The interaction of a rarefaction wave with a gradual monotonic area enlargement of finite length in a duct or pipe is studied both analytically and numerically. A quasi-steady flow analysis that is analytical for an inviscid flow of a perfect gas is presented first, to obtain asymptotic solutions for the flow at late times, after all transient disturbances from the interaction process have subsided. Analytical results are given and discussed for the boundary between the two possible asymptotic wave patterns that are predicted and the corresponding asymptotic strengths of the transmitted, reflected and other waves, all as a function of both the incident rarefaction-wave strength and area-enlargement ratio. 41 refs.
|Title of host publication||UTIAS Technical Note (University of Toronto, Institute for Aerospace Studies)|
|State||Published - 1 Dec 1984|