Computational fluid dynamic analyses of multidimensional combustion instabilities in liquid rocket engines are presented. A hierarchy of solution procedures is developed to synergistically investigate possible contributing physical phenomena in a systematic and efficient manner. The various computational approaches are demonstrated to accurately capture both spinning and standing wave motions with a minimum of amplitude and phase errors. Both collapsed and distributed combustion response functions are considered as driving mechanisms of the instability process, and are related to commonly employed droplet vaporization models by a local velocity and pressure linearization. This formulation permits the coupling of both analytical and numerical solution procedures to study the effects of distributed vaporization on stability behavior. The simplified distributed vaporization analysis utilizing the various vaporization models for uniform droplet temperatures appears to predict stable transient behavior over a wide range of conditions, although additional research is required to relax some of the governing assumptions The impact of additional effects can be tested by comparing the results from each of the solution methodologies. The present results for both collapsed and dstiributed combustion response demonstrate that the numerical approaches represent a validated testbed upon which more realistic modelling of physical processes can be included. Current research is directed at incorporating more detailed physical models for the important liquid phase processes and assessing their individual impacts on combustion instability.
Three-dimensional analysis of combustion instabilities in liquid rocket engines
3-dimensionale Untersuchung über die Verbrennungsinstabilität in Flüssigtreibstoff-Raketentriebwerken
AIAA-Papers ; 1-14
1993
14 Seiten, 12 Bilder, 11 Quellen
Conference paper
English