MODELING OF A SOLID-FUEL COMBUSTION-CHAMBER OF A RAMJET USING A MULTIBLOCK DOMAIN DECOMPOSITION TECHNIQUE

A computer code aimed at the simulation of the physical phenomena occu ring in the solid fuel combustion chamber of a ramjet was extended to accommodate multi-block grids. The mathematical model is based on the numerical solution of the governing equations for mass, momentum, ener gy and transport equations for scalar quantities. The k-epsilon model and the conserved sealar/prescribed probability density function forma lism are employed. Heat and mass transfer at the walls are calculated using the wall functions of Chieng and Launder modified to account for porous walls. The multi-block method allows discontinuous grid lines along the interblock boundaries and transfer of data between neighbour ing blocks satisfies flux conservation. The implementation of the mult i-block domain decomposition technique is demonstrated for a turbulent isothermal flow through a pipe with a sudden expansion and for a soli d fuel combustion chamber of a ramjet. In this case, the evolution of the local regression rate along the wall is in good qualitative agreem ent with the data, but quantitative disagreement was found, mainly due to the shortcomings of the turbulence model employed. (C) Elsevier, P aris.