Experimental studies of acoustic effects of propulsive landing system jets on reentry vehicle of crew transportation spacecraft

The paper presents results of model-test studies of acoustic effects on the surface of the reentry vehicle of jets from vertical and horizontal braking nozzles of solid rocket landing engines of the advanced crew transportation system reentry vehicle. The experimental studies were run in an anechoic box of the differential nozzle testing facility the Keldysh Center at 60...120 kg f/cm2 full pressure of working medium upstream of the nozzles, using high-temperature combustion products of air-ethanol propellant and cold air. The experimental studies were run using a landing surface mockup on a 1:7 scaled model of the reentry vehicle, which had all the nozzles of the propulsive landing system, as well as on a 1:1,5 scaled model of a single vertical braking nozzle with adjustable throat section and a mockup of a fragment of the aft section of the reentry vehicle. The obtained experimental data were scaled up to full-size conditions, which was necessary to determine the acoustic environment inside the crew cabin of the reentry vehicle and vibrations induced by the external acoustic field and acting upon the hardware and avionics components of the reentry vehicle.