ILES of an array of three subsonic counter-flow jets issuing from a wing leading edge exposed to hypersonic aerodynamic heating

Tomonori Shimada,Taku Ohwada

doi:10.1186/s42774-020-00037-8

Abstract

The flow of an active thermal protection system exploiting subsonic counter-flow jets for wing leading edges of hypersonic vehicles is numerically studied on the basis of the three dimensional Navier-Stokes equations. The coolant air issuing from around the stagnation point as an array of three jets spreads over both the upper and the lower sides of the cylinder surface and about 40 ~ 60% cooling effectiveness is achieved in the range up to 5 degrees angle of attack despite the occurrence of various three-dimensional fluid-dynamic instabilities. The numerical scheme is second order accurate but simple inclusion of high order polynomial approximation in the reconstruction enables the capturing of finer structure of the flow field.

Highlights

The development of active thermal protection system (TPS) exploiting counter-flow jets for nose caps and wing leading edges of hypersonic vehicles is an old and new problem, which has been studied since the early days of space program [1,2,3,4,5,6,7,8]
5 Concluding remarks The present 3D simulation of the active TPS exploiting an array of three subsonic counter-flow jets exhibited various fluid-dynamic phenomena such as jet flapping, RT and KH instabilities, bypass transition in separation bubbles, turbulent boundary layers and heat flux distribution of stripe pattern caused by near-wall streaks
Longitudinal vortex rolls generated by the RT and KH instabilities occasionally wiped out the coolant air on a large scale and dragged the high temperature air there, which caused the performance decrease

Summary

Introduction

The development of active thermal protection system (TPS) exploiting counter-flow jets for nose caps and wing leading edges of hypersonic vehicles is an old and new problem, which has been studied since the early days of space program [1,2,3,4,5,6,7,8]. Still fresh in our minds is the Antipode (https://edition.cnn.com/travel/article/antipodehypersonic-concept-plane/index.html), a concept design of a hypersonic commercial airplane, which is equipped with supersonic counter-flow jets in the long penetration mode (LPM) for reducing drag and heat and flies from New York to London in 11 min. This paper is written as a newsletter about our latest study concerning the feasibility of active TPS exploiting subsonic counter-flow jets for wing leading edges of hypersonic vehicles. In our previous study [9] a uniform hypersonic flow past a cylinder with

Objectives

Results

Conclusion