Effects of Blowing Ratio on Heat Transfer to the Throat Region of a Porous-Walled Nozzle.
Abstract
This experiment analyzed the effects of blowing ratio on heat transfer to the throat region of a porous-walled nozzle, using the AFIT low speed shock tube. Heat flux data were taken from both sides of a two-dimensional Mach 2.0 (Re/m=5.2x10(exp 7) nozzle using thin film resistance thermometers. One side was transpiration-cooled by secondary air injection through a sintered wall, while the other side served as a control. Control results were validated using empirical relations, and cooled side results showed up to a 14% reduction in heat transfer coefficient at blowing ratios of only 0.51%. The linear nature of cooling effectiveness at these low blowing ratios allowed a modification of nozzle heat transfer equations to include a blowing ratio parameter. Disturbance of primary flow was also minimized, causing no measurable reduction of nozzle performance.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 01, 1994
- Accession Number
- ADA289459
Entities
People
- Joseph L. Lenertz
Organizations
- Air Force Institute of Technology