Numerical and experimental investigation of the hypersonic flow structure in a complex flat duct

1 / 15

AERODYNAMICS AND HEAT EXCHANGE
PROCESSES OF AIRCRAFT
NUMERICAL AND EXPERIMENTAL INVESTIGATION
OF THE HYPERSONIC FLOW STRUCTURE IN A COMPLEX FLAT DUCT
M.A. Kotov, I.A. Kryukov, L.B. Ruleva,
S.I. Solodovnikov , S.T. Surzhikov
Institute for Problems in Mechanics of the Russian Academy of Sciences
e-mail: ; ;
;
Experimental and numerical investigation was performed to determine the hypersonic
flow structure in a complex flat duct simulating the air intake and flow passage in a
hypersonic ramjet. The testing setup is described in detail. Mach 7 and Mach 4.5 air
flows are studied by means of high-speed digital video cameras in the flat ducts formed
by sharp and blunt-nose wedges. The duct internal surface was either smooth or had
trapezoid cavities similar to flameholders in a hypersonic ramjet engine combustion
chamber. The numerical simulation was conducted with the software (computer
code) integrating the Navier-Stokes equation system. The comparison of testing
and computational data proves that numerical simulation can provide accurate
description of the experimental flow structure. The numerical and experimental
results clearly present hypersonic flow field structure in complex configuration ducts.
Simultaneous computational and experimental investigation enhances the reliability
of the aerodynamic data obtained.
Keywords: shock tube, experimental investigation, hypersonic flows, shockwave
mathematical modelling, gas dynamics equations, compressible Navier–Stokes
equations, finite volume approach.
Problem description. Intensive physical processes near the surface of
the aerospace and hypersonic aircraft (HA) justify the investigation of high-
speed and high-temperature gas flows normally accompanied by a multitude
of non-linearly related physical processes, which stipulates a complex
approach drawing both on the physical experiment and corresponding
computational models.
Such investigations require physical processes data obtained from
(geometrically-) scaled model testing in a shock tube [1]. These setups are
a fairly convenient tool for a wide range of aerodynamics and physical
dynamics problems and enable validation of numerical methods. Short
duration of gas dynamics processes in the shock tube working path
which complicates measurements is canceled out by low-inertia sensors,
noncontact measuring equipment (shadow column devices, interferometers)
[2–4] based on optical instruments and new generation high-speed recording
and processing equipment.
This paper presents the results of the experimental and numerical
investigation of shockwave patterns as a result of hypersonic flow past
HA elements. Aerodynamic models of the following flat duct types were
studied:
4 ISSN 0236-3941. HERALD of the BMSTU. Series “Mechanical Engineering”. 2015. No. 1