Hello community,
I'm working on a CHT atmospheric reentry simulation to analyze temperature distribution, and I continue to receive errors from chtFlowRegionPimpleFoam despite trying several solutions.
Project Configuration:
Analysis: Conjugate Heat Transfer
Velocity: 7500 m/s, but decomposed into its Cartesian components because I want it to re-enter at a 10º angle (hypersonic flow, ~Mach 22)
Current Temperatures:
• Ambient: 295 K
• Capsule and Initial Flow: 350 K
Mesh: 16,451 volumes, quality compliant
Configurations tested:
Reduced relaxation factors (0.3-0.7)
Non-orthogonal correctors: 4
Absolute pressure: 101325 Pa in boundary and initial conditions
Compressible flow enabled
Problem:
The solver keeps failing with chtFlowRegionPimpleFoam errors. The mesh has good quality and is multi-region, suitable for CHT. Please help. Project link: https://www.simscale.com/workbench/?pid=2610083810083270180&mi=spec%3A2bbe793a-fa79-42c7-b1eb-e7ca0e409392%2Cservice%3ASIMULATION%2Cstrategy%3A13
Hello!
The compressible capability within CHT is pressure-based in nature and, as such, it is not a good option for speeds > 0.7 Mach. As such, I do not think that you would be able to simulate speeds of 7500 m/s with CHT, as the solver is not geared towards that kind of speeds.
Thank you very much Ricardo. So, what do you recommend I do? Should I change the solver for another one? Which one? Speed is one aspect I can’t change due to my simulation goal.
With the solvers available for community users there are no options for transonic/supersonic flow (and beyond).
The only solver that can go transonic/supersonic is “Multi-purpose” (example), however even then you have more than Mach 20, which is quite a lot. With multi-purpose I typically see cases with speeds between Mach 0 and Mach 5-6~. This solver requires a subscription and is not available for community users, though.
I’ve significantly lowered the speed to 100 ms and I’m still getting the exact same error, so I don’t think the speed is the problem. What other factor could be causing the error?
Hey @Miikee ,
Could you please share the link to your simulation with the lower speed ?
Best,
Satvik 
hey, this is my link of my simulation with the lower speed (100 m/s). SimScale Login
Hey @Miikee ,
Are you sure you saved the reduced velocity before running the simulation, it still shows 4-digit speeds to me:
Best,
Satvik