Currently I am using snappyhexmesh for experimenting with inflation layers on this flow past cylinder. What other open source tools can I use to build them for complex geometries? In our opinion is snappy enough for complex industrial geometries?
Does anyone specifically know of good books/papers which deal with the issue of how specifically bad cells behave and how does one test them. I am trying to improve my code. Currently I just limit the pressure gradient in bad cells and it works but the approach is a bit arbitrary. I am a bit perplexed on how exactly does one design tests for bad cell behaviour, some theory on bad cells and how one could improve solvers to make a fairly good use of them
Back to the problem I posted previously: judging GPU speedups. I am reading all sorts of stuff on MIUPS. I am testing my unstructured solver on a single A100 and I get close to 50 for double precision for the full solver and about 100 for the pressure solver alone. Fp32 is about 1.5x faster. How does one judge a benchmark from the internet for steady SIMPLE? I get all kinds of values from 50 to 100+for an A100. Are these mixed precision? They never mention. If the problem allows me to solve small inexact solves the steady SIMPLE can manytimes converge well with single precision, so isn't there a proper benchmark for this?
I was running a sine-wave like MMS on unit cube on a Stokes like solve ok polyhedral mesh using SIMPLE. The bcs are zero dirchlet on the cube walls and zero gradient for pressure Poisson. Initially I ran this on my code and velocity always converged with second order but pressure convergence was suboptimal with values like 0.5 which grow as I refine but velocity always converged well at 2. Adding orthogonal correctors did not help much. I used Rhie chow based collocated grid here. I thought this was a bug. So I ran the same on OpenFOAM and I was surprised to get the same behaviour. Am I doing something wrong or is the zero gradient BC causing weird behaviours för convergence
When I do run both OF and my code on simple laminar cases which I am investigating I get similar pressure drops say in a pipe for such cases. So is this due to the operator split or the SIMPLE approach?? Because previously when I wrote FEM codes I always solved the full saddlepoint problem and MMS converges cleanly in both pressure and velocity. I never used SIMPLE like scheme for convergence tests then. Am I just lucky to get the pressure values close to correct in pipe or other geometries?
