Measurements and modelling of wall heat fluxes in rocket combustion chamber with porous injector head

Kurzfassung

A rocket combustion chamber with a porous injector head, which is a new concept for injecting propellants, is tested. The hot-fire tests are carried out using cryogenic oxygen and hydrogen at the mass ratio of oxidizer to fuel of 6 and at pressure of 80 bar. Pressures, wall temperatures, and wall heat fluxes are measured along the axis of the chamber. The wall heat fluxes are determined by the calorimetric method. The wall heat flux has a maximum at a distance of 50–100 mm from the injector plate. To interpret the experimental results, numerical simulations are performed using the commercial CFD code ANSYS CFX. The turbulent flow is modelled by the Favre-averaged Navier–Stokes equations and the shear-stress transport model. The turbulent combustion is modelled using two different models: the extended eddy-dissipation model and the extended coherent flame model. Results obtained with the different models are compared both with experimental data and with each other. The numerical results agree with the experimental data. The extended eddy-dissipation model gives the very good agreement which is achieved by applying additional parameters (‘Flame Temperature’ and ‘Extinction Temperature’) dependent on the mixture fraction.