HYPERSONIC BOUNDARY-LAYER TRANSITION ON CONTROL SURFACES WITH SEPARATION BUBBLES
Abstract
Accurate prediction of boundary-layer transition remains critical to the design of hypersonic vehicles, due to the dramatic effect of transition on heat transfer, boundary-layer separation, and aerodynamic control authority. Although much progress has been made in understanding the basic mechanisms of transition, vehicle designers usually predict transition using simple correlations. The uncertainties in these correlations are large for a new hypersonic vehicle, generating high levels of development risk and tendencies towards less-effective but conservative designs. Furthermore, no single ground test can simulate all aspects of hypersonic transition, and nearly all ground tests are corrupted by the high levels of test-section noise in conventional hypersonic tunnels. Numerical simulations are critical for predicting flight, but all such simulations must incorporate empirical models for some of the physical elements. Computational and experimental efforts must be coordinated to enable the development of mechanism-based prediction methods for effective design of flight vehicles. Transition affects the heat transfer to control effectors such as body flaps and transverse jets, and it also affects the forces and moments induced by these effectors. These control effectors usually induce separation bubbles, which cause transition to occur much earlier. Transition affects separation and separation affects transition. In the last couple of decades, quiet tunnels have improved, along with experimental instrumentation, and much improved computational analyses are available. The NATO STO task group AVT-346 has collected a group of researchers from France, Germany, the U.S. and other nations who are developing cooperative efforts to improve mechanism-based prediction methods for hypersonic transitional flows past compression corners with separation bubbles.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Mar 07, 2023
- Source ID
- FA95502210110
Entities
People
- Steven Schneider
Organizations
- Air Force Office of Scientific Research
- Purdue University
- United States Air Force