NUMERICAL RESEARCH OF REDUCTION OF ACOUSTIC WAVES INTENSITY AT INTERACTION OF TWO-PHASE CLOUDS WITH ACOUSTIC EMISSION OF ROCKETS JETS AT SPACE ROCKET START

摘要

The most effective way of decrease of acoustic loads acting on a payload of space rockets at start is creating a dispersed water drop cloud in the area surrounding a jet of a rocket engine and a zone of its interaction with elements of the launch complex. We use both the absorptive effect of the cloud, and the possibility of redistribution of energy of an acoustic field in space, connected with the decrease of propagation rate of acoustic waves in the cloud. The model on the basis of the Helmholtz equation with varied in space coefficients which are taking into account, the non-uniformity of density of a cloud and the spectrum of drop sizes are used for calculation of the interaction of the acoustic field with the cloud. The received system of simple equations is solved by the direct Gauss method. The effective algorithm is developed which makes it possible to reduce the amount of needed computer memory in dozens of times in contrast to the classic algorithm due to the twice increased amount of calculations. For the conditions of mean-scale experiments the calculations are conducted, in which efficiencies of the clouds with different shape, water concentration and drop sizes are compared at different frequencies.