Coupled Heat Transfer Analysis in Regeneratively Cooled Thrust Chambers

Abstract

The coupled hot-gas/wall/coolant environment that occurs in regeneratively cooled liquid rocket engines is studied by a computational procedure able to provide a quick and reliable prediction of thrust-chamber wall temperature and heat flux as well as coolant-flow characteristics, like pressure drop and temperature gain in the regenerative circuit. The coupled analysis is performed by means of a CFD solver of the Reynolds-Averaged Navier-Stokes equations for the hot-gas flow and by a simplified quasi-2D approach, which widely relies on semi-empirical relations, for the coolant flow and wall structure heat transfer in the cooling channels. Coupled computations of the Space Shuttle Main Engine Main Combustion Chamber are performed and compared with available literature data. Results show a reasonable agreement in terms of coolant pressure drop and temperature gain with nominal data, whereas the computed wall temperature peak is closer to hot-firing test data than to the nominal value

Development of Thrust Chamber Components for a System Analysis Tool

“…9. The obtained results are compared with those reported in [9], referred to as "Betti et al", and [11], referred to as "Wang and Luong". The selected roughness value for the milled channel in copper-base alloy is 0.23 µm, this value is chosen for consistency with the results showed in [9].…”

“…In this frame the CFD is used to compute the hot gas side properties, while walls and coolant flow modelling is left to EcosimPro. Coupling is made according to the iterative procedure proposed in [9] which includes the following steps: 1. A first CFD computation is conducted with an adiabatic wall boundary condition for the Combustion Chamber.…”

“…This approach is also referred to as "zooming" and some encouraging results have already been obtained for EcosimPro in the analysis of hydraulic subsystems [10]. The computations carried out for the MCC SSME with the zooming approach is then compared against similar approaches [9,11] available in open literature.…”

“…In the second part the thrust chamber will be coupled with the cooling channels and a heat transfer problem for the SSME will be faced. Aside of this analysis, results obtained with an iterative procedure [9] to couple EcosimPro and high fidelity CFD codes is presented. In order to overcome the inherent limitations of semi-empirical correlations describing the hot gas side heat transfer coefficient, the combustion chamber component will be replaced by a two-dimensional axial-symmetric CFD model of the MCC and connected with the presently available cooling channel component.…”

“…The CFD computations are carried out with the same strategy and solver presented in [9]. The solver is an inhouse three-dimensional multiblock finite-volume RANS equations solver, second-order accurate in space, able to treat multicomponent mixtures of thermally perfect gases.…”