摘要
针对直喷式柴油发动机燃烧后散发的主要有害物 (Soot和NOx) ,提出了有代表性的小火焰模型 ,用来污染物预测 .此模型根据湍流火焰可看成极细小的 ,极小空间的一维小火焰的假设 ,提供了一种将湍流化学反应场和湍流运动场分离开的方法 .此模型通过引入混和比分数Z参数空间坐标 ,将复杂的湍流燃烧坐标系转化到Z参数坐标系下 ,建立小火焰方程 .输入有代表性小火焰方程一系列参数 ,通过与计算流体动力学的程序 (KIVA - 3V)连接计算出各种物质的混合比分数 ,从而计算出燃烧后各种物质(主要是有害物质 )的组成比例 .
The representative interactive flamelet(RIF)model is presented and used for pollution prediction for Direct Injector Diesel engine. The model, which is based on the notion that a turbulent flame can be viewed as an ensemble of thin, locally one-dimensional flamelets, offers a way of separating the numerical effort associated with the solution of the turbulent flow field from that of solving the chemistry. The model uses Z coordinate and builds flamelet equations.Base on a set of parameters representative of a certain flamelet, the flamelet code calculates species profiles by the CFD-code over mixture fraction. Turbulent mean values are obtained by weighting these profiles of the mixture fraction.
出处
《北京建筑工程学院学报》
2004年第3期26-29,共4页
Journal of Beijing Institute of Civil Engineering and Architecture
基金
北京建筑工程学院青年基金项目
