A parallelized upwind flux splitting scheme for supersonic reacting flows on hybrid meshes is presented. The complexity of super/hyper-sonic combustion flows makes it necessary to establish solvers with higher resolut...A parallelized upwind flux splitting scheme for supersonic reacting flows on hybrid meshes is presented. The complexity of super/hyper-sonic combustion flows makes it necessary to establish solvers with higher resolution and efficiency for multi-component Euler/N-S equations. Hence, a spatial second-order van Leer type flux vector splitting scheme is established by introducing auxiliary points in interpolation, and a domain decomposition method used on unstructured hybrid meshes for obtaining high calculating efficiency. The numerical scheme with five-stage Runge-Kutta time step method is implemented to the simulation of combustion flows, including the supersonic hydrogen/air combustion and the normal injection of hydrogen into reacting flows. Satisfying results are obtained compared with limited references.展开更多
Due to the practical problems of the high costs and the long development cycle of China’s cabinet production,a computer-aided design method of the cabinet based on style imagery is proposed.According to the principle...Due to the practical problems of the high costs and the long development cycle of China’s cabinet production,a computer-aided design method of the cabinet based on style imagery is proposed.According to the principle of the conjoint analysis method, the rough set theory and the weight coefficient of different components of the cabinet,a multi-dimensional model of style imagery to evaluate the cabinet is built. Then the related constants of style imagery are calculated and the cabinet components library is also built by the three-dimensional modeling.Finally,with recombinant technology and the mapping model between cabinet style and external characteristics,the prototype system based on Visual Studio is proposed.This system actualizes the bidirectional reasoning between product style imagery and the shape features,which can assist designers to produce more creative designs,greatly improve the efficiency of cabinet development and increase the profits of companies.展开更多
Today, more people are riding bicycles than ever before--and the numbers keep growing. This is due in part to a greater awareness of environmental issues and growing health consciousness. Another factor driving the in...Today, more people are riding bicycles than ever before--and the numbers keep growing. This is due in part to a greater awareness of environmental issues and growing health consciousness. Another factor driving the increasing number of women bicyclists today is many designer bicycles now available. Still, these bicycles reflect the subjective sensibilities of their designers, and there is no guarantee that they will always match an increasingly diverse array of consumer values. In response to this challenge, our study sets out to build a bicycle design model based on fashion styles popular with young women in their 20s. Fashion analysis and bicycle design analysis used statistical science, such as cluster analysis, principal component analysis, and analytic hierarchy process （AHP）. After that, we designed a new bicycle using computer-aided design （CAD） from the analysis results. Finally, the approach model developed in this study was confirmed to be effective by an interview with the company.展开更多
With the rapid development of the computational fluid dynamics(CFD),a parameter-free upwind scheme capable of simulating all speeds accurately and efficiently is in high demand.To achieve this goal,we present a new up...With the rapid development of the computational fluid dynamics(CFD),a parameter-free upwind scheme capable of simulating all speeds accurately and efficiently is in high demand.To achieve this goal,we present a new upwind scheme called AUSMPWM in this paper.This scheme computes the numerical mass flux as the AUSMPW+and computes the interfacial sound speed in a different way.Also,it computes the pressure flux by limiting the dissipation if the Mach number is less than 1.Series of numerical experiments show that AUSMPWM can satisfy the following attractive properties independent of any tuning coefficient:(1)Robustness against the shock anomaly and high discontinuity’s resolution;(2)high accuracy on hypersonic heating prediction and capability to give smooth reproductions of heating profiles;(3)low dissipation at low speeds;and(4)strong grid,reconstruction scheme,and Mach number independence in low speeds’simulations.These properties suggest that AUSMPWM is promising to be widely used to accurately and efficiently simulate flows of all speeds.展开更多
文摘A parallelized upwind flux splitting scheme for supersonic reacting flows on hybrid meshes is presented. The complexity of super/hyper-sonic combustion flows makes it necessary to establish solvers with higher resolution and efficiency for multi-component Euler/N-S equations. Hence, a spatial second-order van Leer type flux vector splitting scheme is established by introducing auxiliary points in interpolation, and a domain decomposition method used on unstructured hybrid meshes for obtaining high calculating efficiency. The numerical scheme with five-stage Runge-Kutta time step method is implemented to the simulation of combustion flows, including the supersonic hydrogen/air combustion and the normal injection of hydrogen into reacting flows. Satisfying results are obtained compared with limited references.
基金The National Natural Science Foundation of China(No.71271053)the Scientific Innovation Research of College Graduates in Jiangsu Province(No.CXLX13_082)
文摘Due to the practical problems of the high costs and the long development cycle of China’s cabinet production,a computer-aided design method of the cabinet based on style imagery is proposed.According to the principle of the conjoint analysis method, the rough set theory and the weight coefficient of different components of the cabinet,a multi-dimensional model of style imagery to evaluate the cabinet is built. Then the related constants of style imagery are calculated and the cabinet components library is also built by the three-dimensional modeling.Finally,with recombinant technology and the mapping model between cabinet style and external characteristics,the prototype system based on Visual Studio is proposed.This system actualizes the bidirectional reasoning between product style imagery and the shape features,which can assist designers to produce more creative designs,greatly improve the efficiency of cabinet development and increase the profits of companies.
文摘Today, more people are riding bicycles than ever before--and the numbers keep growing. This is due in part to a greater awareness of environmental issues and growing health consciousness. Another factor driving the increasing number of women bicyclists today is many designer bicycles now available. Still, these bicycles reflect the subjective sensibilities of their designers, and there is no guarantee that they will always match an increasingly diverse array of consumer values. In response to this challenge, our study sets out to build a bicycle design model based on fashion styles popular with young women in their 20s. Fashion analysis and bicycle design analysis used statistical science, such as cluster analysis, principal component analysis, and analytic hierarchy process （AHP）. After that, we designed a new bicycle using computer-aided design （CAD） from the analysis results. Finally, the approach model developed in this study was confirmed to be effective by an interview with the company.
基金supported by the National Basic Research Program of China("973"Project)(Grant No.2009CB724104)
文摘With the rapid development of the computational fluid dynamics(CFD),a parameter-free upwind scheme capable of simulating all speeds accurately and efficiently is in high demand.To achieve this goal,we present a new upwind scheme called AUSMPWM in this paper.This scheme computes the numerical mass flux as the AUSMPW+and computes the interfacial sound speed in a different way.Also,it computes the pressure flux by limiting the dissipation if the Mach number is less than 1.Series of numerical experiments show that AUSMPWM can satisfy the following attractive properties independent of any tuning coefficient:(1)Robustness against the shock anomaly and high discontinuity’s resolution;(2)high accuracy on hypersonic heating prediction and capability to give smooth reproductions of heating profiles;(3)low dissipation at low speeds;and(4)strong grid,reconstruction scheme,and Mach number independence in low speeds’simulations.These properties suggest that AUSMPWM is promising to be widely used to accurately and efficiently simulate flows of all speeds.
