AERODYNAMIC AND HEAT TRANSFER STUDIES WITH EVAPORATIVE FILM COOLING AT HYPERSONIC MACH NUMBERS
Abstract
A theoretical model of evaporative film cooling was developed for blunt bodies indicating the effect of mass transfer on heat transfer for Prandtl and Lewis numbers unity. The velocity of the liquid film at the gas-liquid interface is assumed to be so small that the gaseous phase is unaffected. This assumption was verified by a numerical example from the analysis. With this approximation the effect of mass transfer (evaporation from the liquid film) on heat transfer from the gas-phase boundary layer was obtained from the literature on transpiration cooling. The velocity profile through the liquid film was found to be identical to that of a Couette flow with pressure gradient. The evaporative film cooling experiments were con ducted on hemisphere- cylinder, blunted cone, and flat-faced cylinder models at Mach Number 6.8 in a high temperature hypersonic blowdown wind tunnel at the Rosemount Aeronautical Laboratories.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1962
- Accession Number
- AD0404197
Entities
People
- Rudolf Herman
- W. L. Melnik
Organizations
- University of Minnesota