The aerodynamic characteristics of a supersonic rocket-sled with multi-facilities on the ground

Described in this paper is an investigation on the aerodynamic characteristics of a full-scale realistic supersonic rocket-sled in operating conditions. The scale adaptive simulation (SAS), coupled with the layer dynamic mesh method, as well as a rocket-sled test, is employed here to present the detailed aerodynamic characteristics. The method used, overcoming the disadvantages of the wind tunnel test and the numerical blowing method, presents the realistic aerodynamic characteristics of an operating rocket-sled. Considering the realistic geometry, the effects of the sled-beam, supports, rails, fasteners, and sink on the aerodynamic characteristics of a supersonic rocket-sled are systematically studied. The aerodynamic characteristics, in terms of the transient flow structures, momentum transport process, lift and drag force, the aerodynamic characteristic frequency is considered at Mach numbers ( Ma ) of 1.5, 2, 2.5 and 3, while the corresponding test results are obtained at Ma of 1.5, 2, and 2.5. The results found show that the bow shock and compression waves of the rocket-sled are reflected at the multi-facilities, causing the complex wave structures, vortex shedding and aerodynamic characteristics. Compared with the simplified flat ground condition, the increase of 818% in the time-averaged lift of the rocket-sled is induced by the full-scale realistic multi-facilities at Ma = 2. The fasteners on the ground contribute to the increase of the lift, while the rail is not helpful. The sink on the ground produces a dramatically asymmetrical flow field which is revealed by the fraction coefficient and limiting streamlines of the rocket sled surface. In addition, the reflected compression waves are significantly enhanced by the periodically fixed fasteners, resulting in the periodic characteristics of the lift and drag force. The PSD (Power Spectral Density) analysis of the pressure, lift and drag force is employed to illustrate the characteristic frequency. The dominant frequencies of the rocket-sled at Ma = 1.5, 2, 2.5 and 3 are 407.6 Hz, 544.6 Hz, 679.9 Hz and 817.2 Hz, respectively. The results provide a reference for avoiding the resonance between the rocket-sled in operation and the rail.