Response Surface Method Optimization Research Articles

Comparative evaluation between Taguchi method and response surface method for optimization of electrocoagulation process in the context of treatment of dairy industry wastewater.

The presence of a large amount of organic and inorganic pollutants in dairy effluent is a substantial environmental issue. This study investigated electrocoagulation (EC) as a potential treatment method for dairy wastewater under different operating conditions, such as applied voltage (5-25V), electrolysis time (30-90min), and inter-electrode distance (1-2cm) by using aluminum electrodes. This study focuses on achieving the maximum removal of BOD, COD, and nitrate in dairy effluents with the aforementioned operating conditions. The process was optimized using the response surface methodology (RSM) and Taguchi method. RSM method optimized the electrocoagulation operating conditions such as the voltage at 23.75V, time of 90min, and inter-electrode distance at 1.07cm. This optimization achieved the maximum removal percentage of BOD, COD, and nitrate at 79.06%, 84.35%, and 79.64%, respectively, in dairy effluent. Taguchi method optimized the electrocoagulation parameters such as the voltage at 25V, time duration of 90min, and inter-electrode distance of 1.00cm, showcasing improved removal percentages of BOD, COD, and nitrate as 90.54%, 89.28%, and 82.74% respectively. The current study attempts to understand the optimization efficiencies between Taguchi method and response surface method for diary wastewater treatment.

Coal-based activated carbon prepared by H2O activation process for supercapacitors using response surface optimization method

Coal-based activated carbon prepared by H2O activation process for supercapacitors using response surface optimization method

Calibration and Verification of Discrete Element Parameters of Surface Soil in Camellia Oleifera Forest

To analyze the interaction between the surface soil and the soil-contacting component (65 Mn) in the camellia oleifera forest planting area in Changsha City, Hunan, China, in this study, we conducted discrete element calibration using physical and simulation tests. The chosen contact model was Hertz–Mindlin with JKR cohesion, with the soil repose angle as the response variable. The repose angle of the soil was determined to be 36.03° based on the physical tests. The significant influencing factors of the repose angle determined based on the Plackett–Burman test were the soil–soil recovery coefficient, soil–soil rolling friction coefficient, soil-65 Mn static friction coefficient, and surface energy of soil for the JKR model. A regression model for the repose angle was developed using the Box–Behnken response surface optimization method to identify the best parameter combination. The optimal parameter combination for the JKR model was determined as follows: surface energy of soil: 0.400, soil–soil rolling friction coefficient: 0.040, soil-65 Mn static friction coefficient: 0.404, and soil–soil recovery coefficient: 0.522. The calibrated discrete element parameters were validated through experiments on the repose angle and steel rod insertion. The results indicated that the relative errors obtained from the two verification methods were 2.44% and 1.71%, respectively. This research offers fundamental insights for understanding the interaction between soil and soil-contacting components and optimizing their design.

Numerical investigation and optimization of the melting performance of latent heat thermal energy storage unit strengthened by graded metal foam and mechanical rotation

In this paper, a combined passive graded metal foam and active mechanical rotation strategy is proposed to simultaneously solve the problem of slow melting rate and non-uniform phase change problem of the latent heat thermal energy storage (LHTES) technology. The enthalpy-porosity method and fixed grid structure are employed to numerically investigate the effects of porosity range, the number of graded layers, and the rotational angular velocity. Moreover, the response surface method (RSM) is further selected to optimize the structural parameters and obtain the function of melting performance and various factors. The result shows that there is an optimal porosity range and the total melting time decreases first and then increases with the increase of porosity range. When the porosity range is 12 % and the graded layer is three, it can shorten the melting time by 35.54 % and increase the thermal energy storage rate (TESR) by 51.57 %. In addition, the melting performance is gradually improved as the number of graded layers increases. The strengthening effect of graded metal foam with just four layers is close to that of the maximum layers considered in this paper. The trend of the influence of rotation speed on the melting performance of the LHTES unit is consistent with the porosity range, indicating the existence of the optimal rotational speed. The RSM optimization structure, with a 14.969 % porosity range, 5-layer graded number, and 2.267 rpm rotational speed, shortens the melting time by 42.42 % and increases the TESR by 62.75 % compared with the stationary case with uniform metal foam. This work verifies the effectiveness of active rotation coupling with passive graded porous structures, which could provide a new strengthening approach to enhance LHTES.

Optimization of pump transient energy characteristics based on response surface optimization model and computational fluid dynamics

The global energy shortage is increasingly becoming a problem of major concern worldwide. Since the pumps represent the largest part in the energy conversion devices, improving their energy characteristics is very important for energy conservation and efficiecy. However, the traditional pump design methods have generally overlooked the transient flow characteristics inside the pumps leading to high hydraulic losses and low operatinal efficiency, especially in applications that have pronounced transient effects. To address this problem, a novel approach is proposed in this paper which combines the response surface optimization method with the computational fluid dynamics (CFD) technology to optimize the energy characteristics of pumps during the transient processes. The main objective of the study is to enhance the internal flow state and the transient energy performance of the pump during the start-up process. A comparative analysis is conducted on the energy characteristics and the internal flow field of a model pump before and after the optimization, thereby validating the effectiveness of the proposed energy characteristics optimization method. The numerical results reveal that the inlet placement angle (α), the outlet placement angle (β), the blade envelope angle (φ), and the blade thickness coefficient (θ) significantly impact the weighted average head and weighted average efficiency of the pump. After optimization, the weighted average head and the weighted average efficiency of the pump increase by 2.97% and 8.91% respectively, while the transient efficiency of the pump at all times surpasses that of the traditional, non-otimized design approach. These research findings provide valuable insights for enhancing the performance of the pumps oerating in the transient flow conditions.

Temperature field analysis and cooling structure optimization of permanent magnet linear synchronous motor

A water-cooled permanent magnet linear synchronous motor was designed, and the investigation focused on the temperature distribution of motor and the optimization of the cooling structure to address its electromagnetic thermal effects. Firstly, the electromagnetic model of the motor was employed to calculate losses using finite element analysis. Subsequently, the motor's temperature distribution under various operating conditions was determined through electromagnetic-thermal coupling analysis, with prototype measurements validating the predicted outcomes. Secondly, the study placed emphasis on the impact of different water-cooled structure parameters on the motor's cooling performance, resulting in a 69 % reduction in the maximum temperature of the motor module after the cooling system was applied. Building on this, cooling structure parameters underwent optimization and design via the response surface optimization method, which achieved a reduction of 0.617 K in the motor's maximum temperature. The analysis findings revealed a substantial improvement in the motor's thrust performance by a factor of 3.08 when the water flow rate reached 1 m/s. This research can serve as a fundamental reference for the design of water cooling structures for permanent magnet linear synchronous motors.

Enrichment of Flavonoids in Short-Germinated Black Soybeans (Glycine max L.) Induced by Slight Acid Treatment.

Exogenous abiotic stimulant treatments are a straightforward and effective method for enhancing secondary metabolites in plants. In this study, the response surface optimization method was used to optimize the conditions for enriching flavonoids in short-germinated black soybeans under a slight acid treatment, and the mechanism of flavonoid accumulation during black soybean germination was explored. The results show that the use of a 126.2 mM citric acid-sodium citrate buffer (pH 5.10) as a slight acid treatment resulted in the highest flavonoid content when the black soybeans were germinated for 24 h. Under these conditions, the isoflavonoid (glycitin, daidzein, and genistein) increased significantly, and the flavonoid content reached 2.32 mg/g FW. The microacidified germination treatment significantly increased the activities and relative gene expression levels of key enzymes involved in flavonoid metabolism (4-coumarate-CoA ligase and cinnamic acid 4-hydroxylase, etc.). However, the slight acid treatment inhibited the growth of the black soybeans and caused damage to their cells. This was evidenced by significantly higher levels of malondialdehyde, superoxide anion, and hydrogen peroxide compared to the control group. Furthermore, the antioxidant system in the short-germinated soybeans was activated by the slight acid treatment, leading to a significant increase in the activities and relative gene expression levels of catalase and peroxidase. The results above show that a slight acid treatment was beneficial in inducing the accumulation of flavonoids during the growth of black soybean sprouts. This lays a technical foundation for producing black soybean products that are rich in flavonoids.

Octopus Predation-Inspired Underwater Robot Capable of Adsorption through Opening and Closing Claws

Underwater unmanned robots are an essential tool for human underwater exploration and detection and are widely employed in a variety of underwater operational settings. One of the hottest issues in this field is applying bionic notions to the creation of underwater unmanned robots by simulating fish swimming or cephalopod crawling. Using the tentacle suction cup adsorption technique during octopus’ predation as a model, underwater magnetic adsorption robots with the opening and closing claws were studied in this paper. First, the robot’s general structural design is presented. The claw mechanism is demonstrated by mimicking the octopus’s tentacle action during feeding, which primarily consists of an opening and closing claw that replicates the octopus’s tentacle and a magnetic adsorption unit that replicates the octopus’s suction cup adsorption. Then, the Kriging response surface optimization method is used to optimize the design of the claw mechanism to obtain excellent mechanical properties, and simulation software is used to verify. Finally, a robot prototype was built and its pool tests were conducted, with some experimental results presented. The experimental results show that after the robot reaches the predetermined position through pneumatic ejection and secondary propulsion launch, it can quickly open its claws within 0.11 s and apply 462.42 N adsorption force to complete the adsorption of the target.

A newly application of Organic Rankine Cycle for building energy management with cooling heating power hydrogen liquefaction generation- South Korea

This research revolves around the modeling and optimization of an innovative geothermal system powered by geothermal energy. The system incorporates a modified Organic Rankine Cycle to efficiently produce electricity, hydrogen, cooling, and heating. The study is specifically tailored for South Korea, with a focus on the city of Ulsan. The primary objective of this geothermal system is to generate essential products for residential buildings without contributing to carbon emissions or environmental pollution. The modeling aspect of this research is conducted using EES software, while optimization efforts are aimed at enhancing performance by optimizing the exergy efficiency and reducing costs. The response surface method (RSM) and Design Expert optimization software are employed for this purpose. The optimal results demonstrate that, in its most efficient state, the system can achieve an impressive exergy efficiency of 45.382 % and operate at a cost rate of 50.414 $/h. The economic analysis underscores that the modified ORC unit bears the highest system cost, amounting to 49.47 $/h. The findings reveal that the suggested geothermal system performs exceptionally well in cities with weather conditions akin to Ulsan. In other regions across the globe, it has the potential to significantly enhance cost-effectiveness and exergy efficiency. The research concludes by evaluating the system's capacity to provide electricity, heating, and cooling for residential complexes within the study areas, highlighting its potential for addressing diverse energy needs in urban settings while prioritizing sustainability and environmental responsibility. The results showed that the study system can produce 3,982,413.6 kWh of heating, and 4,555,440 kWh of cooling during the year. The environmental results showed that by producing 4088.72 MWh of electricity annually in the city of Ulsan, South Korea, it is possible to help the expansion of 4 hectares of green space per year. Also, by reducing carbon dioxide emission by 834.09 tons of CO2, the proposed system avoids the cost of 20,018.3 $ on the environment. The proposed geothermal system can supply the electrical needs of 401 people in Ulsan city during the year.

Performance of Carbon Nanotube on Nickel-Plated Copper Substrate Using Electrophoretic Deposition Process for Electronic Cooling Application: Response Surface Method Optimization

Performance of Carbon Nanotube on Nickel-Plated Copper Substrate Using Electrophoretic Deposition Process for Electronic Cooling Application: Response Surface Method Optimization

Design of an axial hydrocyclone for preliminary water separation using CFD, RSM, and SUS

Preliminary water separators can effectively solve the problem of high-water-cut produced fluids in oil wells. In this study, we propose a co-design method for the serialization of an axial inlet preliminary water separator based on the combination of cyclone separation theory, computational fluid dynamics (CFD) simulations, response surface method (RSM) optimization, experimental verification, and a scale-up strategy (SUS). For an inlet water cut ≥ 70%, the water separation rate was ≥ 50% and the oil concentration of heavy phase outlet (HPO) was ≤ 1000 mg/L. The indoor experimental results indicated that the performance of the preliminary water separator could achieve better results obtained through the CFD simulation results were taken as sample points and the optimal structural size was found by machine learning method (MLM). The field pilot test results showed that the Hy similarity criterion based SUS did not affect the separation effect. For water cut in the range of 85.0–92.7%, the water separation rate was ≥ 50% and the HPO oil concentration was < 1321.6 mg/L. Our results can provide reference and guidance for the design and optimization of hydrocyclones for preliminary water separation of oilfield produced fluids.

Study on performance optimization of double screw-magnetic fluid combination seal

The magnetic fluid seal (MFS) is a new type of sealing method that offers the advantages of no leakage and low wear. Hence, it is widely used in rotary seals in coal, chemical, and electric power fields. However, at high speeds, the degradation and even failure of the sealing performance severely limits the application of MFS in engineering. Therefore, this study designed a combined sealing device comprising a double screw seal and MFS and optimized the pressure resistance of the screw seal using an orthogonal test in combination with the response surface optimization method. Thus, the pressure resistance could be raised to 3.1 times that before optimization. The effect of the sealing gap on the sealing pressure of the MFS was analyzed by numerical simulation, and an optimal sealing gap value of 0.2 mm was obtained. The results of the verification test showed that the performance of the combined seal was significantly better than that of MFS alone. When sealing liquids, the pressure resistance of the combined seal reached 3.3 times that of the MFS at 3000 rpm, which indicates the application potential of MFS in high-speed working conditions.

Research on structural parameter optimization of a new axial inlet hydrocyclone separator based on response surface optimization method.

Aiming at the problem that the current hydrocyclone separator is affected by multiple structural parameters and there is interaction between the multiple structural parameters, it is difficult to determine the optimal structure. Taking the new axial inlet hydrocyclone separator as the research object, a fast parametric optimization method based on response surface optimization method is proposed. The overflow outlet diameter, overflow tube depth and small cone length, which have significant influence on the separation efficiency of the axial inlet hydrocyclone separator, are selected as the optimal variables, and the cyclone separation efficiency is selected as the response index. A mathematical driving model between the response index and the optimal variables is constructed by using the second-order polynomial basis function. The optimal structural parameters of the new axial inlet hydrocyclone separator are obtained through the response optimization of the parameter variables in the global response range through the mathematical driving model, and the numerical simulation method and laboratory test are double verified. The results demonstrated that the axial inlet hydrocyclone achieved the highest separation efficiency within the studied operational parameter range when the overflow pipe diameter was 6mm, the overflow pipe depth was 20mm, and the small cone length was 60mm. The separation efficiency improved from 89% to 93%. The rapid optimization of the structural parameters of the axial inlet hydrocyclone was successfully accomplished using the response surface optimization method.

Optimization design and experimental study of axial-swirling bubble generator

On the basis of the venturi tube bubble generator, a new axial swirl bubble generator is designed, and the numerical simulation of the bubble generator with different number of three baffles is carried out by using Fluent software, and it is found that the three-lobed type is significantly better than the two-leaf type and four-leaf type in the swirl velocity and core swirl area, and the response surface optimization method is used to optimize the key structure and analyze the interaction influence. The results show that the parameter that can most affect the bubble diameter is the throat diameter, followed by the expansion angle, the contraction angle has the least effect, the optimal parameters are 21.9°, the throat diameter is 5mm, and the expansion angle is 13.8°, and the accuracy of the numerical model is verified by experimental comparative analysis, and finally the influence of gas-liquid flow on bubble size is studied with the help of high-speed camera.

Investigation of Energy Loss Mechanism and Vortical Structures Characteristics of Marine Sediment Pump Based on the Response Surface Optimization Method

Marine sediment pumps are extensively applied in marine engineering fields with complex media and harsh flow conditions. Therefore, this study conducts a multi-factor optimization design for a marine sediment pump. The response surface optimization method is utilized to improve the efficiency by optimizing the number of impeller blades, the blade inlet angle, the blade outlet angle, and the blade wrap angle. Next, a response surface regression model is created, and the influence of geometric parameters on the efficiency is determined. Meanwhile, the energy loss mechanism and vortical structure characteristics after optimization are analyzed by applying entropy production and the method for identifying Omega vortices. The findings suggest a 6.33% efficiency enhancement in the optimized model under the design conditions. The impeller’s internal flow field is enhanced, and the entropy generation rate is significantly diminished. The fluid flow adhered more closely to the blade profile, and the velocity and pressure distribution exhibit better uniformity. The presence of large-scale vortices and occurrences of flow separation within the impeller passage experience a notable decrease, and the overall fluid pressure fluctuation amplitude decreased, resulting in a more stable flow. Therefore, the discoveries from the research offer references for the design and selection of marine sediment pumps.

Antioxidant Activity, Formulation, Optimization and Characterization of an Oil-in-Water Nanoemulsion Loaded with Lingonberry (Vaccinium vitis-idaea L.) Leaves Polyphenol Extract.

The active ingredients in lingonberry leaves and their beneficial properties to the human body have been well confirmed. In order to improve the stability and antioxidant activity of the active ingredients in lingonberry leaves, the response surface optimization method was used to prepare an oil-in-water nanoemulsion of polyphenol extract from lingonberry leaves. The active components in the extract were analyzed by ultra-performance liquid chromatography with triple quadrupole mass spectrometry (UPLC-TQ-MS), and bioactive compounds such as apigenin, sorbitol, and hesperidin were mainly found. Nanoemulsion droplets of 120 nm in diameter were prepared using ultrasonic emulsification. The optimal nanoemulsion formulation was determined through rigorous testing, and it was determined to be 10% (w/w) lingonberry extract and 20% (w/w) medium chain triglyceride (MCT). Additionally, a surfactant mixture was used, which combined soy protein isolate (SPI) and whey protein isolate (WPI) at 4% (w/w). The preparation method utilized ultrasonic emulsification, applying an ultrasonic power of 360 W for a duration of 300 s. The antioxidant activity (DPPH inhibition rate, ABTS inhibition rate and total reducing power) of the lingonberry nanoemulsion was significantly higher than that of the lingonberry polyphenol (LBP) extract. The nanoemulsion prepared using the optimal formulation had an entrapping efficiency of 73.25% ± 0.73% and a diameter of 114.52 ± 0.015 nm, with a satisfactory particle size of nanoscale and a PDI of 0.119 ± 0.065, demonstrating good stability of the emulsion.

Aerodynamic optimization of mixed platoon Ahmed body vehicles based on response surface method

PurposeThe purpose of this paper is to investigate the optimal average drag coefficient of the Ahmed body for mixed platoon driving under crosswind and no crosswind conditions using the response surface optimization method. This study has extraordinary implications for the planning of future intelligent transportation.Design/methodology/approachFirst, the single vehicle and vehicle platoon models are validated. Second, the configuration with the lowest average drag coefficient under the two conditions is obtained by response surface optimization. At the same time, the aerodynamic characteristics of the mixed platoon driving under different conditions are also analyzed.FindingsThe configuration with the lowest average drag coefficient under no crosswind conditions is 0.3 L for longitudinal spacing and 0.8 W for lateral spacing, with an average drag coefficient of 0.1931. The configuration with the lowest average drag coefficient under crosswind conditions is 10° for yaw angle, 0.25 L for longitudinal spacing, and 0.8 W for lateral spacing, with an average drag coefficient of 0.2251. Compared to the single vehicle, the average drag coefficients for the two conditions are reduced by 25.1% and 41.3%, respectively.Originality/valueThis paper investigates the lowest average drag coefficient for mixed platoon driving under no crosswind and crosswind conditions using a response surface optimization method. The computational fluid dynamics (CFD) results of single vehicle and vehicle platoon are compared and verified with the experimental results to ensure the reliability of this study. The research results provide theoretical reference and guidance for the planning of intelligent transportation.

Study on multi-performance optimization of basalt stone powder supplementary cementitious materials

In order to better apply basalt powder to supplementary cementitious materials (SCMs), this paper chooses the content of basalt stone powder, fly ash and slag as the influencing factors, and the 7d drying shrinkage rate, 28d drying shrinkage rate, fluidity, 7d and 28d compressive strength of mortar as the evaluation indexes of SCMs. Based on the response surface and multi-objective optimization method, the Box-Benken experimental design method was used to study the influence of the physical and chemical superposition of various factors on the properties of supplementary cementitious materials and optimize the ratio. The low-field nuclear magnetic resonance technique was used to detect the water change and porosity difference between the reference group and the optimization group at each age. The results show that the linear interaction and interaction of basalt powder, fly ash and slag have an effect on the strength, fluidity and drying shrinkage of cementitious materials. The optimal mixing ratio of basalt stone powder supplementary cementitious material is stone powder (10.8 %), fly ash (5 %) and slag (22.69 %). Under this mix ratio, the properties of basalt powder-assisted cementitious materials have been improved and close to the reference group. In the early hydration process, the physical filling effect of supplementary cementitious materials such as stone powder can better optimize the pore structure inside the slurry and the water loss is small, the strength is improved slowly, the dry shrinkage pure cement sample is similar, and the fluidity is improved. With the extension of hydration time, the water loss of the optimized group increased, and the strength and drying shrinkage increased.

Multi-indicator optimization of riveting joint forming quality of aluminum alloy sheets based on response surface test

In this paper, the effects of the interaction between punch diameter, die depth and punch speed on the quality of riveted joints are investigated using the BBD response surface test method. The results show that the mold depth has the greatest influence on the key dimensional parameters of riveted joints, followed by the punching speed, and then the punch diameter, while the punch diameter and the mold depth are the two factors with the most obvious interaction. The optimum riveted joint process parameters determined are punch diameter of 5.24 mm, die depth of 1.44 mm, and stamping speed of 5.00 mm/s. The corresponding relative errors predicted by numerical simulation and response surface optimization objective are 5.96 % for neck thickness, 3.29 % for interlocking value, and 1.37 % for bottom thickness; and the relative errors predicted by experimental results and optimization objective are 13.42 % for neck thickness, 13.42 % for interlocking value, and 1.37 % for bottom thickness. 13.42 %, interlock value is 4.23 %, and bottom thickness is 2.23 %, the model accuracy is high, and the optimization method of response surface test can effectively improve the quality of riveted joints. Through numerical simulation, the metal flow law and stress distribution during the riveting and forming process of aluminum alloy plate were analyzed, and the strength test of riveted joint was carried out, and the maximum destructive shear load of the joint was 1.8 KN, and the strength of the joint was improved, which verified the validity of the response surface optimization method.

Investigation and optimization of ultrasound-assisted process of carbon dioxide absorption into amine-based nanofluids

In this study, the effect of the simultaneous application of the nanofluids and ultrasound waves on the carbon dioxide (CO2) absorption process has been investigated in a batch system. For this purpose, the methyl diethanolamine (MDEA)-based nanofluids containing zinc oxide (ZnO) nanoparticles were prepared through a two-step procedure and used as the liquid absorbents. The absorption experiments were carried out using the pressure drop method in an isothermal reactor equipped with a high-frequency (1.7 MHz) ultrasound transducer. The effects of various factors, including the temperature, initial pressure, MDEA concentration, nanoparticle concentration, and ultrasonic power upon the absorption process, were investigated using the design-of-experiments (DOE) method. At first, a parameter screening was applied to determine the significant factors affecting the process. After removing the insignificant parameters, the process optimization was performed using the response surface method (RSM). The results indicated that the employment of high-frequency ultrasound waves had a great effect on improving the CO2 absorption rate. By using a small amount of ultrasonic power (3.9 W), the absorption rate was increased by 632%. The results of the screening revealed that among the mentioned input factors, the effects of the ultrasound power, MDEA concentration, and initial pressure on the process were significant, and the effects of the other factors were insignificant. Based upon the results, among the input factors, the ultrasonic power had the greatest impact on the CO2 absorption rate. The results also revealed that the utilization of ZnO nanoparticles in the ultrasound-assisted process of CO2 absorption, could lead to a slight reduction in the absorption rate, resulting from attenuation of the ultrasonic wave propagation in the liquid due to the presence of nanoparticles. The results of RSM optimization demonstrated that the best model to describe the process behavior was the quadratic model. A polynomial relation was also presented in terms of the factors affecting the process. Additionally, the optimal values of the input factors were determined to attain the maximum absorption rate by using RSM optimization.