UDF at pressure inlet[pleas help me!!]
I would like to increase pressure and temperature at pressure inlet boundary.
As like this,
1~1000 iteration : pressure - 101325 pa, temperature - 250K
1001~2000 iteration : pressure - 101325* 2 , temperature - 500K
How do i do complete my goal?
I could compile and hook, but it is all!!
I try to code UDF to find a solution by myself. but it does not work!!
A few things:
1) Are you really trying to change boundary conditions on a per-iteration basis? Is this a steady state or a transient problem? If you're actually trying to do a steady state simulation and you want to change inlet conditions after a specified number of iterations, don't. Simply put your boundary conditions to what you want them to be at t=infinity and let the simulation solve.
2) If you're trying to solve a transient case, and by iterations you mean "time steps" or "simulation time, in seconds" have a look at this Time dependent flows in Fluent with UDFs
3) Finally, more of a numerics issue...The changes you're imposing are fairly dramatic over what, presumably, will be a short period of time. This often causes convergence difficulties, and rightfully so -- the physics you're trying to impose are almost non-physical. In one timestep (very short) the pressure and temperature across an entire face double. Typically, one would impose a slightly more gentle ramp than a step change, and take fractional timesteps in the "in between" part to allow the solver to get to a more stable answer.
I hope this helps!
I refer your opinion for the model.
So, I use the below code for pressure and temperature.
For pressure code, I hook to Gauge total pressure and for temperaturee code, to temperature.
Next, I set the time step size = 0.001 and number of time steps = 10000
and Max iterations per step = 1. Because I would like to increase the pressure at 1013250 and the temperature at 2500K after all calculating.
Is it OK what I thought to be?
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