Numerical Studies on Thrust Augmentation in High Area Ratio Rocket Nozzles by Secondary Injection

Abstract

Single stage to orbit propulsion devices are being developed as part of low cost access to space endeavors. Sea level operation of high area ratio rocket nozzle used in rocket engines leads to an overexpanded flow condition resulting in high side loads. Secondary injection of propellants in high area ratio nozzle is an attractive option to overcome the inefficiency of operation of such nozzles in sea level conditions in addition to the augmentation of thrust. A numerical study on thrust augmentation in high area ratio nozzle by secondary injection of propellants is presented here. The turbulent compressible reacting flow in rocket nozzle with auxiliary injection is simulated using conservation equations for chemical species based on finite rate chemistry model and compressible Navier-Stokes equations with AUSM+-up upwind scheme based unstuctured finite volume solver. An optimized eight step, six species reduced H2-O2finite chemistry reaction model is used to model the supersonic combustion. The indigenously developed solver has an efficient rescaling algorithm to alleviate the effect of stiffness in conventional explicit algorithm for simultaneous solution of reacting flow. The code is validated using the wall pressure and hydrogen concentration values reported for the similar high area ratio rocket nozzle. Accurate prediction of nozzle performance is possible with present turbulent reacting flow simulation as it take care of all losses in nozzle flow. Extensive computations have been performed for the performance estimation of high area ratio rocket nozzle for various prospective auxiliary injection options.

Experimental and Numerical Studies of Secondary Injection in Nozzle Divergence for Thrust Augmentation

“…The nature of flow features and shock interactions are well understood for a jet issuing into a free stream supersonic flow and an expanding supersonic flow (Shyji et al 2017;Candon & Ogawa 2015). Figures 6 and 7 show the experimental and numerical schlieren images for the conditions 15_4CF_2Inj and 30_3CF_2Inj (see Table 1).…”

“…The objective of this work is to get a theoretical understanding of the JICF phenomenon for a supersonic flow from a simple flat plate injection and extending it to an expanding supersonic flow. The simulation study conducted by Shyji et al (2017) is used as a reference for understanding the salient flow features in a diverging nozzle. To understand the flow features and performance parameters, the methodology adopted in the present study involves experimental and numerical approaches.…”

Modeling of Erosion Wear of Sand Water Slurry Flow through Pipe Bend using CFD

“…Some of these models are given by (Finnie et al 1960, Bitter et al 1963, Neilson and Gilchrist et al 1968, Huang et al 2008, Oka et al (2005, Zhang et al 2007) and others through experiments. During the last few years, design and performance analysis of fluid mechanics have experienced great progress with the availability of less expensive high performance computers and user friendly computational fluid dynamics (CFD) software's (J.P. Singh et al 2017, S. Shyji et al, 2017, E. Shirani K. et al, 2011, Talbi et al, 2009, A. Ababaei et al, 2017. (Zhang et al 2000) have studied the erosion and corrosion in the pipe using glass particles in CFD with the Lagrangian particle track model.…”