EFFECT OF GROUND PROXIMITY ON AERODYNAMIC FORCES AND MOMENTS OF REUSABLE LAUNCH VEHICLE AT SUBSONIC SPEED

Abstract

This paper explores the effect of ground proximity on aerodynamics forces and moments acting on reusable launch vehicle at the time of its landing. As the name indicates the concept of reusability is attractive especially in case of Space Transportation and launch vehicles as it reduces the mission cost. The design of Reusable Launch vehicle is also very critical as the vehicle has to pass through various speed ranges from hypersonic to subsonic. RLV wing is generally low aspect ratio double delta wing which is very sensitive to ground effect due to the characteristic excessive vehicle attitudes associated with the landing and touchdown phases of flight.. In present study, a RLV model of 260 mm total length and reference area of 155mm2 had been modeled using CAD tools. It has double delta wing of wing span 144mm and mean chord of 76mm and vertical stabilizer of height 38mm. Effect of ground proximity on aerodynamic forces acting on RLV has been studied using commercial CFD software. During present analysis computational analysis has been done for different height. Height of RLV is varied from free flight condition to landing touchdown height and the angle of attack has been varied for 0 to 20. The complete study is done for lower subsonic speed at Reynolds number of 1.8*106 for fix ground and moving ground conditions separately.