S_2流面正命题适用于纯物质流体的变分原理族及实际蒸汽跨声流动的变分有限元解

FAMILY OF VARIATIONAL PRINCIPLES FOR DIRECT PROBLEM OF PURE SUBSTANCE FLOW ALONG S_2-STREAMSHEET AND A FINITE ELEMENT SOLUTION OF TRANSONIC STEAM FLOW

一、前言 自从叶轮机械基于两类流面迭代的三元流动通用理论提出以来,国内外在对叶轮机械的各种气动命题的求解方面已作大量工作,并得到令人满意的计算结果。但在流动工质的物性对流动的影响方面开展工作尚少,尤其在变分有限元计算方面,几乎还是空白。

A family of variationai principles for the direct problem of S2-flow of pure substance in axial-flow turbomachinery is established in this paper. With these variationai principles, a direct problem of transonic flow along axial-flow S2-ctreamsheet is solved by the finite element method for three model substances: steam, perfect gas I and II with the specific heat ratios of 1,4 and 1.115 respectively. The present results are useful in the design of turbomachines using imperfect gases, such as steam, freon etc.