Features of using of centrifugal two-stage jets in the construction of hybrid rocket engines with deep control of thrust

In this paper the example of improvement of hybrid rocket engine for achievement of thrust deep controlling is shown and two-stage centrifugal atomizers of a liquid supply system component were analyzed. Two construction of two-stage centrifugal atomizers were that are intended to implement thrust deep controlling were analyzed and the features of the work of these injectors with the presence of deep-flow control were shown. The efficiency and advantages of two-stage centrifugal atomizers in comparing with regular centrifugal atomizers were shown. The system of equations including the equation of conservation of momentum fluid and continuity equation with closing dependence of flow through the nozzle and the geometrical characteristics were examined. Features of work include changing the angle of spraying in a wide range (60-120°) depending on the operating mode with deep throttling flow through a nozzle, which leads to unstable operation of the engine, namely the unstable combustion, pressure fluctuations and quality of the spraying process. Methods aimed on reducing the range of the angle of the spray on the deep flow control mode were shown. The construction of modernized two-stage centrifugal atomizers with circular groove that are able to reduce the diapason of changing the spraying angle with deep throttling flow through a nozzle were shown. The main conditions for designing of the circular groove were identified, as well as the technique of calculation in the form of a flowchart of the program for calculating the two-step upgraded injectors with a reduced range of variation of the angle of the spray.