Simulation of the Bypass Dual Throat Nozzle and investigation of parameters affecting the change of thrust vector angle

Abstract

A new method for controlling the thrust vector is the use of Bypass Dual Throat Nozzle (BDTN). The aim of this study was to investigate the effects of three parameters including secondary flow injection angle, secondary flow injection location and bypass section geometry on the deflection angle of the thrust vector. The model is simulated in both two and three dimensional for a Dual Throat Nozzle. The results show that by increasing injection angle of the secondary flow, the deflection angle of the thrust vector decreases by about 27%. Also, by placing the location of secondary flow injection after the throat, we can see the deviation of the thrust vector angle is more than the flow injection before the throat. The largest difference between the injection mode in the throat and the injection after the throat is about 25% and the largest deviation of the thrust vector angle occurred at an angle of 45 degrees at the injection position in the throat. Also, in three-dimensional simulation, three cross sections (rectangular, square and circular) with the same area for the bypass channel were compared in terms of the deviation of the thrust vector angle. In this study, the canal with rectangular cross section in most cases has deviated about 3.7% more than the circular cross section of the thrust vector angle.