Multiparameter Optimization of Thrust Vector Control with Transverse Injection of a Supersonic Underexpanded Gas Jet into a Convergent Divergent Nozzle

Abstract

The optimal design of the thrust vector control system of solid rocket motors (SRMs) is discussed. The injection of a supersonic underexpanded gas jet into the diverging part of the rocket engine nozzle is considered, and multiparameter optimization of the geometric shape of the injection nozzle and the parameters of jet injection into a supersonic flow is developed. The turbulent flow of viscous compressible gas in the main nozzle and injection system is simulated with the Reynolds-averaged Navier–Stokes (RANS) equations and shear stress transport (SST) turbulence model. An optimization procedure with the automatic generation of a block-structured mesh and conjugate gradient method is applied to find the optimal parameters of the problem of interest. Optimization parameters include the pressure ratio of the injected jet, the angle of inclination of the injection nozzle to the axis of the main nozzle, the distance of the injection nozzle from the throat of the main nozzle and the shape of the outlet section of the injection nozzle. The location of injection nozzle varies from 0.1 to 0.9 with respect to the length of the supersonic part of the nozzle; the angle of injection varies from 30 to 160 degrees; and the shape of the outlet section of the injection nozzle is an ellipse with an aspect ratio that varies from 0.1 to 1. The computed fluid flow in the combustion chamber is compared with experimental and computational results. The dependence of the thrust as a function of the injection parameters is obtained, and conclusions are made about the effects of the input parameters of the problem on the thrust coefficient.

Fluid Dynamics of Thrust Vectorable Submerged Nozzle

“…The velocity profiles and turbulence properties affect the convective heating loads and potential erosive burning of the propellant. The internal flowfield in SRM is in qualitative agreement with experimental, theoretical, and computational studies in which mean velocity and turbulent kinetic energy fields have been studied [23].…”

Thrust Vectoring of a Fixed Axisymmetric Supersonic Nozzle Using the Shock-Vector Control Method

“…In this section, the analysis based on the fully three-dimensional numerical simulations of the nozzle under SVC forcing is discussed. In previous SVC vectored nozzle studies [19,20,36,38] performances are analyzed and characterized by varying the NPR and the secondary mass flow ratio SMF for a jet-flow efflux in calm air. External flow interactions have been accounted for mainly by CFD approaches in two dimensions [39].…”

Aerodynamic Characteristics of the Novel Two-Dimensional Enhanced Shock Vector Nozzle

“…The primary flow then deflects through this shock wave, altering the vector angle and enhancing vector thrust. The effects of the NPR, secondary pressure ratio (SPR), and geometrical parameters on the performance of the SVC nozzle have been explored by a series of experiments and numerical studies [18][19][20][21][22][23][24][25][26][27]. The vector angle of an SVC nozzle increases monotonously in the absence of shock Due to its straightforward installation and implementation, the shock vector control (SVC) method is readily applicable in engineering practice [17].…”

“…With an increase in the NPR, the primary flow momentum increases, the range and intensity of the high-pressure zone before the secondary flow decrease, and the separation and reattachment even occur after the secondary flow, which leads to a decrease in the thrust vector angle of the nozzle, but the thrust coefficient increases. The jet's position and jet angle are the key geometric parameters [25][26][27]. The jet near the nozzle outlet and opposite to the primary flow is helpful in improving the vector performance of the SVC nozzle with less thrust loss [27].…”