensure the robustness of the performance.The optimized design of the heat exchanger system assumes that the system’s operating temperature parameters are specific.However,fixing the systemoperating temperature parameters at a constant value is difficult.This paper assumes that the system operating temperature parameters have an uncertainty error when optimizing the heat transfer area of the heat exchanger system.Experimental results show that the AT-GSO algorithm optimizes the heat exchanger system and finds the optimal operating temperature in the absence of tolerance and under three tolerance conditions.展开更多
Dielectric elastomer actuator （DEA） show promise for mechatronic applications due to the advantages of dielectric elastomer, such as lightweight, flexible, low cost, high strain, etc, and many configurations of DEAs...Dielectric elastomer actuator （DEA） show promise for mechatronic applications due to the advantages of dielectric elastomer, such as lightweight, flexible, low cost, high strain, etc, and many configurations of DEAs have been demonstrated. As a kind of linear actuator, cone DEAs are studied in some laboratory prototypes due to easy manufacturing, however, their performance have not been exploited fully. Based on the working principle of DEA, a four-bar linkage mechanism is designed to provide negative stiffness preload, which can increase displacement output of actuator （outer diameter 100 mm） to 17 mm. Three cone actuating units are assembled in parallel to enhance the maximum force output to 5.07 N. Loading experiments of actuator in forward and backward strokes are performed, the experimental results show that backward stroke has stronger actuating capability than forward stroke, accordingly application of actuator is recommended. Four factors rather than applied voltage, i.e., number of actuating units, pre-stretch ratio, inner diameter, and outer diameter, are determined as influencing factors for Taguchi method. Then the performance objectives of actuator, i.e., displacement output, maximum force output, and maximum work in backward stroke, are investigated based on L9（34） Taguchi orthogonal design. The mean signal-to-noise （S/N） ratio based on the larger-the-better criterion is calculated according to the acquired displacement and force output. Analytical results show that outer diameter has the most significant influence on displacement output, and maximum force out and work output are influenced most by number of actuating units. Inner diameter also has an important effect on the performance objectives of actuator, while pre-stretch ratio has the least influence. The proposed performance investigation is helpful for the design and application of cone actuator in mechatronic system.展开更多
An attempt has been made to study the influence of wear parameters like applied load, sliding speed, sliding distance and percentage of reinforcement on the dry sliding wear of the metal matrix composites. A plan of e...An attempt has been made to study the influence of wear parameters like applied load, sliding speed, sliding distance and percentage of reinforcement on the dry sliding wear of the metal matrix composites. A plan of experiments, based on techniques of Taguchi, was performed to acquire data in controlled way. An orthogonal array and the analysis of variance were employed to investigate the influence of process parameters on the wear of composites. The objective is to establish a correlation between dry sliding wear of composites and wear parameters. These correlations were obtained by multiple regressions. Finally, confirmation tests were conducted to verify the experimental results foreseen from the mentioned correlations.展开更多
Chemical mechanical polishing （CMP） was used to polish Lithium triborate （LiB3O5 or LBO） crystal. Taguchi method was applied for optimization of the polishing parameters. Material removal rate （MRR） and surface ...Chemical mechanical polishing （CMP） was used to polish Lithium triborate （LiB3O5 or LBO） crystal. Taguchi method was applied for optimization of the polishing parameters. Material removal rate （MRR） and surface roughness are considered as criteria for the optimization. The polishing pressure, the abrasive concentration and the table velocity are important parameters which influence MRR and surface roughness in CMP of LBO crystal. Experiment results indicate that for MRR the polishing pressure is the most significant polishing parameter followed by table velocity; while for the surface roughness, the abrasive concentration is the most important one. For high MRR in CMP of LBO ctystal the optimal conditions are： pressure 620 g/cm^2, concentration 5.0 wt pct, and velocity 60 r/min, respectively. For the best surface roughness the optimal conditions are： pressure 416 g/cm^2, concentration 5.0 wt pct, and velocity 40 r/min, respectively. The contributions of individual parameters for MRR and surface roughness were obtained.展开更多
The neutral zinc sulfate solution obtained from hydrometallurgical process of Angouran zinc concentrate has cadmium, nickel and cobalt impurities, that must be purified before electrowinning. Therefore, cadmium and ni...The neutral zinc sulfate solution obtained from hydrometallurgical process of Angouran zinc concentrate has cadmium, nickel and cobalt impurities, that must be purified before electrowinning. Therefore, cadmium and nickel are usually cemented out by addition of zinc dust and remained nickel and cobalt cemented out at second stage with zinc powder and arsenic trioxide. In this research, a new approach is described for determination of effective parameters and optimization of zinc electrolyte hot purification process using statistical design of experiments. The Taguchi method based on orthogonal array design（OAD） has been used to arrange the experimental runs. The experimental conditions involved in the work are as follows： the temperature range of 70-90 ℃ for reaction temperature（T）, 30-90 min for reaction time（t）, 2-4 g/L for zinc powder mass concentration（M）, one to five series for zinc dust particle size distributions（S1-S5）, and 0.1-0.5 g/L（C） for arsenic trioxide mass concentration. Optimum conditions for hot purification obtained in this work are T4（85 ℃）, t4=75 min, M4=3.5 g/L, S4（Serie 4）, and C2=0.2 g/L.展开更多
The present research work emphasized on identifying and optimizing various significant process parameters of high pressure die casting by using QFD-Taguchi based hybrid approach in order to yield the optimum casting d...The present research work emphasized on identifying and optimizing various significant process parameters of high pressure die casting by using QFD-Taguchi based hybrid approach in order to yield the optimum casting density of the A380alloy.Identification of critical process parameters,selection of appropriate orthogonal array,analysis of means and analysis of variance are employed to study the performance characteristic of the die casting process.The most critical process parameters identified and optimized by QFD-Taguchi based hybrid approach,such as the injection pressure,the molten metal temperature,the plunger velocity(first and second stage)and the die temperature were explored in the experimental work.The results show that injection pressure is the most significant factor among the selected parameters.The contribution of the injection pressure to the variation of mean casting density is around61.483%.Confidence interval(CI)has also been estimated as0.000718for95%consistency level to validate the predicted range of optimum casting density of aforesaid alloy.展开更多
A series of different transition metals(V,Co,Cr,Mn,Fe,Ni,Cu and Zn) promoted H-ZSM-5 catalysts were prepared by impregnation method and characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM) and tra...A series of different transition metals(V,Co,Cr,Mn,Fe,Ni,Cu and Zn) promoted H-ZSM-5 catalysts were prepared by impregnation method and characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The catalytic activity of these catalysts was evaluated for the selective catalytic reduction(SCR) of NO with NH_3 as reductant in the presence of oxygen.The results revealed that the catalytic activity of Cu-ZSM-5 nanocatalyst for NO conversion to N_2 was 80%at 300 ℃,which was the best among various promoted metals.Design of experiments(DOEs) with Taguchi method was employed to optimize NH_3-SCR process parameters such as NH_3/NO ratio,O_2 concentration,and gas hourly space velocity(GHSV) over Cu-ZSM-5 nanocatalyst at 250 and 300 ℃.Results showed that the most important parameter in NH_3-SCR of NO is O_2 concentration;followed by NH_3/NO ratio and GHSV has little importance.The NO conversion to N_2 of 63.1%and 94.86%was observed at 250℃ and 300℃,respectively under the obtained optimum conditions.展开更多
An efficient approach was introduced for improving the condition of major controlled rolling process pa- rameters of roughing, finishing and coiling temperatures and optimizing these parameters to obtain minimum grain...An efficient approach was introduced for improving the condition of major controlled rolling process pa- rameters of roughing, finishing and coiling temperatures and optimizing these parameters to obtain minimum grain size and maximum dome height simultaneously. Taguchi method combined with grey relational analysis was applied to achieve optimum grain size and dome height during controlled rolling process. For this purpose, four levels for the above temperatures were chosen and sixteen experiments were conducted based on orthogonal array of Taguchi meth- od. Based on Taguchi approach, signal-to-noise （S/N） ratios were calculated and used in order to obtain the opti- mum levels for every input parameter. Analysis of variance revealed that finishing and coiling temperatures have the maximum effect on the grain size and dome height of microalloyed steels. The confirmation tests with the optimal levels of parameters indicated that the grain size and dome height of controlled rolled microalloyed steels can be im- proved effectively through this approach.展开更多
Particle swarm optimization （PSO）, like other evolutionary algorithms is a population-based stochastic algorithm inspired from the metaphor of social interaction in birds, insects, wasps, etc. It has been used for f...Particle swarm optimization （PSO）, like other evolutionary algorithms is a population-based stochastic algorithm inspired from the metaphor of social interaction in birds, insects, wasps, etc. It has been used for finding promising solutions in complex search space through the interaction of particles in a swarm. It is a well recognized fact that the performance of evolutionary algorithms to a great extent depends on the choice of appropriate strategy/operating parameters like population size, crossover rate, mutation rate, crossover operator, etc. Generally, these parameters are selected through hit and trial process, which is very unsystematic and requires rigorous experimentation. This paper proposes a systematic based on Taguchi method reasoning scheme for rapidly identifying the strategy parameters for the PSO algorithm. The Taguchi method is a robust design approach using fractional factorial design to study a large number of parameters with small number of experiments. Computer simulations have been performed on two benchmark functionsiRosenbrock function and Griewank functionito validate the approach.展开更多
The fabrication of high strength Al 7068？5%TiC （mass fraction） nanocomposite was studied by mechanical alloying and hot pressing routes. Considering densification importance and grain growth effects, hot pressing p...The fabrication of high strength Al 7068？5%TiC （mass fraction） nanocomposite was studied by mechanical alloying and hot pressing routes. Considering densification importance and grain growth effects, hot pressing process conditions for producing bulk nanocomposite were optimized using statistical Taguchi method based on compressive strength achievement. The Taguchi results indicate that 30 min hot pressing under pressure of 500 MPa at 385 °C provides high compressive strength and hardness of 938 MPa and HV 265, respectively. More interestingly, analysis of variance proves that the applied pressure is the most influential factor for hot pressing of the nanocomposite. The contribution percentages of factors in hot pressing terms are as follows： applied pressure （61.3%）, exposed temperature （29.53%） and dwelling hot pressing time （4.49%）.展开更多
The application of new soft magnetic materials in permanent magnet motor can effectively reduce the loss of motor and improve the efficiency of motor. Taguchi method is a local multivariable and multi-objective optimi...The application of new soft magnetic materials in permanent magnet motor can effectively reduce the loss of motor and improve the efficiency of motor. Taguchi method is a local multivariable and multi-objective optimization method widely used in various engineering problems, which can effectively improve the efficiency of engineering optimization. In this paper, based on a 25 kW, 1700 r/min three-phase permanent magnet motor, the relevant motor model is established in the finite element simulation software, and the relevant simulation analysis is carried out. Combined with Taguchi method optimization, the local optimal structure scheme is obtained. Through optimization, the motor can maintain high efficiency, reduce the cogging torque of the motor by 53.45%, reduce the torque ripple by 36.79%, and increase the torque generated by the permanent magnet per unit mass by 21.42%. Through this optimization, the overall performance of the motor has been significantly improved. The research content of this paper verifies the feasibility of the application of Taguchi method in the optimization of new soft magnetic material motor, provides a new idea for the optimization design of new soft magnetic material motor, and also provides a certain reference for the local multi-objective optimization of the electromagnetic structure of other similar motors.展开更多
In this paper,a 20kW vehicle built-in permanent magnet synchronous motor is taken as an example,and a magnetic barrier structure is added to the rotor of the motor to solve the uneven saturation problem of the rotor s...In this paper,a 20kW vehicle built-in permanent magnet synchronous motor is taken as an example,and a magnetic barrier structure is added to the rotor of the motor to solve the uneven saturation problem of the rotor side magnetic bridge.This structure improves the air-gap flux density waveform of the motor by influencing the internal magnetic flux path of the motor rotor,thus improving the sine of the no-load back EMF waveform of the motor and reducing the torque ripple of the motor.At the same time,Taguchi method is used to optimize the structural parameters of the added magnetic barrier.In order to facilitate the analysis of its uneven saturation phenomenon and improve the optimization effect,a simple equivalent magnetic network(EMN)model considering the uneven saturation of rotor magnetic bridge is established in this paper,and the initial values of optimization factors are selected based on this model.Finally,the no-load back EMF waveform distortion rate,torque ripple and output torque of the optimized motor are compared and analyzed,and the influence of magnetic barrier structure parameters on the electromagnetic performance of the motor is also analyzed.The results show that the optimized motor can not change the output torque of the motor as much as possible on the basis of reducing the waveform distortion rate of no-load back EMF and torque ripple.展开更多
Taguchi method has been employed to investigate the effects of cutting fluids on surface roughness in turning AISI 1330 alloy steel, using manually operated lathe machine. Experiments have been conducted using L<su...Taguchi method has been employed to investigate the effects of cutting fluids on surface roughness in turning AISI 1330 alloy steel, using manually operated lathe machine. Experiments have been conducted using L<sub>27 </sub>(3<sup>4</sup>) orthogonal array and each experiment was repeated three times and each test used a new cutting tool, High Speed Steel (HSS), to ensure accurate readings of the surface roughness. The statistical methods of Signal-to-Noise (S/N) ratio and the Analysis of Variance (ANOVA) were applied to investigate effects of cutting speed, feed rate and depth of cut on surface roughness under different cutting fluids. Minitab 14 software was used to analyze the effect of variables on the surface roughness. Results obtained indicated that optimal variables for the minimum surface roughness were cutting speed of 35 m/min (level 2), feed of 0.124 mm/rev (level 1), depth of cut of 0.3 mm (level 1) and a cutting fluid with a viscosity of 2.898 mm<sup>2</sup>/s (level 3). Hence, the optimal parameters to obtain better surface roughness of the workpiece material were obtained when groundnut oil based cutting fluid was used. Analysis of variance shows that feed rate has the most significant effect on surface roughness.展开更多
文摘This study aims to examine the usability of environmentally harmless vegetable oil in the minimum quantity of lubrication(MQL)system in face milling of AISI O2 steel and to optimize the cutting parameters by different statistical methods.Vegetable oil was preferred as cutting fluid,and Taguchi method was used in the preparation of the test pattern.After testing with the prepared test pattern,cutting performance in all parameters has been improved according to dry conditions thanks to the MQL system.The highest tool life was obtained by using cutting parameters of 7.5 m cutting length,100 m/min cutting speed,100 mL/h MQL flow rate and 0.1 mm/tooth feed rate.Optimum cutting parameters were determined according to the Taguchi analysis,and the obtained parameters were confirmed with the verification tests.In addition,the optimum test parameter was determined by applying the gray relational analysis method.After using ANOVA analysis according to the measured surface roughness and cutting force values,the most effective cutting parameter was observed to be the feed rate.In addition,the models for surface roughness and cutting force values were obtained with precisions of 99.63%and 99.68%,respectively.Effective wear mechanisms were found to be abrasion and adhesion.
基金This work is supported by the National Key R&D Program of China(2017 YFB0304200)the National Natural Science Foundation of China(51734004).
文摘The Taguchi and analysis of variance (ANOVA) methods were applied to investigate the effects of the structural and operational parameters on the heat transfer performance of a vertical sinter cooling packed bed. The analysed parameters were the gas flow rate, the air inlet temperature, the sinter inlet temperature, the cooling bed diameter and the cooling bed height, all of which contain three levels. The purpose was to improve the heat transfer performance of a vertical sinter cooling bed. A numerical analysis model was established to assess the heat transfer performance with respect to the varying parameters and their different levels. This mathematical model was validated by using data from practical industrial processes. The Taguchi method for the L27 (35) orthogonal design experiment was selected to evaluate the impacts of the design parameters on the heat transfer performance and to acquire the optimum combination of parameters. The analysis of variance was applied to assess the impact weights and the order of significance of the design parameters. The results show that the sinter inlet temperature and cooling bed diameter have great influences and impact the exergy of the wasted heat recovery by 61.65% and 23.31%, respectively. However, the gas flow rate and the air inlet temperature have small effects on the response. Furthermore, the air and sinter inlet temperatures have the most significant impacts on the efficiency of heat transfer by 68.83% and 23.31%, respectively. The optimal parameter combination (A1B1C3D3E3) was obtained, and the optimal results were validated by confirmation tests.
文摘Mechanical properties of semi-solid casting are dependent on multiple processing parameters,and improper processing parameters will not only reduce mean data but also increase variations.The present study investigated the impact of parameters in slurry preparation and heat treatment on the yield strength and ductility of T6 heat-treated A356 Al-Si alloy using rapid slurry forming(RSF)semi-solid casting.The focus was primarily on the robustness of mechanical properties based on Taguchi design method.By analyzing signal-to-noise ratio and minimum value calculated from-3S,the optimum slurry preparation parameters and heat treatment parameters were determined to be no quench,enthalpy exchange material(EEM)temperature of 140℃,EEM-to-melt ratio of 6mass%,stirring time of 18 s,solution heat treated at 520℃ for 2 h,and ageing heat treated at 190℃ for 6 h.In a small batch validation,the-3S yield strength and-3S elongation reach 256.1 MPa and 5.03% respectively,showing a satisfactory robustness.The hardness and microstructure of heat-treated samples with the best and worst properties were characterized to gain insight into the underlying mechanisms affecting the mean value and variations of mechanical properties.
基金supported in part by the“Chunhui Plan”Collaborative Research Project of Chinese Ministry of Education under Grant HZKY20220604by the National Natural Science Foundation of China under Grant 52107007。
文摘With the continuous improvement of permanent magnet(PM)wind generators'capacity and power density,the design of reasonable and efficient cooling structures has become a focus.This paper proposes a fully enclosed self-circulating hydrogen cooling structure for a originally forced-air-cooled direct-drive PM wind generator.The proposed hydrogen cooling system uses the rotor panel supports that hold the rotor core as the radial blades,and the hydrogen flow is driven by the rotating plates to flow through the axial and radial vents to realize the efficient cooling of the generator.According to the structural parameters of the cooling system,the Taguchi method is used to decouple the structural variables.The influence of the size of each cooling structure on the heat dissipation characteristic is analyzed,and the appropriate cooling structure scheme is determined.
文摘In recent times, lithium-ion batteries have been widely used owing to their high energy density, extended cycle lifespan, and minimal self-discharge rate. The design of high-speed rechargeable lithium-ion batteries faces a significant challenge owing to the need to increase average electric power during charging. This challenge results from the direct influence of the power level on the rate of chemical reactions occurring in the battery electrodes. In this study, the Taguchi optimization method was used to enhance the average electric power during the charging process of lithium-ion batteries. The Taguchi technique is a statistical strategy that facilitates the systematic and efficient evaluation of numerous experimental variables. The proposed method involved varying seven input factors, including positive electrode thickness, positive electrode material, positive electrode active material volume fraction, negative electrode active material volume fraction, separator thickness, positive current collector thickness, and negative current collector thickness. Three levels were assigned to each control factor to identify the optimal conditions and maximize the average electric power during charging. Moreover, a variance assessment analysis was conducted to validate the results obtained from the Taguchi analysis. The results revealed that the Taguchi method was an eff ective approach for optimizing the average electric power during the charging of lithium-ion batteries. This indicates that the positive electrode material, followed by the separator thickness and the negative electrode active material volume fraction, was key factors significantly infl uencing the average electric power during the charging of lithium-ion batteries response. The identification of optimal conditions resulted in the improved performance of lithium-ion batteries, extending their potential in various applications. Particularly, lithium-ion batteries with average electric power of 16 W and 17 W during charging were designed and simulated in the range of 0-12000 s using COMSOL Multiphysics software. This study efficiently employs the Taguchi optimization technique to develop lithium-ion batteries capable of storing a predetermined average electric power during the charging phase. Therefore, this method enables the battery to achieve complete charging within a specific timeframe tailored to a specificapplication. The implementation of this method can save costs, time, and materials compared with other alternative methods, such as the trial-and-error approach.
基金supported by the National Science and Technology Major Project of China(No.J2019-III-0009-0053).
文摘Serpentine nozzles are widely used in combat aircraft to realize strong stealth characteristics.Based on the layout characteristics within a confined space,a series of double serpentine nozzles with spanwise offsets are established.Using computational fluid dynamics and Taguchi method,the influence mechanisms of the Distribution of Area(DA),Distributions of Centerline for the first and second‘S’sections in the Vertical direction(DCV1 and DCV2),and Distribution of Centerline in the Spanwise direction(DCS)are analyzed.The impact of these factors on the total pressure recovery coefficient can be ranked as DA>DCV2>DCS>DCV1,whereas their impacts on the discharge coefficient and axial thrust coefficient can be ranked as DCV2>DCS>DA>DCV1.Considering the statistical significance of these factors,a nozzle in which DA changes rapidly at the exit and DCV1,DCV2,and DCS change rapidly at the entrance gives the best aerodynamic performance.Compared to the worst configuration,the total pressure recovery coefficient,discharge coefficient,and axial thrust coefficient are improved by 1.6%,3.5%and 3.6%,respectively.DA influences the gas flow acceleration in the entire serpentine channel,resulting in different wall shear stress and friction losses.The various centerline distributions influence the gas flow acceleration effects and form complex wave structures in the constantarea extension section,resulting in different local and friction losses.
基金National Natural Science Foundation of China,Grant/Award Number:52322812Shenzhen Science and Technology Program,Grant/Award Number:JCYJ20230807114905012Research Grants Council of Hong Kong,Grant/Award Numbers:CityU 11215621,CityU 11218922。
文摘Passive thermal management in electronics has disadvantages of low efficiency and high cost.Herein,experimental and numerical studies on the geometric optimization of a hygroscopic-membrane heat sink(HMHS)are conducted.The HMHS is based on water evaporation from a membrane-encapsulated hygroscopic salt solution,in which pin fins are used for thermal conductivity enhancement.A comprehensive heat and mass transfer model is developed and validated.To obtain the HMHS configuration with the maximum cooling performance,an approach that couples the Taguchi method with numerical simulations is utilized.The contribution ratio of each design factor is determined.Experimentally validated results demonstrate that the maximum temperature reduction provided by the HMHS can be further improved from 15.5℃to 17.8℃after optimization,achieving a temperature reduction of up to 21℃at a fixed heat flux of 25kW/m^(2)when compared with a similarly sized fin heat sink.Remarkably,the optimized HMHS extends the effective cooling time by∼343%compared with traditional phase-change materials,achieving a maximum temperature reduction ranging from 7.0℃to 20.4℃.Meanwhile,the effective heat transfer coefficient achieved is comparable with that of forced liquid cooling.Our findings suggest that the proposed cooling approach provides a new pathway for intermittent thermal management,which is expected to be used for thermal regulation of electronics,batteries,photovoltaic panels,and LED lights.
基金funded by the National Science and Technology Council,Taiwan,under Grant Number MOST110-2221-E035-092-MY3.
文摘This paper presents an allowable-tolerance-based group search optimization(AT-GSO),which combines the robust GSO(R-GSO)and the external quality design planning of the Taguchi method.AT-GSO algorithm is used to optimize the heat transfer area of the heat exchanger system.The R-GSO algorithm integrates the GSO algorithm with the Taguchi method,utilizing the Taguchi method to determine the optimal producer in each iteration of the GSO algorithm to strengthen the robustness of the search process and the ability to find the global optima.In conventional parameter design optimization,it is typically assumed that the designed parameters can be applied accurately and consistently throughout usage.However,for systems that are sensitive to changes in design parameters,even minor inaccuracies can substantially reduce overall system performance.Therefore,the permissible variations of the design parameters are considered in the tolerance-optimized design to ensure the robustness of the performance.The optimized design of the heat exchanger system assumes that the system’s operating temperature parameters are specific.However,fixing the systemoperating temperature parameters at a constant value is difficult.This paper assumes that the system operating temperature parameters have an uncertainty error when optimizing the heat transfer area of the heat exchanger system.Experimental results show that the AT-GSO algorithm optimizes the heat exchanger system and finds the optimal operating temperature in the absence of tolerance and under three tolerance conditions.
基金supported by National Natural Science Foundation of China (Grant No. 50975139, Grant No. 50605031)Provincial Natural Science Foundation of Jiangsu, China (Grant No. 2008395)+1 种基金Foundation of State Key Laboratory of Robotics, China (Grant No. RLO200912)China Postdoctoral Science Foundation (Grant No. 20080441319, Grant No. 200902684)
文摘Dielectric elastomer actuator （DEA） show promise for mechatronic applications due to the advantages of dielectric elastomer, such as lightweight, flexible, low cost, high strain, etc, and many configurations of DEAs have been demonstrated. As a kind of linear actuator, cone DEAs are studied in some laboratory prototypes due to easy manufacturing, however, their performance have not been exploited fully. Based on the working principle of DEA, a four-bar linkage mechanism is designed to provide negative stiffness preload, which can increase displacement output of actuator （outer diameter 100 mm） to 17 mm. Three cone actuating units are assembled in parallel to enhance the maximum force output to 5.07 N. Loading experiments of actuator in forward and backward strokes are performed, the experimental results show that backward stroke has stronger actuating capability than forward stroke, accordingly application of actuator is recommended. Four factors rather than applied voltage, i.e., number of actuating units, pre-stretch ratio, inner diameter, and outer diameter, are determined as influencing factors for Taguchi method. Then the performance objectives of actuator, i.e., displacement output, maximum force output, and maximum work in backward stroke, are investigated based on L9（34） Taguchi orthogonal design. The mean signal-to-noise （S/N） ratio based on the larger-the-better criterion is calculated according to the acquired displacement and force output. Analytical results show that outer diameter has the most significant influence on displacement output, and maximum force out and work output are influenced most by number of actuating units. Inner diameter also has an important effect on the performance objectives of actuator, while pre-stretch ratio has the least influence. The proposed performance investigation is helpful for the design and application of cone actuator in mechatronic system.
文摘An attempt has been made to study the influence of wear parameters like applied load, sliding speed, sliding distance and percentage of reinforcement on the dry sliding wear of the metal matrix composites. A plan of experiments, based on techniques of Taguchi, was performed to acquire data in controlled way. An orthogonal array and the analysis of variance were employed to investigate the influence of process parameters on the wear of composites. The objective is to establish a correlation between dry sliding wear of composites and wear parameters. These correlations were obtained by multiple regressions. Finally, confirmation tests were conducted to verify the experimental results foreseen from the mentioned correlations.
基金supported by the National Natural Science Foundation of China(No.50675104 and 50905086)Six High Talent Fund of Jiangsu Province(No.06-D-024)Talent Fund of NUAA(No.S0782-052)
文摘Chemical mechanical polishing （CMP） was used to polish Lithium triborate （LiB3O5 or LBO） crystal. Taguchi method was applied for optimization of the polishing parameters. Material removal rate （MRR） and surface roughness are considered as criteria for the optimization. The polishing pressure, the abrasive concentration and the table velocity are important parameters which influence MRR and surface roughness in CMP of LBO crystal. Experiment results indicate that for MRR the polishing pressure is the most significant polishing parameter followed by table velocity; while for the surface roughness, the abrasive concentration is the most important one. For high MRR in CMP of LBO ctystal the optimal conditions are： pressure 620 g/cm^2, concentration 5.0 wt pct, and velocity 60 r/min, respectively. For the best surface roughness the optimal conditions are： pressure 416 g/cm^2, concentration 5.0 wt pct, and velocity 40 r/min, respectively. The contributions of individual parameters for MRR and surface roughness were obtained.
文摘The neutral zinc sulfate solution obtained from hydrometallurgical process of Angouran zinc concentrate has cadmium, nickel and cobalt impurities, that must be purified before electrowinning. Therefore, cadmium and nickel are usually cemented out by addition of zinc dust and remained nickel and cobalt cemented out at second stage with zinc powder and arsenic trioxide. In this research, a new approach is described for determination of effective parameters and optimization of zinc electrolyte hot purification process using statistical design of experiments. The Taguchi method based on orthogonal array design（OAD） has been used to arrange the experimental runs. The experimental conditions involved in the work are as follows： the temperature range of 70-90 ℃ for reaction temperature（T）, 30-90 min for reaction time（t）, 2-4 g/L for zinc powder mass concentration（M）, one to five series for zinc dust particle size distributions（S1-S5）, and 0.1-0.5 g/L（C） for arsenic trioxide mass concentration. Optimum conditions for hot purification obtained in this work are T4（85 ℃）, t4=75 min, M4=3.5 g/L, S4（Serie 4）, and C2=0.2 g/L.
基金the National Institute of Technology,Manipur,Imphal for Financial Support to carry out the experimental work of Mr.K.Ch.Apparao
文摘The present research work emphasized on identifying and optimizing various significant process parameters of high pressure die casting by using QFD-Taguchi based hybrid approach in order to yield the optimum casting density of the A380alloy.Identification of critical process parameters,selection of appropriate orthogonal array,analysis of means and analysis of variance are employed to study the performance characteristic of the die casting process.The most critical process parameters identified and optimized by QFD-Taguchi based hybrid approach,such as the injection pressure,the molten metal temperature,the plunger velocity(first and second stage)and the die temperature were explored in the experimental work.The results show that injection pressure is the most significant factor among the selected parameters.The contribution of the injection pressure to the variation of mean casting density is around61.483%.Confidence interval(CI)has also been estimated as0.000718for95%consistency level to validate the predicted range of optimum casting density of aforesaid alloy.
基金financial support from University of Tabriz and Iranian Nanotechnology Initiative
文摘A series of different transition metals(V,Co,Cr,Mn,Fe,Ni,Cu and Zn) promoted H-ZSM-5 catalysts were prepared by impregnation method and characterized by X-ray diffraction(XRD),scanning electron microscopy(SEM) and transmission electron microscopy(TEM).The catalytic activity of these catalysts was evaluated for the selective catalytic reduction(SCR) of NO with NH_3 as reductant in the presence of oxygen.The results revealed that the catalytic activity of Cu-ZSM-5 nanocatalyst for NO conversion to N_2 was 80%at 300 ℃,which was the best among various promoted metals.Design of experiments(DOEs) with Taguchi method was employed to optimize NH_3-SCR process parameters such as NH_3/NO ratio,O_2 concentration,and gas hourly space velocity(GHSV) over Cu-ZSM-5 nanocatalyst at 250 and 300 ℃.Results showed that the most important parameter in NH_3-SCR of NO is O_2 concentration;followed by NH_3/NO ratio and GHSV has little importance.The NO conversion to N_2 of 63.1%and 94.86%was observed at 250℃ and 300℃,respectively under the obtained optimum conditions.
文摘An efficient approach was introduced for improving the condition of major controlled rolling process pa- rameters of roughing, finishing and coiling temperatures and optimizing these parameters to obtain minimum grain size and maximum dome height simultaneously. Taguchi method combined with grey relational analysis was applied to achieve optimum grain size and dome height during controlled rolling process. For this purpose, four levels for the above temperatures were chosen and sixteen experiments were conducted based on orthogonal array of Taguchi meth- od. Based on Taguchi approach, signal-to-noise （S/N） ratios were calculated and used in order to obtain the opti- mum levels for every input parameter. Analysis of variance revealed that finishing and coiling temperatures have the maximum effect on the grain size and dome height of microalloyed steels. The confirmation tests with the optimal levels of parameters indicated that the grain size and dome height of controlled rolled microalloyed steels can be im- proved effectively through this approach.
文摘Particle swarm optimization （PSO）, like other evolutionary algorithms is a population-based stochastic algorithm inspired from the metaphor of social interaction in birds, insects, wasps, etc. It has been used for finding promising solutions in complex search space through the interaction of particles in a swarm. It is a well recognized fact that the performance of evolutionary algorithms to a great extent depends on the choice of appropriate strategy/operating parameters like population size, crossover rate, mutation rate, crossover operator, etc. Generally, these parameters are selected through hit and trial process, which is very unsystematic and requires rigorous experimentation. This paper proposes a systematic based on Taguchi method reasoning scheme for rapidly identifying the strategy parameters for the PSO algorithm. The Taguchi method is a robust design approach using fractional factorial design to study a large number of parameters with small number of experiments. Computer simulations have been performed on two benchmark functionsiRosenbrock function and Griewank functionito validate the approach.
文摘The fabrication of high strength Al 7068？5%TiC （mass fraction） nanocomposite was studied by mechanical alloying and hot pressing routes. Considering densification importance and grain growth effects, hot pressing process conditions for producing bulk nanocomposite were optimized using statistical Taguchi method based on compressive strength achievement. The Taguchi results indicate that 30 min hot pressing under pressure of 500 MPa at 385 °C provides high compressive strength and hardness of 938 MPa and HV 265, respectively. More interestingly, analysis of variance proves that the applied pressure is the most influential factor for hot pressing of the nanocomposite. The contribution percentages of factors in hot pressing terms are as follows： applied pressure （61.3%）, exposed temperature （29.53%） and dwelling hot pressing time （4.49%）.
文摘The application of new soft magnetic materials in permanent magnet motor can effectively reduce the loss of motor and improve the efficiency of motor. Taguchi method is a local multivariable and multi-objective optimization method widely used in various engineering problems, which can effectively improve the efficiency of engineering optimization. In this paper, based on a 25 kW, 1700 r/min three-phase permanent magnet motor, the relevant motor model is established in the finite element simulation software, and the relevant simulation analysis is carried out. Combined with Taguchi method optimization, the local optimal structure scheme is obtained. Through optimization, the motor can maintain high efficiency, reduce the cogging torque of the motor by 53.45%, reduce the torque ripple by 36.79%, and increase the torque generated by the permanent magnet per unit mass by 21.42%. Through this optimization, the overall performance of the motor has been significantly improved. The research content of this paper verifies the feasibility of the application of Taguchi method in the optimization of new soft magnetic material motor, provides a new idea for the optimization design of new soft magnetic material motor, and also provides a certain reference for the local multi-objective optimization of the electromagnetic structure of other similar motors.
基金supported by the National Natural Science Funds of China No.51907129Technology program of Liaoning province No.2021-MS-236。
文摘In this paper,a 20kW vehicle built-in permanent magnet synchronous motor is taken as an example,and a magnetic barrier structure is added to the rotor of the motor to solve the uneven saturation problem of the rotor side magnetic bridge.This structure improves the air-gap flux density waveform of the motor by influencing the internal magnetic flux path of the motor rotor,thus improving the sine of the no-load back EMF waveform of the motor and reducing the torque ripple of the motor.At the same time,Taguchi method is used to optimize the structural parameters of the added magnetic barrier.In order to facilitate the analysis of its uneven saturation phenomenon and improve the optimization effect,a simple equivalent magnetic network(EMN)model considering the uneven saturation of rotor magnetic bridge is established in this paper,and the initial values of optimization factors are selected based on this model.Finally,the no-load back EMF waveform distortion rate,torque ripple and output torque of the optimized motor are compared and analyzed,and the influence of magnetic barrier structure parameters on the electromagnetic performance of the motor is also analyzed.The results show that the optimized motor can not change the output torque of the motor as much as possible on the basis of reducing the waveform distortion rate of no-load back EMF and torque ripple.
文摘Taguchi method has been employed to investigate the effects of cutting fluids on surface roughness in turning AISI 1330 alloy steel, using manually operated lathe machine. Experiments have been conducted using L<sub>27 </sub>(3<sup>4</sup>) orthogonal array and each experiment was repeated three times and each test used a new cutting tool, High Speed Steel (HSS), to ensure accurate readings of the surface roughness. The statistical methods of Signal-to-Noise (S/N) ratio and the Analysis of Variance (ANOVA) were applied to investigate effects of cutting speed, feed rate and depth of cut on surface roughness under different cutting fluids. Minitab 14 software was used to analyze the effect of variables on the surface roughness. Results obtained indicated that optimal variables for the minimum surface roughness were cutting speed of 35 m/min (level 2), feed of 0.124 mm/rev (level 1), depth of cut of 0.3 mm (level 1) and a cutting fluid with a viscosity of 2.898 mm<sup>2</sup>/s (level 3). Hence, the optimal parameters to obtain better surface roughness of the workpiece material were obtained when groundnut oil based cutting fluid was used. Analysis of variance shows that feed rate has the most significant effect on surface roughness.
