[night-hawk]

Hi Everyone,


I am doing a simulation with MRF. Simulation must run up to 10s . Does setting end time = 10 in controlDict works? For PimpleFoam it is easy to understand this thing. But in simplefoam what does it mean?

[Yann]

Hi,

Since simpleFoam is a steady solver there is no notion of time, but only a number of iteration. So basically timeStep is 1 and endTime is the maximum number of iterations you want to run. (lets say, 2000)

But you can set timeStep to 0.1 and endTime to 200, it will be exactly the same (it will run 2000 iterations)

Saying "Simulation must run up to 10s" does not really make sense with a steady solver.

Keep in mind OpenFOAM is coded to be very generic so controlDict is meant to deal with time and timesteps despite those names are not really relevant for the specific case of steady solvers.

I hope this helps,
Yann

[night-hawk]

Originally Posted by Yann

Hi,

Since simpleFoam is a steady solver there is no notion of time, but only a number of iteration. So basically timeStep is 1 and endTime is the maximum number of iterations you want to run. (lets say, 2000)

But you can set timeStep to 0.1 and endTime to 200, it will be exactly the same (it will run 2000 iterations)

Saying "Simulation must run up to 10s" does not really make sense with a steady solver.

Keep in mind OpenFOAM is coded to be very generic so controlDict is meant to deal with time and timesteps despite those names are not really relevant for the specific case of steady solvers.

I hope this helps,
Yann

What about simpleFoam with MRF? If I apply rotation using MRF with simpleFoam.

[Yann]

I am sorry but I am not sure to understand your question, using MRF or not does not make a difference for what is written in my previous post.

MRF is a steady state method to model rotating objects, there is no mesh or part motion. (You could not use a transient modeling technique in a steady solver framework anyway)

Yann

[night-hawk]

Originally Posted by Yann

I am sorry but I am not sure to understand your question, using MRF or not does not make a difference for what is written in my previous post.

MRF is a steady state method to model rotating objects, there is no mesh or part motion. (You could not use a transient modeling technique in a steady solver framework anyway)

Yann

Thanks for your reply, My confusion was if I do simulation with pimpleFoam + MRF and take it readings after it becomes steady and doing same simulation with simpleFoam + MRF will answer be different?