Community Research and Development Information Service - CORDIS

Aerothermodynamics of space vehicles and space debris

Numerical and experimental investigations of aerothermodynamics of one of the most frequent elements of space vehicles (compression corner) and space debris have been carried out in a wide range of the flow regimes (from continuum to free molecular).

1. Models of compression corner have been developed and fabricated, and experimental investigations have been carried out to study the surface pressure distributions, limiting streamlines and heat flux fields in the wind tunnels of ITAM SO RAS T 313 (Moo = 3 and 6) and T 326 (Moo = 6 and 8). The data on the pressure distributions in compression corners have been obtained at Moo = 3 that characterize the onset and development of the boundary layer separation. The maximum pressure levels on the surfaces have been measured for various angles id. At Moc: = 6 and 8, the heat flux fields have been obtained near the inflection line for ,B = 15° and 25°. An explicit periodic structure (alternation of streamwise bands with elevated and reduced heat fluxes) has been found in the cross sections near the reattachment of separated flows in the conditions of the laminar boundary layers and realized shock intensities. It is shown that the band structure observed is not correlated with the distribution of the leading edge thicknesses of lye models. A most probable reason for appearance of this structure is the formation of streamwise Goertler type vortices in compression corners.

2. Calculations of the flow around a compression corner have been carried out for various angles of attack (40°, 20° and 0°) in transitional flow regime for different gas models. The calculations have shown that the flow structure, location and shape of the shock wave, distributed and integral aerodynamic characteristics change qualitatively with the angle of attack. The influence of the excitation of internal degrees of freedom on the flow structure and aerodynamic characteristics is most pronounced for the angle of attack 40°. The angle of attack decreasing, the effect of internal degrees of freedom becomes smaller. The effect of free stream nonequilibrium, i.e. increasing the free stream vibrational temperature by factor five, is negligibly small. Besides, in this project we have made an attempt to study the following problems of space debris aerodynamics:
(1) estimation of aerodynamic forces acting on the cloud pieces;

(2) calculation of the pieces motion under the influence of these forces.
It is shown that aerodynamics forces affecting the cloud pieces may have an essential influence on its shape and the trajectory of its movement. They must be taken into account together with gravitational and other forces.

(3) A specialized database HEOPS has been created providing the storage of results of aerothermodynamic experiments and numerical calculations for verification of numerical models and computational methods under development.

Contact

G.E.A. MEIER
Tel.: +49-551-7092177
Fax: +49-551-7092889
Record Number: 24275 / Last updated on: 2000-03-28
Information source:
Collaboration sought: Information exchange/Training
Stage of development: Other