Cooling Channel Analysis of a LOX/LCH4 Rocket Engine Demonstrator

A computational procedure able to describe the coupled hot-gas/wall/coolant environment that occurs in most liquid rocket engines is presented and demonstrated. The coupled analysis is performed by loose coupling of the two-dimensional axisymmetric Reynolds-Averaged Navier-Stokes equations for the hot-gas flow and the conjugate three-dimensional model for the coolant flow and solid material heat transfer in the regenerative cooling circuit. The latter model is in turn based on the coupled Reynolds-Averaged Navier-Stokes equations for the coolant flow and Fourier equation for the thermal conduction in the solid material. In this study, the thermal behavior of a regeneratively cooled oxygen/methane engine demonstrator is analyzed in detail. Starting from a nominal operative condition of the engine, different levels of channel surface roughness and coolant mass flow rate are considered in order to understand their influence on the heat transfer capability of the cooling system. Results show that the heat transfer can be markedly impaired if the operating parameters undergo rather minor changes with respect to the nominal condition

Implementation of a Parallel Algorithm on a Distributed Network

The objective of this research is to investigate the potential of using a network of concurrently operating workstations for solving large compute-intensive problems typical of Computational Fluid Dynamics. Such problems have a communication structure based primarily on nearestneighbour communication and are therefore ideally suited to message passing. The implementation of a 3-D NavierStokes code on a network of IBM RISC/6000's is described. The performance of this code is compared with that on conventional high-performance machines such as the CrayYMP and the Intel iPSC/860. The results suggest that a cluster of workstations presents a viable and economical resource for this purpose. Additionally a workstation network has the advantage of easy accessibility, fault tolerance and a simple environment for program development

Analysis of Curved-Cooling-Channel Flow and Heat Transfer in Rocket Engines

Coolant-flow modeling in regeneratively cooled rocket engines fed with turbomachinery is a challenging task because of the high wall-temperature gradient, the high Reynolds number, the high aspect ratio of the channel cross section, and the curved geometry. In the present study, to better comprehend the role of the thrust-chamber shape of a rocket engine on the heat exchange, computations of supercritical hydrogen flow in single- and double-curvature channels are carried out. In particular, a parametric numerical analysis of the flow in an asymmetrically heated rectangular channel with a high aspect ratio and various radii of curvature is performed by means of a Reynolds. averaged Navier Stokes solver for real fluids, which is validated against experimental data of heated and curved. channel flow taken from open literature. Results permit the effect of curvature on global heat transfer coefficient, pressure loss, and bulk temperature increase to be quantified