Semenenko P. Gasdynamics of Launch Vehicle Payload Fairing Area in Atmospheric Flight Leg

The object is the gas exchange process between air volume of the carrier-rocket fairing and the atmosphere on the transonic flight segment of carrier-rocket. The aim is to determine the laws of pressure change under the carrier-rocket fairing on the atmospheric flight segment taking into account gas dynamic peculiarities of its flowing about as well as its structural parameters. The requirements based on the results of the solution of mass and energy problems in gas flows through non-hermetic system holes and in the holes between the sections under the fairing for various types of aerodynamic arrangement have been formulated for the first time. The observance of them at the stage of carrier-rocket projecting makes it possible to substantiate geometric parameters and the places of drainage holes that satisfy the limitations of pressure decrease rate under the fairing on the transonic flight segment without any ballistic calculations. The numerical algorithm based on the laws of gas-flows motion and their relationship with each other and the fairing has been elaborated. This algorithm makes it possible to determine the quantitative and qualitative flow characteristics through drainage holes. Due to this it is possible to determine geometric parameters and the places of drainage holes on the fairing that provide the minimal values of pressure drop on the transonic trajectory segment under the existence of some non-hermetic systems and the division of the volume under the fairing into the sections connected by holes. There have been worked out the methods for calculating gas dynamic processes parameters in the fairing zone on the atmospheric flight segment as well as the recommendations as to minimization of pressure drop rate under the fairing. The application sphere is educational process, elaboration of drainage system of carrier-rocket fairing.