Angular injection of hydrogen fuel in a scramjet combustor is explored numerically. Three-dimensional Navier–Stokes equations with turbulence and combustion models are solved using commercial computational fluid dynamics software. Both infinitely fast kinetics and single-step finite rate H2–air kinetics are used to find out the effect of chemical kinetics in the thermochemical behaviour of the flow field. Grid independence of the results is demonstrated and gridconvergence index-based error estimate provided. k- ω turbulence model performs better, in comparison to k– ϵ and shear stress transport models, in predicting the surface pressure. Single-step finite rate chemistry (SSC) performs extremely well in predicting the flow features in the combustor. Computed temperature and species mole fraction and wall pressure distributions with SSC match better with the experimental results compared to fast chemistry calculation and detailed chemistry calculation of other workers. It has been observed that simple chemistry can describe H2–air reaction in scramjet combustor reasonably well.

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Numerical simulations are performed to characterize the jet vane thrust vector control mounted in the rear of a rocket motor. The three-dimensional Navier—Stokes equations along with the K—ε turbulence model are solved in a hybrid mesh consisting of an unstructured grid and a structured grid. All essential flow features including the complex compression/expansion wave interactions emanating from the vane surfaces and shrouds are captured by simulation. The computed side force coefficients are seen to vary linearly with chamber pressure and vane deflection angles. A theoretical correlation has been developed by a non-linear regression analysis from the computational fluid dynamics (CFD) database to predict the force and moment coefficients for different chamber pressures, vane deflection angle, and roll offset angle. The theoretical correlation compare very well with full CFD simulation as well as the experimental data.

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