Theoretical Aeordynamics Research
Abstract
The blunted-nose high-pressure drag is shown to exert great impact on the hypersonic flow field even in the strong interaction regime governed by viscous effects. This impact vanishes downstream where the viscous/invicid interaction becomes dominant. Optimization of conical wings in hypersonic flight substantially reduces the wave drag. A pertinent figure of merit F=CD/CL3/2 decreases by more than 4%. The concept of absolute instability in the streamwise and crossflow directions is a breakthrough in our understanding of boundary-layer properties on swept wings and gas-turbine blades where the flow field is highly three-dimensional. Many contradictions in this area were building up for decades and eventually cast doubts on the very validity of hydrodynamic stability theory. No reliable transition-prediction methods could exist on this basis. New methods to be developed in place of those used currently must incorporate the possibility of earlier transition due to upstream advancing wave packets.
Document Details
- Document Type
- Technical Report
- Publication Date
- Mar 01, 2000
- Accession Number
- ADA376319
Entities
People
- Julian D. Cole
- Oleg S. Ryzhov
Organizations
- Rensselaer Polytechnic Institute