EXPERIMENTAL STUDY OF PSEUDO TRANSPIRATION AT AN ORIFICE IN RAREFIED FLOW.
Abstract
An experimental investigation of the low-density orifice effect, which occurs on a body that is not in thermal equilibrium with the ambient flow, was performed with a sharp flat plate under hypersonic, rarefied flow conditions. The surface pressure, measured directly with pressure transducers mounted flush with the model surface, was as much as three times larger than the pressure measured with similar transducers mounted in a cavity and vented to the surface through an orifice. The physical origin of the effect is described and an existing semi-empirical method for predicting this effect is reviewed. This method is tested with the data to assess its accuracy, and it is found to underestimate the effect by about 20% plus or minus 20%. It appears that this discrepancy might stem from a temperature effect not included in the method. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 1968
- Accession Number
- AD0678602
Entities
People
- John A. Bartz
- Robert J. Vidal
Organizations
- Calspan