Orthogonal Experimental Design Method Research Articles

Investigation of Machining Parameters for Turning Process

Manufacturing industries mainly concentrates on how to minimize the cost of the products. The process planers have to prepare the process plan of the product based on the availability of the recourses. All the information is available in the plan including inspection and delivery date of the product. Based on the recommendation of the manufacturing and inspection methods, components are produced at affordable cost. Most of the research work concentrated on selection of machining parameters using optimization techniques and also prove that the machining time / cost were minimized for the particular components / operations. In this work, tool nomenclature is to be considered for the investigation for selection of machining parameters. Work presents an experimental investigation of the influence of the three most important machining parameters of depth of cut, feed rate and spindle speed on surface roughness during turning of aluminium alloy. In this study, the design of experiment which is a powerful tool for experimental design is used to optimize the machining parameters for effective machining of the work piece. L9 orthogonal array experimental design method as well as analysis of variance (ANOVA) is used to analyse the influence of machining parameters on MRR & Machining Time. Two different grade of aluminium alloy i.e. AL 6063 & AL 6068 were machined with input parameters of depth of cut and speed. The output parameters are MRR and machining time. Based on the results empirical equations are formed and optimized results are validation .The optimal results are recommended to manufacturing industries.

Numerical analysis and process optimization of electron beam melting for superalloys

This study aims to determine the optimal parameters for the electron beam melting process by employing a modified transient three-dimensional thermal model. The validity of the thermal model is confirmed through experimental results. Moreover, the proposed method establishes mathematical relationships between the resulting molten pool temperature and process parameters. A broader range of process parameters for a new Ni–Co-based superalloy was achieved by investigating the effects of scanning velocities (10–100 mm/s), scanning radius (20–60 mm), and melting mass (1500–3100 g) on temperature at various electron beam power levels (10–30 kW). Regression models were established between scanning velocities-temperature, and scanning radius-temperature under different electron beam power levels. These models laid the foundation for real-time automatic control of molten pool temperature. Significantly, orthogonal experimental design and response surface method are employed to conduct a multi-objective optimization based on sixteen experiments and three parameters. The results of multi-objective optimization indicate that with a smelting mass of 1.5 kg, an electron beam power of 11 kW, a scanning radius of 60 mm, and a scanning velocity of 75 mm/s, the energy consumption is 34.95 kW h, and the theoretical mass loss of Ni element is 0.002 kg. The desirability is 91.2 %.

Comprehensive evaluation on deposition and heat transfer performance of the mixed tube bundle based on orthogonal experimental study

Deposition on heat exchange surfaces is an urgent problem to be solved to achieve efficient utilization of energy in thermal equipment. To mitigate deposition and the resultant heat attenuation, this work proposes a mixed tube bundle strategy of inserting attached cylinders behind the tube bundle, which can effectively meet the design requirements of high anti-deposition performance, high heat transfer efficiency, and low flow resistance. An integrated dynamic model for deposition is developed to elucidate the effect of ash particles on deposition, flow, and heat transfer characteristics. Based on the inverse distance weighting interpolation, a dynamic mesh smoothing technique is employed to simulate the evolving deposition layer on the heat transfer surface. In addition, the L16(43) orthogonal experimental design method is adopted to study the influence of the arrangement angle, diameter, and distance to the primary bundle of the attached cylinder on the overall performance, and determine the optimal scheme. The results show that deposition in the cases using the mixed tube bundle strategy has significantly decreased. The weakening effects of the attached cylinder on the deposition of small-medium particles and large-sized particles are due to the inhibition of vortex development in the gap of tube bundle and the deviation of the motion trajectory, respectively. The novel design exhibits the lowest deposition mass Mdep = 1.12 g and the best comprehensive performance PEC = 1.14 under the condition of the arrangement angle of 50°, the diameter of 10 mm, and the distance between the primary bundle of 5 mm. The obtained results can provide reference schemes and guidance for the optimization of the design of heat exchange equipment and accessory devices.

Effect of parameter optimization on the flow characteristics of venturi-self-excited oscillation mixer based on response surface model and multi-island genetic algorithm

Effect of parameter optimization on the flow characteristics of venturi-self-excited oscillation mixer based on response surface model and multi-island genetic algorithm

Effect of Floating Support Parameters on the Load-Sharing Performance of EDPGS Based on Mathematical Statistical Methods

The encased differential planetary gear system (EDPGS) allows power to be distributed among multiple output paths, enhancing efficiency and reducing weight. Uniform load distribution ensures stable system operation and prolongs service life. However, stochastic manufacturing errors leading to uneven load distribution pose challenges in engineering practice. To investigate the impact of floating support parameters on the load-sharing performance within an acceptable tolerance band, a dynamic model of the EDPGS considering time-varying meshing stiffness and random errors is established using the Monte Carlo method. This study employs the orthogonal experimental design method to analyze the effects of floating support stiffness and clearance on the load-sharing characteristics. The findings indicate that a larger sample size leads to a probability distribution of load-sharing coefficients closer to the Gaussian distribution, with minimal influence on the expectation and variance. Furthermore, this study highlights the significant influence of floating structure parameters on load-sharing characteristics in the encased stage systems compared to the differential stage. Decreasing floating support stiffness or increasing floating clearance proves beneficial in enhancing the load-sharing performance of the system.

Experimental Study on Optimizing Grouting Material Ratio for Rebar Sleeve Connections

In response to the inadequate performance reliability of existing prefabricated sleeve grouting materials, this study used an orthogonal experimental design method to prepare 16 sets of grouting materials based on C52.5 cement and ordinary river sand, with different water-cement ratios and varying amounts of additives including silica fume, defoamers, water reducers, and expansive agents. The effects of silica fume, defoamers, water reducers, expansive agent dosage, and water-cement ratio on the compressive strength, vertical expansion rate, and fluidity of the grouting material were studied. Based on the experimental results and comprehensive analysis, a formulation for high-performance grouting material with high reliability was determined, providing a greater safety margin for practical engineering applications.

Preparation and performance analysis of polyamide-based rapid repair material for asphalt pavement shallow groove

In order to effectively remedy shallow grooves on asphalt pavements, this study presents an innovative solution, termed Polyamide-based Asphalt Pavement Shallow Groove Rapid Repair Material (PA-SGRRM). This material employs polyamide 6 (PA6) as the matrix resin, in conjunction with polypropylene (PP), ethylene-vinyl acetate copolymer (EVA), and maleic anhydride-grafted polyethylene-octene copolymer (POE-g-MAH). It is manufactured through an extrusion granulation process. At the outset, a molecular dynamics approach was employed to assess the compatibility of the primary constituents and the adhesion between the matrix resin and asphalt, confirming the rationale behind the material selection. Subsequently, the orthogonal experimental design method was utilized to investigate the influence of design parameters (POE-g-MAH content, PP content, and EVA content) on the flexural strength, tensile strength, low-temperature toughness, and melt flow rate of PA-SGRRM. Following this, we prepared samples with the optimal proportions of EVA and POE-g-MAH and conducted a separate analysis to evaluate the impact of PP on the saturated moisture content of PA-SGRRM. Finally, we employed Scanning electron microscopy (SEM) to observe the microstructures of the low-temperature fracture surface and ambient temperature tensile fracture surface of the PA-SGRRM and employed Fourier transform infrared spectroscopy (FTIR) to deduce the primary chemical reactions occurring within the PA-SGRRM. The results demonstrated that POE-g-MAH played a crucial role in enhancing the compatibility of the simulated hybrid system consisting of PP and PA6. Additionally, it was observed that adhesion between PA6 and asphalt existed, with a gradual decrease as temperature rose. The content of POE-g-MAH and PP were the two primary parameters influencing the performance of PA-SGRRM. POE-g-MAH exerted a significant adverse impact on the flexural strength, tensile strength, and melt flow rate of PA-SGRRM, while substantially improving its low-temperature toughness. The PP positively reduced the water absorption characteristics of PA-SGRRM. Based on the experimental results, the optimal combination of design parameters for PA-SGRRM is recommended.

The Impact of Temperature on the Electromagnet and Structural Optimization of a Solenoid Valve

The mathematical model of the solenoid valve under varying temperatures is constructed to investigate itsperformance and enhance heat dissipation balance. The relationship between temperature and electromagnetic force isdetermined. Electrothermal coupling simulation using COMSOL is conducted, optimizing the outer diameter and lengthstructure parameters of the coil. It is established that the heat dissipation of the coil is influenced by its outer diameter.Subsequently, based on optimized coil structure parameters, an orthogonal experimental design method combinedwith Ansys Maxwell is employed for simulation solution analysis to study the impact of structural parameters such aslength, position, front and rear angles of the magnetic barrier ring in the iron core, armature length, and through-holesize on electromagnetic force. Optimal structural parameters are identified. Results indicate a decrease in steady-stateelectromagnet temperature by 3–4℃, an increase in the initial electromagnetic force by 32.63%, and a rise in the maximumelectromagnetic force by 27.10%.

Evaluation of PCM thermophysical properties on a compressed air energy storage system integrated with packed-bed latent thermal energy storage

Compressed air energy storage (CAES) is a promising large-scale energy storage technology to mitigate the fluctuations and intermittence of renewable energies. The application of latent thermal energy storage (LTES) using phase change materials (PCM) to recover compressed waste heat can further improve the energy storage density and round-trip efficiency of CAES. However, there are very few guidelines of PCM selection for a CAES system. In view of the challenge, this study first conducts orthogonal experiments to analyze the effects of the thermophysical properties of PCMs on the performance of the packed-bed LTES and CAES system. Then a PCM selection procedure for CAES is developed based on the orthogonal experiment design and TOPSIS method. The results of range analysis indicate that each thermophysical property of PCM has quite different relative importance to the performance indicators of the CAES system. From the aspect of packed-bed LTES, the density (40.8 %) and latent heat (32.8 %) of PCMs are the top two impact factors for the heat storage rate, while the melting temperature (45.7 %) and thermal conductivity (22.4 %) are the top two impact factors for the residual heat. From the aspect of the CAES system, the density (31.9 %) and melting temperature (24.4 %) are the top two impact factors for the round-trip efficiency, while the density (42.2 %) and latent heat (35.2 %) rank the top two impact factors for the air storage capacity.

Construction risk analysis of cantilever casting mid-span closure of bridge in reservoir area

In order to assess the impact of frequent microseismic and cyclic water flow forces on the bridge cantilever casting construction in the Three Gorges reservoir area, a limited element-quantum-orthogonal experimental design-neural network-Monte Carlo simulation method was used to analyze the risk assessment of the construction. The orthogonal experimental design method is utilized to generate probability distribution samples of water velocity, water height, and microseismic acceleration. These samples are then combined with a finite element model and trained using a BP neural network. This approach aims to establish a nonlinear mapping relationship between each control parameter and the axial deviation value in the mid-span closure, and then the Monte Carlo simulation is used to generate the random influence parameter, which can be substituted into the trained BP neural network to predict the risk of the error in the mid-axial deviation. The results suggested that the risk probability of the medial axis deviation of the closure section due to the coupling effect of water flow force and high-frequency microseismicity had reached 5.06%, and the risk of line deviation of the cantilever casting construction of the bridge in the reservoir area needed to be paid sufficient attention and prevented. The risk of line deviation of the cantilever casting construction of the reservoir bridge needs to attract enough attention and precaution.

Research on energy-saving strategies in the architectural design of the Eastern Railway in the era of artificial intelligence

Abstract This paper takes the air conditioning energy consumption in railroad building design as the main object of analysis and uses an orthogonal experimental design method to study the influencing factors and effects of energy consumption in the Middle East railroad construction design. Stochastic working condition simulation is carried out for the typical models of passenger stations in five climate zones to obtain the data set of the passenger station energy consumption model, and the multiple linear regression prediction models of air conditioning energy consumption in different regions are established. Combined with the hour-by-hour average outdoor temperature, hour-by-hour passenger flow and lighting and related equipment data in the waiting hall of a city in July, the air-conditioning cold load of railroad passenger stations is simulated and analyzed. Explore the implementation effect of energy-saving strategies for railroad passenger station air-conditioning system, and for the traditional PID control strategy, put forward the control strategy based on model prediction, analyze the change of centralized air-conditioning system cold load and the change of the actual performance coefficient of the chiller unit under different control strategies. The data show that compared with the traditional PID control, the model prediction control reduces the total energy consumption by 0.2063, which realizes the energy-saving optimization of the air conditioning system for railroad building design.

Improvement effect of different modifiers on storage stability of high content SBS modified asphalt

High content Styrene-butadiene-styrene (SBS) modified asphalt binder is commonly used for permeable pavements attribute to reasonable adhesion ability, deformation resistance and toughness. However, due to the large difference in molecular weight between styrene-butadiene-styrene block copolymer and asphalt, the compatibility between SBS and asphalt has always been a key issue restricting its development. To improve the compatibility of high content SBS modified asphalt, the preparation process of high content SBS modified asphalt (shear time, temperature, rate, modifier content) was investigated by orthogonal experimental design method. The effects of modifiers (polyphosphoric acid, montmorillonite, and sulfur) on the physical properties and compatibility of high content SBS modified asphalt were investigated by physical property tests, storage stability tests and dynamic shear rheology tests. The results shows that all three additives have improved the storage stability of high content SBS-modified asphalt, among which, nano montmorillonite has the best comprehensive improvement effect. In addition, the preparation process of high content SBS modified asphalt will also affect its physical properties and compatibility. When the content of MMT and SBS is 2% and 8% respectively, the shear temperature is 170 °C, the shear rate is 4000 rpm, and the shear time is 150 min, the high and low temperature performance of high content SBS modified asphalt is good and the compatibility is the best.

Effect of direct addition of asphalt rubber pellets on mixing, performance and VOCs of asphalt mixtures

Direct injection modifiers revealed vast development potential because of their convenience utilization and no need for professional equipment. However, different characteristics of each direct injection modifier fluctuate significantly on the mixing process and road performance of their modified asphalt mixtures. The purpose of this paper is to evaluate the effectiveness of two novel asphalt rubber pellets (ARP) and asphalt desulfurized rubber pellets (ADRP) in improving the performance of asphalt mixtures. Firstly, this paper used orthogonal experimental design method to determine the priority order of the influencing factors on direct injection modifiers (ARP and ADRP), and further optimized the mixing technology of asphalt mixtures containing direct injection modifiers. Then, using base asphalt, commercial asphalt rubber (AR) and SBS (styrene-butadiene-styrene block copolymer) modified asphalt as control groups, the road performance of five asphalt mixtures was evaluated. Finally, the volatile organic compounds (VOCs) release characteristics of the asphalt mixtures were quantitatively analyzed. The results indicated that the priority order of factors affecting the ARP and ADRP is digestion time > dry mixing time > mixing temperature, and the optimal mixing process parameters are dry mixing for 90 s, mixing temperature of 180 °C, and digestion time of 90 min. Additionally, road performance of ADRP modified asphalt mixtures (ADRP-AM) is superior to that of ARP modified asphalt mixture (ARP-AM), which reaches or even exceeds the road performance of asphalt rubber mixtures (AR-AM) and SBS modified asphalt mixtures (SBS-AM) prepared by wet process. The five asphalt mixtures demonstrate the similar VOCs composition, and the total concentration of VOCs emissions is ARP-AM > AR-AM > ADRP-AM > B-AM > SBS-AM. P-/m-xylene, acetone, benzene, ethylbenzene and substances containing chlorine emerge high concentration for the VOCs composition of the five asphalt mixtures. This research can provide technical support for promoting the widespread application of direct injection asphalt rubber pellets.

Impact of Built‐in Helical Fins on the Performance of Oil‐Gas Cyclone Separators

AbstractAn improved design was proposed by incorporating helical fins onto the vortex finder, and the impact on the comprehensive performance of the oil‐gas cyclone separator was analyzed based on flow field characteristics. The results revealed that the integration of helical fins led to a slight enhancement in the overall separation efficiency and a significant reduction in pressure drop, thus contributing to the decrease of energy consumption in industrial processes. The orthogonal experimental design (OED) method was utilized for the discussion and optimization of five structural parameters related to the helical fins. This study provides new insights for the design of internal components of oil‐gas separators.

Study on Proportioning Scheme of Coal System Rocky Similar Material Based on Orthogonal Test.

Similar materials play an important role in model testing. In order to meet the demand for similar materials in modeling tests, such as those on coal mining, coal system rocky similar materials were formulated using yellow sand as a coarse aggregate, heavy calcium carbonate as a fine aggregate, and cement and gypsum as binders. Based on the orthogonal experimental design method, four influencing factors, namely the aggregate-binder ratio, heavy calcium carbonate content, cement-gypsum ratio, and moisture content, were selected. Each factor was designed at five levels. Through weighing, uniaxial compression, Brazilian splitting, and variable-angle plate shear tests on 225 specimens under 25 different ratios, five physico-mechanical property indicators of the material, including density, compressive strength, tensile strength, cohesion, and internal friction angle, were obtained under different ratios. The test results indicate that the similar materials formulated with the above raw materials had a wide range of mechanical properties, which met the simulation needs of different types of coal rocks, such as main coking coal, anthracite, shale, etc., in the similar model test. Range analysis was adopted to analyze the sensitivities to each factor, which showed that the density and internal friction angle of similar materials are mainly controlled by the aggregate-binder ratio; the cement-gypsum ratio mainly controls the compressive strength, tensile strength, and cohesion of the material. Analysis of variance (ANOVA) was adopted to analyze the sensitivities to each factor, which showed that the aggregate-binder ratio had a highly significant effect on the density of the material, the cement-gypsum ratio had a highly significant effect on the compressive and tensile strength of the material, the cement-gypsum ratio had a significant effect on the cohesion and density of the material, and the moisture content had a significant effect on the compressive strength of the material. The remaining factors did not significantly affect the material parameters. The results of this study can provide some reference for the selection of coal system rocky similar materials in subsequent physical modeling tests.

Research on Microclimate-Suitable Spatial Patterns of Waterfront Settlements in Summer: A Case Study of the Nan Lake Area in Wuhan, China

As China’s urbanization progresses, thermal environmental problems such as the overheating effect experienced by cities are becoming more and more obvious in the daily lives of residents. Urban waterfront spaces not only create pleasant landscape environments and regulate microclimates, but also help to maintain ecological diversity. However, the current high-density urban construction model has led to poor air mobility and weakened water regulation functions in cities. Therefore, the rationalization of the spatial form of settlements has become particularly important in recent times. In this study, the Nan Lake area of Wuhan City was taken as the research object, and it was simulated using ENVI-met (5.5.1) software. Further, the orthogonal experimental design method was combined with the extremum difference analysis method. This study focused on the effects of the layout form (LF), floor area ratio (FAR), green form (GF), and offshore distance (OD) on the temperature (T), relative humidity (RH), and thermal comfort in waterfront settlements in summer. This study found that (1) among the various factors, the effect of the GFs and LFs on the overall microclimate of the study region was the most significant, while the volume ratio had the least significant effect on each indicator. (2) The parallel layout form was found to have better ventilation effects compared to the other three layout forms, with its cooling and humidifying effects being superior. (3) Among the four types of greening combinations, the combination of “grass + shrubs” had the best cooling effect at the height of pedestrians, while trees were able to reduce the heat transfer of solar radiation to the ground due to the shading and evaporation effects provided by their canopies. (4) The cooling and humidifying effects provided by the water body of Nan Lake gradually diminished as the distance from its shore increased; therefore, waterfront settlements maintaining a reasonable proximity to their water bodies will help bring into play the microclimate adjustment effect of such bodies. This study provides a valuable reference for the construction and renewal of urban waterfront settlements in the hot summer and cold winter zones of China (HSCW).

Optimal design of impeller for self-priming pump based on orthogonal method

In order to improve the efficiency of the self-priming pump in the outdoor emergency rescue mobile pump truck, this paper took the key energy conversion component-impeller as the target and used the orthogonal experimental design method to optimize its hydraulic performance. Firstly the numerical calculations were compared with the experimental results to confirm the reliability of the calculation method. Then, L9 (34) orthogonal design was applied to investigate the influence of the impeller diameter, the blade outlet width, the blade wrap angle and the number of blades on the hydraulic performance of the self-priming pump. Through range analysis, the order of influence of each influencing factor on the head and efficiency of the self-priming pump was determined, and finally obtained the optimal parameter combination scheme. The results show that the optimized self-priming pump exceeds the head of the prototype pump at all flow conditions, and the efficiency curve at high flow conditions is significantly improved and has a wide high efficiency zone.

Significance analysis of the factors influencing the strength of the frozen soil-structure interface and their interactions in different phase transition zones

The freezing strength of the contact interface between foundation soil and infrastructure has been a key and difficult problem in the study of frost jacking of piles in cold regions; previous studies have focused on the influence law of experimental factors on freezing strength, and there are few studies on the significance of the effects of factors and their interactions on the freezing strength in different phase transition zones. In this paper, based on the existing test data, the orthogonal experimental design method considering the interactions, the principles of range analysis and variance analysis were used to investigate the significance of the effects of factors influencing the freezing strength in different phase transition zones and their interactions. Finally, a new method for establishing the prediction model of freezing strength based on the multiple linear regression model was proposed. The research shows that there are significant differences in the effects of the experimental factors and their interactions on the freezing strength in different phase transition zones. The freezing strength prediction model established by the new method can better reflect the variation law of freezing strength with factors in different phase transition zones and the influence degree of the interactions between factors.

Fuel Consumption Rate Optimization Analysis of Dual-fuel Marine Diesel Engines Based on Orthogonal Design

To investigate the influence of diesel engine operating matching parameters on the comprehensive fuel consumption rate of butanol-diesel dual-fuel engines, a high-pressure combustion chamber cycle model of a 4190ZLC-2 marine medium-speed diesel engine was established using AVL-FIRE simulation software. After establishing the optimum blending ratio of butanol, the fuel system parameters were optimized using a one-time regression orthogonal experimental design method, and a mathematical model for fuel consumption rate prediction was constructed to find the combination of parameters with the lowest fuel consumption rate as the target. The study shows that inlet pressure has the greatest influence on the fuel consumption rate, followed by EGR and inlet air temperature. The lowest fuel consumption rate was achieved by combining the following parameters: (butanol blending ratio of 20%, EGR rate 0, inlet pressure 0.233 MPa, inlet temperature 325.15 K, Injection advance angle 22.6 °CA, the diameter of oil injection hole (0.26 mm); after optimization, the fuel consumption rate was reduced by 9.96% compared to the original machine.

Effects of drip irrigation on yield, soil fertility and soil enzyme activity of different potato varieties in Northwest China.

The effects of different irrigation and fertilization on potato yield, soil fertility and soil enzyme activity of different varieties under drip irrigation fertilization mode were studied, which could provide support for selecting the best varieties in Northwest China. Three factors and three levels orthogonal experimental design method, a total of nine treatments. The three irrigation levels were W1 (100% crop evapotranspiration (ETC)), W2 (80% ETC) and W3 (60% ETC). The three fertilization levels were F1 (N-P2O5-K2O, 240-120-300 kg ha-1), F2 (180-90-225 kg ha-1) and F3 (120-60-150 kg ha-1). The three varieties were V1 (Feiuritar), V2 (Longshu7) and V3 (Qingshu 9). The results showed that different irrigation and fertilization had significant effects on potato yield, soil fertility and soil enzyme activity in root zone. The highest yield of T5 (80%ETC, 180-90-225 kg ha-1, Qingshu 9) was 49,222.3 kg ha-1. With the increase of fertilizer application rate, potato yield and soil enzyme activity in root zone increased first and then decreased, but soil electrical conductivity (SEC), soil nitrate-N content (SNNC), soil alkali-hydrolyzable nitrogen content (SAHC), soil available potassium (AK), soil available phosphorus (AP), soil ammonium-N content (SANC) and soil organic matter (SOM) in root zone increased continuously. The yield, soil catalase activity, soil urease activity and soil sucrase activity at W2 were 2.81% and 22.2%, 1.84% and 7.04%, 8.26% and 9.62%, 5.34% and 13.36% higher than those at W1 and W3, respectively. The overall trend of soil water content, soil nutrient content and enzyme activity in root zone was 0-20 cm >20-40 cm >40-60 cm soil layer. There were many soil factors affecting tuber yield, among which soil enzyme activity, pH value and root zone conductivity were the key factors. The results showed that T5 (80%ETC, 180-90-225 kg ha-1, Qingshu 9) was the best treatment to improve soil enzyme activity and yield.