The effective exploration of the outer reaches of our solar system is one of the most important objectives in thevarious space programs of the world. One of the more interesting objectives of such an exploration is a robotic spaceprobe mission to Titan. There are various observational data to suggest that Titan may hold the key to various keyraw elements and this can be varied with a mission that has an objective of a successful re-entry to Titan'satmosphere. A typical probe for Titan's entry with forward facing axisymmetric cavity is investigated numerically forpeak heat fluxes using commercially available Computational Fluid Dynamics code Ansys Fluent 13.0. The cavitiesinvestigated are circular in shape with rounded lips while the lip radius is varied from 20 cm to 80 cm. The Martianentry vehicle chosen for the simulation is 60-deg sphere cone probe with a projected diameter of 2.7m and noseradius of 1.25 m. The flow conditions simulated in the investigation are that of ballistic descent through the Titan'satmosphere with free stream Mach No., pressure and density of 18.86, 15.62 Pa and 0.000296 kg/m3 respectively. Atwo dimensional axisymmetric computational fluid dynamic analysis is done for ideal gas condition and will beextended to non-equilibrium chemically reacting gas assumptions with non-catalytic wall in the further study. Thenon-equilibrium chemistry is simulated using thirteen species with 24 step reaction of Gokcen. The presence of largecavity at the nose is likely to reduce the maximum heating rates at the stagnation region which is extremely desirablefor safe delivery of payloads. It is the objective of this paper to ensure to suggest relevant design parameters for asuccessful reentry mission to Titan so that it can set the trend for similar missions in the future.
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