solution running slow

Tushar_Telmasre · July 2, 2017, 13:38

Dear all,
I set a simulation in fluent with solidification model and VOF model. First I used a rectangular domain and the solution I got was fine and quick. After completing that I set up the same physics and the same models and same boundary conditions, but now using a Trapezoidal Geometry. here I am getting the iterations are sluggish. The simulation is taking forever to run.

What can be the reason? Same physics and boundary condition are giving me very different solution times, the only difference being the rectangular and trapezoidal geometries.

I think, it is because of the difference between mesh elements. In rectangular geometry all the elements are rectangular and in trapezoidal geometry the elements are combination of rectangular and triangular elements. well, If that is the case how to solve the problem?

Using system
Intel core - i7 6th generation
16Gbs of RAM
no Graphics card

bhargavbharathan · July 18, 2017, 13:33

Hi,

Did you run a grid independence test? Check the results from various mesh sizes and see how your desired parameters change.

How much change are you actually expecting in the results between the two models? Do the results so far match or is the issue just the run time?

-BB

July 2, 2017, 13:38	solution running slow	#1
Tushar_Telmasre Member sebastian bergman Join Date: Mar 2017 Location: seattle Posts: 52 Rep Power: 9	Dear all, I set a simulation in fluent with solidification model and VOF model. First I used a rectangular domain and the solution I got was fine and quick. After completing that I set up the same physics and the same models and same boundary conditions, but now using a Trapezoidal Geometry. here I am getting the iterations are sluggish. The simulation is taking forever to run. What can be the reason? Same physics and boundary condition are giving me very different solution times, the only difference being the rectangular and trapezoidal geometries. I think, it is because of the difference between mesh elements. In rectangular geometry all the elements are rectangular and in trapezoidal geometry the elements are combination of rectangular and triangular elements. well, If that is the case how to solve the problem? Using system Intel core - i7 6th generation 16Gbs of RAM no Graphics card

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July 18, 2017, 13:33		#2
bhargavbharathan Member Bhargav Bharathan Join Date: Jun 2015 Location: Montreal, Canada Posts: 71 Rep Power: 11	Hi, Did you run a grid independence test? Check the results from various mesh sizes and see how your desired parameters change. How much change are you actually expecting in the results between the two models? Do the results so far match or is the issue just the run time? -BB