Calculation of the turbulent two-phase flow in direct-injection diesel engine
To calculate the governing equations for the turbulent two-phase flow the CFD code (KIVA-3V) was changed to fit for the gas phase and the liquid phase. In the gas phase, the Favre-averaging is used for die continuity equation and momentum equation. As a result of the averaging, unclosed terms appear which require modeling. In order to make the turbulent Reynolds stress tensor closed in the momentum equation, the so-called Boussinesqueapproximation, which is based on an analogy between molecular diffusion and diffusion turbulent eddies, was employed. The equations for turbulent kinetic energy k and turbulent dissipation ε were added to close the Navier-Stokes equations. The temporal differencing scheme in KIVA-3V is largely implicit. In the Lagragian phase, implicit differencing was used for all diffusion terms and terms associated with pressure wave propagation. A method similar to the SIMPLE-algorithm was used to solve the coupled implicit set of equations. In the liquid phase, the probability density function (PDF) method was used for solving the droplet spray equation. The Taylor analogy breakup (TAB) model used in me standard KIVA-code was extended with a deformation velocity such that their lifetime was extended to match experimentally observed jet breakup lengths. Furthermore, other models such as the Rayleigh-Taylor(R-T) model, discrete droplet models (DDM) etc. were discussed. Finally, cylinder pressure and corresponding heat release rates in a directed-injection diesel engine were calculated and compared with the experiments. It gives the theory and method about calculating turbulence exactly in directed-injection diesel engines.
Yong-feng Liu You-tong Zhang Hong-seng Tian Jian-jun Qin
School of Mechanical and Vehicular Engineering, Beijing Institute of Technology, Beijing 100081, Chi School of Mechanical and Vehicular Engineering, Beijing Institute of Technology, Beijing 100081, Chi School of Mechanical-Electronic and Automobile Engineering, Beijing Institute of Civil Engineering a School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University,Beijing 100044
国际会议
The 5th International Conference on Nonlinear Mechanics(第五届国际非线性力学会议)
上海
英文
1026-1031
2007-06-11（万方平台首次上网日期，不代表论文的发表时间）