Some comments on air condensation effects in a hypersonic helium tunnel

Abstract

Apart from some earlier experimental work by Henderson and Swalley, there does not appear to be available in the literature an analysis of the effects of small amounts of air contamination on the flow of helium in a hypersonic nozzle. The main difference between this and the more common problem of condensation of water vapour in air or of a condensing diatomic gas alone, is that the mass fraction of the contaminant cannot be ignored. In this Report a brief analysis of the problem is outlined and the more important points discussed. The theoretical and experimental results are compared with those of Henderson and Swalley.