This paper contributes to the diffraction of a solitary Wave by a cylinder, governed by the Boussinesq eq. The Spectrum Method is used to transform 2-D eqs. into a set of 1-D eqs., which is solved by F. D. M. The exam...This paper contributes to the diffraction of a solitary Wave by a cylinder, governed by the Boussinesq eq. The Spectrum Method is used to transform 2-D eqs. into a set of 1-D eqs., which is solved by F. D. M. The example given in the paper shows that this method is both accurate and cost ef- fective.展开更多
Aerodynamic simulation of high-speed trains has been carried out by using Lattice Boltzmann Method (LBM). Non-simplified train model was used and the number of space grids reached tens of millions. All results under d...Aerodynamic simulation of high-speed trains has been carried out by using Lattice Boltzmann Method (LBM). Non-simplified train model was used and the number of space grids reached tens of millions. All results under different working conditions reflected the actual situation.展开更多
More and more importance has been attached to inductively coupled plasma (ICP) in semiconductor manufacture. For a deep understanding of the plasma discharge process in the etching reactor, this study made a three-dim...More and more importance has been attached to inductively coupled plasma (ICP) in semiconductor manufacture. For a deep understanding of the plasma discharge process in the etching reactor, this study made a three-dimensional simulation on the Ar plasma discharge process with the commercial software CFD-ACE, which is according to the real experiment conditions and data supplied by North Microelec-tronic Corporation. The error of the simulation results is in the range of ±20% with credibility. The numerical results show that the three-dimentional spatial distribu-tion of electron density is reduced from the chamber center to the wall. The distri-bution of electron density, electron temperature and power deposition is related to the shape and placement of the coil.展开更多
There is a growing interest in propellers for transport aircraft as well as regional airliners from the viewpoint of energy saving. An important consideration for utilizing a propeller propulsion system on aircraft is...There is a growing interest in propellers for transport aircraft as well as regional airliners from the viewpoint of energy saving. An important consideration for utilizing a propeller propulsion system on aircraft is the aerodynamic interaction between the propeller slipstream and other aerodynamic surfaces. It is therefore necessary to use a simplified but relatively accurate tool for propeller modeling, with the widely used actuator disk model. The advantage of this model is that it is easy to use and inex- pensive in terms of computation time required. In addition, it also produces acceptable results. In this study, a new regionalized actuator disk model was utilized in the analysis of propeller slipstream interference effects on a real four-propeller aircraft. The results are compared with the cases of inactive actuator disks, which shows that the propeller slipstream causes an increase in the lift and drag coefficients. An evident yawing effect caused by the rotating slipstream was noticed, which should be taken into account in the design phase. The regionalized actuator disk model is evaluated as a fast and relatively accurate model for propeller preliminary design.展开更多
This article treats transient motions induced by some kind of obstacles. The gravity effect of the surface elevation is simulated by a set of distributed doub- lets. An integro-differential equation is derived and sol...This article treats transient motions induced by some kind of obstacles. The gravity effect of the surface elevation is simulated by a set of distributed doub- lets. An integro-differential equation is derived and solved numerically. Three examples are given: (1) a non-uniform distribution of the elevation of initial water surface, (2) the impinging of a falling body, and (3) the sudden starting of an underwater obstacle. There is an analytical solution for the first example, our numerical result agrees with it vary well.展开更多
文摘This paper contributes to the diffraction of a solitary Wave by a cylinder, governed by the Boussinesq eq. The Spectrum Method is used to transform 2-D eqs. into a set of 1-D eqs., which is solved by F. D. M. The example given in the paper shows that this method is both accurate and cost ef- fective.
文摘Aerodynamic simulation of high-speed trains has been carried out by using Lattice Boltzmann Method (LBM). Non-simplified train model was used and the number of space grids reached tens of millions. All results under different working conditions reflected the actual situation.
文摘More and more importance has been attached to inductively coupled plasma (ICP) in semiconductor manufacture. For a deep understanding of the plasma discharge process in the etching reactor, this study made a three-dimensional simulation on the Ar plasma discharge process with the commercial software CFD-ACE, which is according to the real experiment conditions and data supplied by North Microelec-tronic Corporation. The error of the simulation results is in the range of ±20% with credibility. The numerical results show that the three-dimentional spatial distribu-tion of electron density is reduced from the chamber center to the wall. The distri-bution of electron density, electron temperature and power deposition is related to the shape and placement of the coil.
基金supported by the Key Projects in the National Science&Technology Pillar Program during the Eleventh Five-Year Plan Period(Grant No.2009BAG12A01)
文摘There is a growing interest in propellers for transport aircraft as well as regional airliners from the viewpoint of energy saving. An important consideration for utilizing a propeller propulsion system on aircraft is the aerodynamic interaction between the propeller slipstream and other aerodynamic surfaces. It is therefore necessary to use a simplified but relatively accurate tool for propeller modeling, with the widely used actuator disk model. The advantage of this model is that it is easy to use and inex- pensive in terms of computation time required. In addition, it also produces acceptable results. In this study, a new regionalized actuator disk model was utilized in the analysis of propeller slipstream interference effects on a real four-propeller aircraft. The results are compared with the cases of inactive actuator disks, which shows that the propeller slipstream causes an increase in the lift and drag coefficients. An evident yawing effect caused by the rotating slipstream was noticed, which should be taken into account in the design phase. The regionalized actuator disk model is evaluated as a fast and relatively accurate model for propeller preliminary design.
文摘This article treats transient motions induced by some kind of obstacles. The gravity effect of the surface elevation is simulated by a set of distributed doub- lets. An integro-differential equation is derived and solved numerically. Three examples are given: (1) a non-uniform distribution of the elevation of initial water surface, (2) the impinging of a falling body, and (3) the sudden starting of an underwater obstacle. There is an analytical solution for the first example, our numerical result agrees with it vary well.
