A Combined CFD/Material Response Analysis of 3MDCP Arcjet Experiments
The Mars Sample Return Earth Entry System (MSR-EES) project has selected 3-D Woven Mid-Density Carbon Phenolic (3MDCP) as the baseline thermal protection system (TPS) material for the capsule that will return Martian soil samples to Earth sometime in the 2030’s. A series of experiments in the NASA Ames AHF and IHF arcjets will be used to characterize the performance of 3MDCP and to develop and refine material response models for it. The test objectives for these experiments include obtaining in-depth and surface temperature data, mass loss and surface recession measurements, and char depth measurements. To provided pre- and post-test support for the arcjet experiments, a combined CFD/material response was performed using the DPLR and Icarus code. Pre-and post-test analysis on the 3MDCP arcjet experiments was performed using the DPLR CFD and Icarus material response codes. The codes were not tightly coupled, but boundary condition data required by Icarus (e.g., heat transfer coefficients and surface pressures), were extracted from the CFD solutions. This poster shows comparisons between DPLR/Icarus and the experimental data taken during arcjet experiment AHF-348 where 4-inch diameter iso-q models made from 3MDCP were tested in the 12-inch nozzle of the AHF arcjet. This poster also includes a top-level overview of the CFD/material response arcjet simulation process. Best-practices for running CFD solutions of arcjet experiments including how to determine the inflow conditions for the CFD solution from the arc heater settings are discussed. The required inputs to the material response solver are presented, as well as a discussion of how they can be extracted from the CFD solution.