Unsteady High-Order Simulation of a Liquid Oxygen/Gaseous Hydrogen Rocket Combustor

Abstract

Coupled Euler-Lagrange simulations are performed for a subcritically operated model rocket combustor at 10 bar pressure (MASCOTTE A-10 test case). A Lagrangian spray model is used to simulate the liquid phase. This liquid oxygen/gaseous hydrogen single element combustor experiment has been the focus of many numerical studies. In contrast to previous investigations, time-accurate unsteady Reynolds-averaged Navier-Stokes simulations are performed. A good spatial resolution is achieved by using a fifth-order multidimensional limiting process scheme to discretize the inviscid fluxes. Instead of assuming axisymmetry, the three-dimensional geometry of the rectangular combustor is taken into account. However, only a quarter of the combustor is simulated, to limit the computational cost. Presented results indicate that three-dimensional effects are important, questioning the assumption of axisymmetry. A second important finding is that time-averaged unsteady Reynolds-averaged Navier-Stokes results agree much better with experimental data than those of a comparable steady-state simulation. Close to the injector, results show a strong unsteadiness of the turbulent flame, which has been observed in the experiment, too. Finally, pressure fluctuations are monitored at several positions in the combustor and analyzed by fast Fourier transform. The peak amplitudes in the pressure spectra could successfully be assigned to the first longitudinal acoustic mode and its higher harmonics.

Numerical Simulations of a Single Injector Gaseous Methane Rocket Combustion Chamber

“…Results from previous simulations 10,11 and other groups 7,12,31,32 suggest that steady simulation cannot correctly model all the occurring features of the strongly unsteady flow field in single injector rocket combustion chambers. Due to the finer computational grids and the required averaging of the solution, unsteady simulations are not feasible for most industrial applications.…”

“…TASCOM3D has been used for simulations of reacting [13][14][15][16][17] and non-reacting [18][19][20][21] sub-and supersonic flows as well as rocket combustion chamber simulations. 10,11 The three-dimensional compressible Navier-Stokes equations are…”

“…10 The rectangular chambers' recirculation zones have a different structure. 11 Figure 13 visualizes the recirculation zone via stream traces in two different planes. Figure 13 a) shows the symmetry plane (z=0) and Fig.…”

“…There is no common opinion whether rocket combustion chambers can be simulated using steady state techniques (RANS) 8,9 or if unsteady methods are required (URANS/LES). [10][11][12] In this paper a methane rocket combustion chamber is studies which has been investigated experimentally at the Technische Universität München. In comparison to the PennState Perburner Combustor 1,4 where only wall heat flux data is available for comparison with numerical results, the experimental measurements also include wall pressures which are used as a second validation parameter.…”

Numerical Investigation of Gaseous Hydrogen and Liquid Oxygen Combustion under Subcritical Condition

“…1, the κ−ε standard, Burke et al, 59 and compressible format of the ideal gas equation of state are performed. Details of the H 2 /O 2 24,27,28,31,33,34,36,44,53 with CARS measurements from ref 55. 4.…”