Multidimensional Unstructured-Grid Liquid Rocket Engine Nozzle Performance and Heat Transfer Analysis

Abstract

The objectives of this study are to conduct a unified computational analysis for computing the design parameters such as axial thrust, convective and radiative wall heat fluxes for liquid rocket engine nozzles, so as to develop a computational strategy for computing those design parameters through parametric investigations. The computational methodology is based on a multidimensional, frOte-volume, turbulent, chemically reacting, radiating, unstructured-grid, and pressure-based formulation, with grid refinement capabilities. Systematic parametric studies on effects of wail boundary conditions, combustion chemistry, radiation coupling, computational cell shape, and grid refinement were performed and assessed. = heat capacity = diffusivity = total enthalpy = static enthalpy = radiative intensity = thermal conductivity = turbulent kinetic energy = nondimensional pressure = nondimensional heat flux = recovery factor = location coordinate = nondimensional temperature = law-of-the-wall temperature = time, s = mean velocities in three directions = wall friction velocity = nondimensional Cartesian coordinates = turbulent kinetic energy dissipation rate = energy dissipation contribution = absorption coefficient = viscosity = turbulent eddy viscosity (=pC,k%) = turbulent kinetic energy production = density = turbulence modeling constants = shear stress = direction vector. !2-denotes the leaving radiative intensity direction = chemical species production rate

Computational Analysis of Diffuser Performance for Subsonic Aerodynamic Research Laboratory Wind Tunnel

“…An example of such a complex problem was a study in which the calculation of the axial thrust, convective and radiative wall heat fluxes for liquid rocket engine nozzles was analyzed using CFD. In this study, an unstructured grid was used over a previously designed structured grid due to increasing requirements for parallel computing efficiency and the need for faster grid generation (Wang, 2004). To briefly describe the design philosophy for the ANSYS FLUENT meshes, the solid bodies, that is, the outer diffuser and fan duct wall and the engine nacelle and support spars, had a "face sizing" mesh control applied to their surfaces, with a slow smoothing method applied to the domain from these locations.…”