Effects of transpiration fluid properties on Boundary Layer Instability Mechanisms

ORAL

Abstract

The management of intense thermal loads encountered by hypersonic vehicles operating in the atmosphere

can be effectively alleviated by utilizing transpiration cooling, which involves the injection of cold fluids at

the vehicle’s surface. However, injection can substantially impact flow stability and potentially

induce a premature transition to turbulence. The primary objective of this study is to comprehensively

understand the mechanisms responsible for the destabilization of the flow for different injection fluids. To

assess the influence of injection gas properties on the stability of high-enthalpy boundary layer flows, air

and CO2 injections are being considered. Both fluids are introduced at the same mass flux, resulting in

a comparable reduction in heat flux. Disturbance energy budget analysis is used to explain the relevant physical mechanisms. Furthermore, Bi-Orthogonal Decomposition is used to differentiate the different contributions from eigenmode spectrum.

Publication: Saikia, B., and Brehm, C., "Effects of Injection Gas Composition on the Stability of a High-Enthalpy Flow over a Blunt Cone,"
8-12 January 2024, Orlando, FL, https://doi.org/10.2514/6.2024-1977

V. Russo, Saikia, B., and Brehm, C., "Stability Investigation of High Enthalpy Boundary Layer Flow with Gas Injection using Energy Budget Analysis", (submitted to AIAA Aviation 2024)

Presenters

  • Vincenzo Russo

    University of Maryland, College Park

Authors

  • Vincenzo Russo

    University of Maryland, College Park

  • Bijaylakshmi Saikia

    University of Maryland

  • Christoph Brehm

    University of Maryland College Park, University of Maryland