Proton exchange membrane water electrolysis (PEMWE) has garnered significant attention as apivotal technology for converting surplus electricity into hydrogen for long-term storage, as well asfor providing high-purity...Proton exchange membrane water electrolysis (PEMWE) has garnered significant attention as apivotal technology for converting surplus electricity into hydrogen for long-term storage, as well asfor providing high-purity hydrogen for aerospace and high-end manufacturing applications. Withthe ongoing commercialization of PEMWE, advancing iridium-based oxygen evolution reaction(OER) catalysts remains imperative to reconcile stringent requirements for high activity, extendedlongevity, and minimized noble metal loading. The review provides a systematic analysis of theintegrated design of iridium-based catalysts in PEMWE, starting from the fundamentals of OER,including the operation environment of OER catalysts, catalytic performance evaluation withinPEMWE, as well as catalytic and dissolution mechanisms. Subsequently, the catalyst classificationand preparation/characterization techniques are summarized with the focus on the dynamic structure-property relationship. Guided by these understandings, an overview of the design strategiesfor performance enhancement is presented. Specifically, we construct a mathematical frameworkfor cost-performance optimization to offer quantitative guidance for catalyst design. Finally, futureperspectives are proposed, aiming to establish a theoretical framework for rational catalyst design.展开更多
Die casting process is one of the prime options for m anufacturing precisely dimensioned, sharply defined metal parts. The design of d ie casting dies comprises several stages and entails a large amount of time. Tra d...Die casting process is one of the prime options for m anufacturing precisely dimensioned, sharply defined metal parts. The design of d ie casting dies comprises several stages and entails a large amount of time. Tra ditionally, the different stages of the die design were not integrated but exist as separate entities. Moreover, recurring modifications or even redesigns are r equired due to the complexity in achieving an accurate initial die design. As a result, die design is usually time-consuming and costly with respect to resourc es. The die casting industry will greatly benefit if proper application software are developed that integrates the different die design stages and allows editin g of die design as and when needed. Hence it is imperative to create an integrat ed die design system that shortens the die design time. This paper presents a research that establishes a prototype of an integrated die design system. It is developed using the commercial SolidWorks CAD system and n amed DiWorks. The aim of building the system on a commercial CAD system is to ut ilise the resources and features of the CAD system to speed up the die design pr ocess. DiWorks consists of six distinct modules: Project Manager, Cavity Insert Builder, Gating System Constructor, Die Base Designer, Ejector System Constructo r and Standard Components Library. Through these six modules, the die designer c an create a complete die casting die beginning from a product part model. It is a user-friendly system that allows both experienced and novice die designers to easily accomplish the task of die design. The practical goal of this research is twofold: to develop a system that integra tes the die design process and at the same time facilitates the editing of d ie design during or after the course of the design process. The research approac h includes (i) parametric design, (ii) feature-based design (iii) system modeli ng and implementation. Parametric design deals with variable dimensions as contr ol parameters, and it is an efficient tool for creating models based on paramete rs. Parametric design not only increases the design efficiency, but also makes t he updates and modifications of existing designs easier and faster, since these can be achieved by changing the parameters of the parametric model. Feature-bas ed design is used to design a product with features that are functionally define d by attributes and are geometrically represented by a set of parameters. The re sults of this research will aid the automation of the die design process, thus i mproving the efficiency and quality of, and reducing the cost of die design.展开更多
The Next Generation Subsea Production System(NextGen SPS)is an innovative concept for petroleum development in ultra-deep water areas,mainly consisting of artificial seabed(AS),rigid ris-ers,flexible jumpers and moori...The Next Generation Subsea Production System(NextGen SPS)is an innovative concept for petroleum development in ultra-deep water areas,mainly consisting of artificial seabed(AS),rigid ris-ers,flexible jumpers and mooring lines.To improve the overall performance and design efficiency of NextGen SPS,an integrated design approach for the NextGen SPS based on multidisciplinary design optimization(MDO)method was investigated in this paper by combing the multidisciplinary feasible(MDF)architecture and particle swarm optimization(PSO)algorithm to establish the design frame-work.Two sub-disciplines of hydrodynamic analysis and global performance analysis were defined,and analysis method in each sub-discipline was introduced.Surrogate models of hydrodynamic analy-sis and global performance analysis were developed by using Latin hypercube sampling method and back propagation neural network(BPNN).Surrogate models were incorporated into the design frame-work,through which an integrated design for NextGen SPS at a depth of 3000 m was implemented.It is concluded that both the overall performance and the design efficiency of NextGen SPS are improved.展开更多
The purpose of this study is to contribute methodologically, through a systematic study of the application of different optimization techniques to design integrated distillation columns in binary, for it established o...The purpose of this study is to contribute methodologically, through a systematic study of the application of different optimization techniques to design integrated distillation columns in binary, for it established one optimization technique, deterministic, was optimized distillation column at steady state. For this part was used tabu search to solve the type binary problem. For each choice of the search whole continuous variables were optimized with the deterministic method for process design perturbation is applied to the molar fraction of the feed. It develops and implements the mathematical algorithm solving the problem, then validation of the methodology proposed dynamic simulation of the system is compared with and without control, with both traditional and integrated approaches.展开更多
In this paper, sensitivity approaches are taken to analyze and design an integrated flight propulsion control system where the interaction between subsystems direitly affects the stability property and handling perfor...In this paper, sensitivity approaches are taken to analyze and design an integrated flight propulsion control system where the interaction between subsystems direitly affects the stability property and handling performances of the aircraft. The eigenvalue sen sitivity approach is employed to study the effect of coupling parameters on system stability and gain sensitivity approach is used to direct the reduced states feedback suboptimal control system design. Simulation results show that the integrated flight propulsion control system designed by sensitivity approaches is of good performance.展开更多
According to the operational characteristics of the logistics networks for the third party logistics supplier （3PLS）, the forward and reverse logistics networks together for 3PLS under the uncertain environment are ...According to the operational characteristics of the logistics networks for the third party logistics supplier （3PLS）, the forward and reverse logistics networks together for 3PLS under the uncertain environment are designed. First, a fuzzy model is proposed by taking multiple customers, multiple commodities, capacitated facility location and integrated logistics facility layout into account. In the model, the fuzzy customer demands and transportation rates are illustrated by triangular fuzzy numbers. Secondly, the fuzzy model is converted into a crisp model by applying fuzzy chance constrained theory and possibility theory, and one hybrid genetic algorithm is designed for the crisp model. Finally, two different examples are designed to illustrate that the model and solution discussed are valid.展开更多
In the design process of advanced aero-engines,it is necessary to carry out an effective analysis method between structural features and mechanical characteristics for a better structural optimization.Based on the str...In the design process of advanced aero-engines,it is necessary to carry out an effective analysis method between structural features and mechanical characteristics for a better structural optimization.Based on the structural composition and functions of aero-engines,the concept and contents of structural efficiency can reflect the relation between structural features and mechanical characteristics.In order to achieve the integrated design of structural and mechanical characteristics,one quantitative analysis method called Structural Efficiency Assessment Method(SEAM)was put forward.The structural efficiency coefficient was obtained by synthesizing the parameters to quantitatively evaluate the aero-engine structure design level.Parameterization method to evaluate structural design quality was realized.After analyzing the structural features of an actual dual-rotor system in typical high bypass ratio turbofan engines,the mechanical characteristics and structural efficiency coefficient were calculated.Structural efficiency coefficient of high-pressure rotor(0.43)is higher than that of low-pressure rotor(0.29),which directly shows the performance of the former is better,there is room for improvement in structural design of the low-pressure rotor.Thus the direction of structural optimization was pointed out.The applications of SEAM shows that the method is operational and effective in the evaluation and improvement of structural design.展开更多
Inspired by the three-dimensional design of flow passages in turbomachinery,this study proposes the concept of integrated passage design.The capability of adjoint method for efficient optimization and the flexibility ...Inspired by the three-dimensional design of flow passages in turbomachinery,this study proposes the concept of integrated passage design.The capability of adjoint method for efficient optimization and the flexibility of the parameterization method based on extended free-form defor-mation have been considered to develop a feasible approach to design an integrated passage.This concept was applied to redesign a typical transonic fan,Rotor 67,and the results were analyzed by CFX.It is shown that the passage was adequately adjusted in all three dimensions and reduced the strength of shock wave and wake-induced flow.In particular,the secondary flow was appropriately reorganized and the corner separation was well controlled in the end wall region,leading to signif-icant improvements in adiabatic efficiency and diffusion.展开更多
According to the variable toe-to-heel well spacing, combined with the dislocation theory, discrete lattice method, and finite-element-method(FEM) based fluid-solid coupling, an integrated geological-engineering method...According to the variable toe-to-heel well spacing, combined with the dislocation theory, discrete lattice method, and finite-element-method(FEM) based fluid-solid coupling, an integrated geological-engineering method of volume fracturing for fan-shaped well pattern is proposed considering the geomechanical modeling, induced stress calculation, hydraulic fracturing simulation, and post-frac productivity evaluation. Besides, we propose the differential fracturing design for the conventional productivity-area and the potential production area for fan-shaped horizontal wells. After the fracturing of the conventional production area for H1 fan-shaped well platform, the research shows that the maximum reduction of the horizontal principal stress difference in the potential productivity-area is 0.2 MPa, which cannot cause the stress reversal, but this reduction is still conducive to the lateral propagation of hydraulic fractures. According to the optimized fracturing design, in zone-Ⅰ of the potential production area, only Well 2 is fractured, with a cluster spacing of 30 m and an injection rate of 12 m^(3)/min per stage;in zone-Ⅱ, Well 2 is fractured before Well 3, with a cluster spacing of 30 m and an injection rate of 12 m^(3)/min per stage. The swept area of the pore pressure drop in the potential production area is small, showing that the reservoir is not well developed. The hydraulic fracturing in the toe area can be improved by, for example, properly densifying the fractures and adjusting the fracture distribution, in order to enhance the swept volume and increase the reservoir utilization.展开更多
The inner rotors of distributed propulsion tilt-wing Unmanned Aerial Vehicles(UAVs)are often folded in the cruising state and deployed in vertical take-off and landing to cope with the huge difference in thrust requir...The inner rotors of distributed propulsion tilt-wing Unmanned Aerial Vehicles(UAVs)are often folded in the cruising state and deployed in vertical take-off and landing to cope with the huge difference in thrust requirements.However,the blades of the conventional rotor have poor conformality with the nacelle profile,which will greatly increase the drag of the UAV after folding.This paper proposes an integrated method for the design of rotor and nacelle considering geometric compatibility to reduce the drag of the folded rotor and nacelle,so as to further improve the aerodynamic efficiency in cruise while ensuring the rotor efficiency in the vertical flight mode.A geometric mapping model based on nacelle design parameters and rotor design parameters is established,and a parametric model and aerodynamic optimization model of the outer arc airfoil family are developed.In addition,a rotor performance analysis model and a neural network response surface model for nacelle drag prediction that meet the requirements of confidence level are established.Based on the oblique inflow blade element momentum theory method,numerical simulation method,and genetic algorithm,an integrated optimization framework of the design of the conformal rotor and nacelle is built.Then,a geometrically compatible integrated optimization for the rotor and nacelle is carried out with the objective of maximizing energy efficiency in the full mission profile.Finally,a conformal rotor and nacelle design solution is obtained,which satisfies geometric compatibility and thrust constraints while providing high thrust efficiency and low cruising drag.A comparison of the results of the integrated design and the conventional rotor optimization design shows that the drag of the conventional rotor is 3.45 times that of the conformal integrated design in the cruising state,which proves the effectiveness and necessity of the proposed method.展开更多
This paper creates 3D solid model and assembly of U RJ 92-6 oil tank and analyses its strength by integrated CAD/CAE/CAM software I-D EAS. Through integrated simulation in computer, design efficiency and quality of oi...This paper creates 3D solid model and assembly of U RJ 92-6 oil tank and analyses its strength by integrated CAD/CAE/CAM software I-D EAS. Through integrated simulation in computer, design efficiency and quality of oil tank is greatly improved. Adopting integrated CAD/CAE/CAM software to carry out integrated research to equ ipment and products, we will be able to take overall analysis in aspects of 3-D solid modeling, pre-assembly and strength, etc., to realize non-paper designi ng and parallel designing. Problems can be found and settled during designing, w hich will increase designing efficiency and one-time success rate and realize o ptimum designing for products.展开更多
An integration system was developed to satisfy the need of information integration in the process of designing, investment casting and monitoring aero-engine's turbo blade. The general architecture is detailed pre...An integration system was developed to satisfy the need of information integration in the process of designing, investment casting and monitoring aero-engine's turbo blade. The general architecture is detailed presented in this paper. The system mainly comprises of product master model, design information management, anti-deformation design of mould cavity, intelligence mould design and blade testing. The developed system can manage mould design and blade test data flow, optimize mould design process and achieve the goal of integration design.展开更多
The integrated layout problem in manufacturing Systems is investigated. Anintegrated model for Concurrent layout design of cells and flow paths is formulated. A hybridapproach combined an enhanced branch-and-bound alg...The integrated layout problem in manufacturing Systems is investigated. Anintegrated model for Concurrent layout design of cells and flow paths is formulated. A hybridapproach combined an enhanced branch-and-bound algorithm with a simulated annealing scheme isproposed to solve this problem. The integrated layout method is applied to re-layout the gear pumpshop of a medium-size manufacturer of hydraulic pieces. Results show that the proposed layout methodcan concurrently provide good solutions of the cell layouts and the flow path layouts.展开更多
The aerodynamic performance, structural strength, and wheel weight are three important factors in the design process of the radial turbine for micro gas turbines. This study presents the experimental validation proces...The aerodynamic performance, structural strength, and wheel weight are three important factors in the design process of the radial turbine for micro gas turbines. This study presents the experimental validation process of this integrated optimization design method by using the similarity theory. Cold modeling tests and investigations into the aerodynamic characteristics were performed. Experimental results showed that the aerodynamic efficiency of the micro radial turbine is 84.3% at the design point while also satisfying the aerodynamic and strength requirements. Meanwhile, the total weight of the turbine wheel is 3.8 kg which has only a 52.8% mass of the original design. This indicates that the radial turbine designed through this technique has a high aerodynamic performance, and thus can be applied to micro gas turbines. The results validated that this integrated optimization design method is reliable.展开更多
An analytical model for current-voltage behavior of amorphous In-Ga-Zn-O thin-film transistors（a-IGZO TFTs）with dual-gate structures is developed.The unified expressions for synchronous and asynchronous operating mo...An analytical model for current-voltage behavior of amorphous In-Ga-Zn-O thin-film transistors（a-IGZO TFTs）with dual-gate structures is developed.The unified expressions for synchronous and asynchronous operating modes are derived on the basis of channel charges,which are controlled by gate voltage.It is proven that the threshold voltage of asynchronous dual-gate IGZO TFTs is adjusted in proportion to the ratio of top insulating capacitance to the bottom insulating capacitance（C_（TI）/C_（BI））.Incorporating the proposed model with Verilog-A,a touch-sensing circuit using dual-gate structure is investigated by SPICE simulations.Comparison shows that the touch sensitivity is increased by the dual-gate IGZO TFT structure.展开更多
This study integrated instrumental and relational approaches to the teaching and learning of solids in a preservice teacher＇s class. The researcher guided the preservice teachers to gather various prisms, pyramids, a...This study integrated instrumental and relational approaches to the teaching and learning of solids in a preservice teacher＇s class. The researcher guided the preservice teachers to gather various prisms, pyramids, and spheres to study the total surface areas and volumes. At the end of the integrated models, the test scores showed closed relationships in the concurrent instructional strategies of the integrated models. The researcher therefore, recommended the design models for the teaching and learning of solids in mathematics.展开更多
This paper describes how database information and electronic 3D models are integrated to produce power plant designs more efficiently and accurately. Engineering CAD/CAE systems have evolved from strictly 3D modeling ...This paper describes how database information and electronic 3D models are integrated to produce power plant designs more efficiently and accurately. Engineering CAD/CAE systems have evolved from strictly 3D modeling to spatial data management tools. This paper describes how process data, commodities, and location data are disseminated to the various project team members through a central integrated database. The database and 3D model also provide a cache of information that is valuable to the constructor, and operations and maintenance Personnel.展开更多
The overall teaching design for the junior middle school English unit aims to maximize the use of teaching resources by using the unit as the central theme,integrating it throughout all sections and related activities...The overall teaching design for the junior middle school English unit aims to maximize the use of teaching resources by using the unit as the central theme,integrating it throughout all sections and related activities.This approach continually reinforces students’understanding and retention of individual lesson content while fostering their core literacy and skills.It promotes a comprehensive development of students’listening,speaking,reading,and writing skills,allowing them to engage repeatedly with the language materials until they internalize them as part of their language proficiency.展开更多
文摘Proton exchange membrane water electrolysis (PEMWE) has garnered significant attention as apivotal technology for converting surplus electricity into hydrogen for long-term storage, as well asfor providing high-purity hydrogen for aerospace and high-end manufacturing applications. Withthe ongoing commercialization of PEMWE, advancing iridium-based oxygen evolution reaction(OER) catalysts remains imperative to reconcile stringent requirements for high activity, extendedlongevity, and minimized noble metal loading. The review provides a systematic analysis of theintegrated design of iridium-based catalysts in PEMWE, starting from the fundamentals of OER,including the operation environment of OER catalysts, catalytic performance evaluation withinPEMWE, as well as catalytic and dissolution mechanisms. Subsequently, the catalyst classificationand preparation/characterization techniques are summarized with the focus on the dynamic structure-property relationship. Guided by these understandings, an overview of the design strategiesfor performance enhancement is presented. Specifically, we construct a mathematical frameworkfor cost-performance optimization to offer quantitative guidance for catalyst design. Finally, futureperspectives are proposed, aiming to establish a theoretical framework for rational catalyst design.
文摘Die casting process is one of the prime options for m anufacturing precisely dimensioned, sharply defined metal parts. The design of d ie casting dies comprises several stages and entails a large amount of time. Tra ditionally, the different stages of the die design were not integrated but exist as separate entities. Moreover, recurring modifications or even redesigns are r equired due to the complexity in achieving an accurate initial die design. As a result, die design is usually time-consuming and costly with respect to resourc es. The die casting industry will greatly benefit if proper application software are developed that integrates the different die design stages and allows editin g of die design as and when needed. Hence it is imperative to create an integrat ed die design system that shortens the die design time. This paper presents a research that establishes a prototype of an integrated die design system. It is developed using the commercial SolidWorks CAD system and n amed DiWorks. The aim of building the system on a commercial CAD system is to ut ilise the resources and features of the CAD system to speed up the die design pr ocess. DiWorks consists of six distinct modules: Project Manager, Cavity Insert Builder, Gating System Constructor, Die Base Designer, Ejector System Constructo r and Standard Components Library. Through these six modules, the die designer c an create a complete die casting die beginning from a product part model. It is a user-friendly system that allows both experienced and novice die designers to easily accomplish the task of die design. The practical goal of this research is twofold: to develop a system that integra tes the die design process and at the same time facilitates the editing of d ie design during or after the course of the design process. The research approac h includes (i) parametric design, (ii) feature-based design (iii) system modeli ng and implementation. Parametric design deals with variable dimensions as contr ol parameters, and it is an efficient tool for creating models based on paramete rs. Parametric design not only increases the design efficiency, but also makes t he updates and modifications of existing designs easier and faster, since these can be achieved by changing the parameters of the parametric model. Feature-bas ed design is used to design a product with features that are functionally define d by attributes and are geometrically represented by a set of parameters. The re sults of this research will aid the automation of the die design process, thus i mproving the efficiency and quality of, and reducing the cost of die design.
文摘The Next Generation Subsea Production System(NextGen SPS)is an innovative concept for petroleum development in ultra-deep water areas,mainly consisting of artificial seabed(AS),rigid ris-ers,flexible jumpers and mooring lines.To improve the overall performance and design efficiency of NextGen SPS,an integrated design approach for the NextGen SPS based on multidisciplinary design optimization(MDO)method was investigated in this paper by combing the multidisciplinary feasible(MDF)architecture and particle swarm optimization(PSO)algorithm to establish the design frame-work.Two sub-disciplines of hydrodynamic analysis and global performance analysis were defined,and analysis method in each sub-discipline was introduced.Surrogate models of hydrodynamic analy-sis and global performance analysis were developed by using Latin hypercube sampling method and back propagation neural network(BPNN).Surrogate models were incorporated into the design frame-work,through which an integrated design for NextGen SPS at a depth of 3000 m was implemented.It is concluded that both the overall performance and the design efficiency of NextGen SPS are improved.
文摘The purpose of this study is to contribute methodologically, through a systematic study of the application of different optimization techniques to design integrated distillation columns in binary, for it established one optimization technique, deterministic, was optimized distillation column at steady state. For this part was used tabu search to solve the type binary problem. For each choice of the search whole continuous variables were optimized with the deterministic method for process design perturbation is applied to the molar fraction of the feed. It develops and implements the mathematical algorithm solving the problem, then validation of the methodology proposed dynamic simulation of the system is compared with and without control, with both traditional and integrated approaches.
文摘In this paper, sensitivity approaches are taken to analyze and design an integrated flight propulsion control system where the interaction between subsystems direitly affects the stability property and handling performances of the aircraft. The eigenvalue sen sitivity approach is employed to study the effect of coupling parameters on system stability and gain sensitivity approach is used to direct the reduced states feedback suboptimal control system design. Simulation results show that the integrated flight propulsion control system designed by sensitivity approaches is of good performance.
文摘According to the operational characteristics of the logistics networks for the third party logistics supplier （3PLS）, the forward and reverse logistics networks together for 3PLS under the uncertain environment are designed. First, a fuzzy model is proposed by taking multiple customers, multiple commodities, capacitated facility location and integrated logistics facility layout into account. In the model, the fuzzy customer demands and transportation rates are illustrated by triangular fuzzy numbers. Secondly, the fuzzy model is converted into a crisp model by applying fuzzy chance constrained theory and possibility theory, and one hybrid genetic algorithm is designed for the crisp model. Finally, two different examples are designed to illustrate that the model and solution discussed are valid.
基金AECC Commercial Aircraft Engine Co.,LTD for providing the financial support。
文摘In the design process of advanced aero-engines,it is necessary to carry out an effective analysis method between structural features and mechanical characteristics for a better structural optimization.Based on the structural composition and functions of aero-engines,the concept and contents of structural efficiency can reflect the relation between structural features and mechanical characteristics.In order to achieve the integrated design of structural and mechanical characteristics,one quantitative analysis method called Structural Efficiency Assessment Method(SEAM)was put forward.The structural efficiency coefficient was obtained by synthesizing the parameters to quantitatively evaluate the aero-engine structure design level.Parameterization method to evaluate structural design quality was realized.After analyzing the structural features of an actual dual-rotor system in typical high bypass ratio turbofan engines,the mechanical characteristics and structural efficiency coefficient were calculated.Structural efficiency coefficient of high-pressure rotor(0.43)is higher than that of low-pressure rotor(0.29),which directly shows the performance of the former is better,there is room for improvement in structural design of the low-pressure rotor.Thus the direction of structural optimization was pointed out.The applications of SEAM shows that the method is operational and effective in the evaluation and improvement of structural design.
基金supported by the National Science and Technology Major Project of China(Nos.2017-II-0006-0020,J2019-II-0003-0023).
文摘Inspired by the three-dimensional design of flow passages in turbomachinery,this study proposes the concept of integrated passage design.The capability of adjoint method for efficient optimization and the flexibility of the parameterization method based on extended free-form defor-mation have been considered to develop a feasible approach to design an integrated passage.This concept was applied to redesign a typical transonic fan,Rotor 67,and the results were analyzed by CFX.It is shown that the passage was adequately adjusted in all three dimensions and reduced the strength of shock wave and wake-induced flow.In particular,the secondary flow was appropriately reorganized and the corner separation was well controlled in the end wall region,leading to signif-icant improvements in adiabatic efficiency and diffusion.
基金Supported by National Natural Science Foundation of China (52104029,U2139204)PetroChina Science and Technology Innovation Foundation (2021 DQ02-0501)。
文摘According to the variable toe-to-heel well spacing, combined with the dislocation theory, discrete lattice method, and finite-element-method(FEM) based fluid-solid coupling, an integrated geological-engineering method of volume fracturing for fan-shaped well pattern is proposed considering the geomechanical modeling, induced stress calculation, hydraulic fracturing simulation, and post-frac productivity evaluation. Besides, we propose the differential fracturing design for the conventional productivity-area and the potential production area for fan-shaped horizontal wells. After the fracturing of the conventional production area for H1 fan-shaped well platform, the research shows that the maximum reduction of the horizontal principal stress difference in the potential productivity-area is 0.2 MPa, which cannot cause the stress reversal, but this reduction is still conducive to the lateral propagation of hydraulic fractures. According to the optimized fracturing design, in zone-Ⅰ of the potential production area, only Well 2 is fractured, with a cluster spacing of 30 m and an injection rate of 12 m^(3)/min per stage;in zone-Ⅱ, Well 2 is fractured before Well 3, with a cluster spacing of 30 m and an injection rate of 12 m^(3)/min per stage. The swept area of the pore pressure drop in the potential production area is small, showing that the reservoir is not well developed. The hydraulic fracturing in the toe area can be improved by, for example, properly densifying the fractures and adjusting the fracture distribution, in order to enhance the swept volume and increase the reservoir utilization.
基金the Fundamental Research Funds for the Central Universities(No.56XCA2205402).
文摘The inner rotors of distributed propulsion tilt-wing Unmanned Aerial Vehicles(UAVs)are often folded in the cruising state and deployed in vertical take-off and landing to cope with the huge difference in thrust requirements.However,the blades of the conventional rotor have poor conformality with the nacelle profile,which will greatly increase the drag of the UAV after folding.This paper proposes an integrated method for the design of rotor and nacelle considering geometric compatibility to reduce the drag of the folded rotor and nacelle,so as to further improve the aerodynamic efficiency in cruise while ensuring the rotor efficiency in the vertical flight mode.A geometric mapping model based on nacelle design parameters and rotor design parameters is established,and a parametric model and aerodynamic optimization model of the outer arc airfoil family are developed.In addition,a rotor performance analysis model and a neural network response surface model for nacelle drag prediction that meet the requirements of confidence level are established.Based on the oblique inflow blade element momentum theory method,numerical simulation method,and genetic algorithm,an integrated optimization framework of the design of the conformal rotor and nacelle is built.Then,a geometrically compatible integrated optimization for the rotor and nacelle is carried out with the objective of maximizing energy efficiency in the full mission profile.Finally,a conformal rotor and nacelle design solution is obtained,which satisfies geometric compatibility and thrust constraints while providing high thrust efficiency and low cruising drag.A comparison of the results of the integrated design and the conventional rotor optimization design shows that the drag of the conventional rotor is 3.45 times that of the conformal integrated design in the cruising state,which proves the effectiveness and necessity of the proposed method.
文摘This paper creates 3D solid model and assembly of U RJ 92-6 oil tank and analyses its strength by integrated CAD/CAE/CAM software I-D EAS. Through integrated simulation in computer, design efficiency and quality of oil tank is greatly improved. Adopting integrated CAD/CAE/CAM software to carry out integrated research to equ ipment and products, we will be able to take overall analysis in aspects of 3-D solid modeling, pre-assembly and strength, etc., to realize non-paper designi ng and parallel designing. Problems can be found and settled during designing, w hich will increase designing efficiency and one-time success rate and realize o ptimum designing for products.
基金National High-tech R&D Program (863 Program) (2006AA04Z144)Key Technologies R&D Program (2006BAF04B02).
文摘An integration system was developed to satisfy the need of information integration in the process of designing, investment casting and monitoring aero-engine's turbo blade. The general architecture is detailed presented in this paper. The system mainly comprises of product master model, design information management, anti-deformation design of mould cavity, intelligence mould design and blade testing. The developed system can manage mould design and blade test data flow, optimize mould design process and achieve the goal of integration design.
基金This project is supported by National Natural Science Foundation of China (No.59990470)Doctoral Foundation of Ministry of Education, China(No.20010487024).
文摘The integrated layout problem in manufacturing Systems is investigated. Anintegrated model for Concurrent layout design of cells and flow paths is formulated. A hybridapproach combined an enhanced branch-and-bound algorithm with a simulated annealing scheme isproposed to solve this problem. The integrated layout method is applied to re-layout the gear pumpshop of a medium-size manufacturer of hydraulic pieces. Results show that the proposed layout methodcan concurrently provide good solutions of the cell layouts and the flow path layouts.
基金the National Natural Science Foundation of China，the China Postdoctoral Science Founda-tion
文摘The aerodynamic performance, structural strength, and wheel weight are three important factors in the design process of the radial turbine for micro gas turbines. This study presents the experimental validation process of this integrated optimization design method by using the similarity theory. Cold modeling tests and investigations into the aerodynamic characteristics were performed. Experimental results showed that the aerodynamic efficiency of the micro radial turbine is 84.3% at the design point while also satisfying the aerodynamic and strength requirements. Meanwhile, the total weight of the turbine wheel is 3.8 kg which has only a 52.8% mass of the original design. This indicates that the radial turbine designed through this technique has a high aerodynamic performance, and thus can be applied to micro gas turbines. The results validated that this integrated optimization design method is reliable.
基金Supported by the National Key Research and Development Program of China under Grant No 2017YFA0204600the National Natural Science Foundation of China under Grant No 61404002the Science and Technology Project of Hunan Province under Grant No 2015JC3041
文摘An analytical model for current-voltage behavior of amorphous In-Ga-Zn-O thin-film transistors（a-IGZO TFTs）with dual-gate structures is developed.The unified expressions for synchronous and asynchronous operating modes are derived on the basis of channel charges,which are controlled by gate voltage.It is proven that the threshold voltage of asynchronous dual-gate IGZO TFTs is adjusted in proportion to the ratio of top insulating capacitance to the bottom insulating capacitance（C_（TI）/C_（BI））.Incorporating the proposed model with Verilog-A,a touch-sensing circuit using dual-gate structure is investigated by SPICE simulations.Comparison shows that the touch sensitivity is increased by the dual-gate IGZO TFT structure.
文摘This study integrated instrumental and relational approaches to the teaching and learning of solids in a preservice teacher＇s class. The researcher guided the preservice teachers to gather various prisms, pyramids, and spheres to study the total surface areas and volumes. At the end of the integrated models, the test scores showed closed relationships in the concurrent instructional strategies of the integrated models. The researcher therefore, recommended the design models for the teaching and learning of solids in mathematics.
文摘This paper describes how database information and electronic 3D models are integrated to produce power plant designs more efficiently and accurately. Engineering CAD/CAE systems have evolved from strictly 3D modeling to spatial data management tools. This paper describes how process data, commodities, and location data are disseminated to the various project team members through a central integrated database. The database and 3D model also provide a cache of information that is valuable to the constructor, and operations and maintenance Personnel.
文摘The overall teaching design for the junior middle school English unit aims to maximize the use of teaching resources by using the unit as the central theme,integrating it throughout all sections and related activities.This approach continually reinforces students’understanding and retention of individual lesson content while fostering their core literacy and skills.It promotes a comprehensive development of students’listening,speaking,reading,and writing skills,allowing them to engage repeatedly with the language materials until they internalize them as part of their language proficiency.
