Perturbation to a Steady State Solution, how to?
Hey all!
So I am modelling a simple Laminar 2D Pipe flow in Fluent, (which I am new to btw). So, once I solve for the transient case for a certain timesteps and I get more or less a steady state solution, I want to introduce a pressure perturbation at the inlet and wanna gauge the response of the fluid. How can I go about doing this in Fluent? Kindly suggest a simple method for this. Regards. |
introducing a perturbation
Hello,
If you want to introduce a perturbation by changing the boundary condition, I would suggest you use a UDF. The following is a code which you can save as a .c file and compile in FLUENT /* the following UDF imposes a value of pressure p0 at the required boundary before time t1. Once t1 is crossed the this a perturbation is introduced in the form of an increased pressure, p1, at the boundary. This is done using an if-else condition */ #include "udf.h" DEFINE_PROFILE(unsteady_pressure, thread, position) { face_t f; real t = CURRENT_TIME; real t1 = 0.1; /*The time after which you want to add the perturbation*/ real p0 = 200; /*This is the initial pressure you impose at the boundary*/ real p1 = 210; /*This the perturbed value of pressure*/ begin_f_loop(f, thread) { if(t<t1) { F_PROFILE(f, thread, position) = p0; } else { F_PROFILE(f, thread, position) = p1; } } end_f_loop(f, thread) } |
you may search online how to add a UDF to FLUENT
|
All times are GMT -4. The time now is 02:23. |