侧压式进气道附加阻力分析

Analysis of additive drag in sidewall-compression inlet

关键词:  侧压式进气道+  附加阻力+  分析

Key words:  Sidewall-compression inlet+  Additive drag+  Analysis

摘要:

以侧压式进气道的附加阻力特性为研究对象,以流线跟踪得到的捕获流管为分析体,讨论进气道不同几何设计参数下喉道截面前捕获流管的阻力特性;以数值模拟为手段,分析了附加阻力作用表面的形状和变化特征,讨论了侧压式进气道流线偏转导致溢流的机理,给出了进气道几何参数变化对附加阻力的影响关系。研究发现,唇口前的溢流会产生"附加推力"而不是通常情况的附加阻力;附加推力随收缩比增加而增加,大小和流管作用的摩擦阻力处于同一水平。

Abstract:

The effect of different geometry parameter on the additive drag of sidewall-compression inlet is presented for the requirement of scaramjet drag characteristics.Captured streamtubes formed from stream-tracing are used to analyze additive drags.The streamsurface on which the additive drag acts is given by numerical investigation.Shape and characteristics of the stream-surface are investigated.The relationship between geometry parameters of inlets to additive drags is discussed.It is surprised that the additive drag becomes the additive thrust in sidewall-compression inlet.It is found that additive thrust increases with contraction ratio.The proportion of additive thrust is similar to that of the friction drag produced by the captured streamtube.