DLR RFZ Reusable Rocket Model in 4.3 Billion cell CFD - FluidX3D on 2x Intel Xeon 6979P

#SC24 day 4! What does it look like when a reusable rocket booster slows down in Earth's atmosphere? I've simulated DLR's RFZ rocket model in #FluidX3D. 2x #Intel Xeon 6979P CPUs chew through this 4.3 Billion cell simulation in ~14 hours! 🔥

Simulation Stats:
- Intel CPU Runtime for OpenCL (oneAPI)
- Lattice Boltzmann (LBM), D3Q19 SRT, FP32 arithmetic, FP32 memory storage
- 1624×1624×1624 = 4.3 Billion grid cells, 1 cell = (2.6 mm)³
- 380 GB memory footprint (55 Bytes/cell, or 19M cells per 1GB)
- 22224 time steps = 0.05 seconds real time
- 3x 1200 4k images rendered, velocity-colored Q-criterion isosurfaces visualized
- 100 m/s airspeed
- Reynolds number = 321M
- Runtime = 13h53m(total) = 7h28m (LBM compute) + 6h24m (rendering)
- Average LBM performance = 3541 MLUPs/s

Hardware Specs:
- 24x 128GB 8800MT/s MRDIMMs, for 3TB total RAM at 1.7TB/s
- 0x #GPU​s

[quentinwach]

Something I always wonder about when I see your simulations: Doesn't the discretization lead to artificially high friction and turbulance around the object? It's just an intuition but if so, how problematic is this and can one do about it?

[InternetListener]

How many chestnuts can you cook with 240 P-cores at 100% Load?

[wills.]

14 hours with 2 of the most powerful processors ever manufactured for this kind of an application to simulate 0.05 seconds of airflow data using cells 866, 666 times bigger than the real resolution of airflow. Pretty mindblowing to think how far we've come in computer simulations, and how much more accurate they can become. 10 years ago you would've needed a supercomputer for something like this

[shubhamnikumbh]

How we can refine a geometry more smoothly for better simulation results? The edges are so rough the airflow disturbed while passing?

[browskie]

HI, Can this cfd do conjectate heat transfer analysis ?

[_John_P]

Have you got any tutorials for the drone model?

[KasimirvonFinck]

Dr. lehmann, I love your work! Cudos all the way, I am using your library and tool in amazement for researching and understanding aviation and it is just exactly my thing. Thank you for the great work.