Some remarks on the CFD research for space transportation system development

The effort by the CFD researchers in aerospace community has mainly focused on flow simulations over more and more complex body configurations and their flow physics. It is true that we should continue such effort but there are other types of research that may make the CFD to be a real useful tool in aerospace engineering. Two of the research examples in our group are presented as such examples. One example is the flow simulations of the flow fields over SSTO-type reusable launch vehicles configurations. Conventional RANS model, with the conventional turbulence model under relatively coarse grid distributions is intentionally used. The issue here is the establishment of reliability of the conventional CFD tools and the accumulation of CFD database based with the confident reliability. The result indicates that the conventional method can be used for wide range of flow speeds and pitch angles with a small care for side-wall flow separations. Second example is the simulations for the supersonic base flows. Estimation of base pressures is important for most of the space transportation vehicles. LES/RANS hybrid method is used with sufficient grid resolution of the wake flow field. The result shows the accuracy and reliability of the method. The LES/RANS hybrid method may replace many of the RANS simulations and can be a, practical simulation tool in a few years. The present paper shows that CFD researchers have to reconsider the real needs from outside CFD community and there are many types of research opportunities available in CFD.