Control of Boundary Layer Instability in Hypervelocity Flow
Abstract
Previous theoretical work predicted that hypersonic boundary layer instability could be controlled by ultrasonically absorptive wall treatment. Experiments were performed to test this theory by constructing a model, a 5 deg. half-angle cone, with very fine porosity on one side and a solid surface on the other, and testing it in the hypervelocity shock tunnel at Caltech. The results show that a dramatic delay of transition could be achieved in the nitrogen flow for which the porosity was designed. In carbon-dioxide flows, for which the transition Reynolds number is much higher at the high enthalpies of the experiments, the porosity on the model is too coarse and acts like roughness, actually advancing transition. The transition delay achievable with proper porosity design promises large reduction of heat loads on launch and reentry vehicles.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 31, 2002
- Accession Number
- ADA400109
Entities
People
- H. G. Hornung
Organizations
- California Institute of Technology