基于分段控制的MMPC排气管段几何建模方法

The Building Method of MMPC Exhaust Pipe Geometry Model Based on Segment Control

MMPC系统排气歧管出口形状与入口形状有较大差异。为降低歧管内的流动损失,需要入口形状沿歧管轴线平滑过渡到出口形状,确定歧管截面形状沿歧管轴线的分布规律是实现平滑过渡的前提。给出一种基于分段控制的MMPC排气歧管几何建模方法,建立对出口、入口形状近似程度不同的一组截面,通过各截面在扫描路径上的位置变化,控制MMPC排气歧管段的平滑过渡,为MMPC排气管段的优化设计建立基础。

For the MMPC exhaust pipe system, the exhaust branch＇s outlet shape is different from that of the inlet. The smooth transition from the inlet to the outlet is necessary for decreasing the inner flow＇s pressure loss. The variation of the cross section along the exhaust branch＇s axis is the foundation for producing a smooth transition. However, the section data are few and bring trouble for the design of the MMPC exhaust system. In this paper, a method with segment control technique for building the geometry model of MMPC exhaust pipe is introduced. The method builds a set of sections which approximates the inlet and outlet shape differently at first. And the MMPC branch＇ s geometry is controlled by changing the position of the cross section selected, The work in this paper serves for the optimization of the MMPC exhaust pipes.