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Rathakrishnan Bhaskaran

Publications and source records attributed to Rathakrishnan Bhaskaran.

Scale Resolving Simulations of Viking '75 Reentry Capsule Wake Flow

Scale resolving simulations of static wake tests of the '75 Viking capsule have been performed using two unstructured grid flow solvers, US3D and PyFR. Simulations with several resolutions have been performed at varying Mach numbers with the aim of solver validation for capsule wake flows as well as establishing simulation best practices.

Rathakrishnan Bhaskaran↗

Scale Resolving Simulations of Viking '75 Reentry Capsule Wake Flow

Scale resolving simulations of static wake tests of the '75 Viking capsule have been performed using two unstructured grid flow solvers, US3D and PyFR. Simulations with several resolutions have been performed at varying Mach numbers with the aim of solver validation for capsule wake flows as well as establishing simulation best practices.

Rathakrishnan Bhaskaran↗

An Assessment of Turbulence Models for MSR Sample Retrieval Lander Aerothermal Design

Several cases from past entries in the T9 and T5 hypersonic test facilities are examined using various turbulence models and shock-layer thermochemistries with the objectives of verifying/validating turbulence models and determining appropriate multiplicative factors on predicted turbulent heating for use in aerothermal design of the heatshield of the Sample Retrieval Lander (SRL) of the Mars Sample Return (MSR) Flagship mission. The zero-equation turbulence models of Baldwin-Lomax and Cebeci-Smith are shown to replicate measurements to within experimental uncertainty for the T9 cases. For T5 cases, the zero-equation model of Baldwin-Lomax can also replicate measurements provided the shock-layer thermochemistry is modified. The modified thermochemistry resolves a dichotomy from past CFD that required different wall catalycity assumptions in the laminar and turbulent flow regimes. The present work shows that such assumptions are not necessary. Finally, an initial estimate for a multiplicative factor on turbulent heating is estimated for the SST turbulence model – the chosen model for SRL aerothermal design simulations.

Mars entry↗

Scale-Resolving Simulations of Viking '75 Reentry Capsule Wake Flow

Scale resolving simulations of static wake tests of the '75 Viking capsule have been performed using two unstructured grid flow solvers, US3D and PyFR. Simulations with several resolutions have been performed at varying Mach numbers with the aim of solver validation for capsule wake flows as well as establishing simulation best practices.

Rathakrishnan Bhaskaran↗

Aerothermal Analysis and Environment Predictions for the Mars Sample Retrieval Lander (SRL)

Mars Sample Retrieval Lander (SRL) is the next mission to Mars, and an integral part of the proposed Mars Sample Return (MSR) Program. Aerothermal Analysis of the SRL capsule takes advantage of the design and analysis of the Mars Science Laboratory and the Mars 2020 missions, findings from the MEDLI and MEDLI2 heatshield instrumentation campaigns, and developments in predictive capabilities over the last 20 years. In particular, SRL is being designed to enter the Mars atmosphere at velocities as high as 8 km/s, which would be the highest for a Mars entry, and is expected to encounter additional shock layer radiation physics compared to previous missions to Mars. This paper presents the status of analysis including the overall methodology, models and assumptions of the aerothermal environment predictions, with a focus on differences from the approaches and modeling used for Mars 2020 and MSL.

Mars↗