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-   -   Influence of initialize on the steady-state solution? (https://www.cfd-online.com/Forums/fluent-udf/152888-influence-initialize-steady-state-solution.html)

aestas May 11, 2015 22:01

Influence of initialize on the steady-state solution?
 
Hello friends, i am now confused about the influence of initialize on the result of steady-state solution

In my supersonic problem, i set a pressure_inlet boundary condition for the inlet, and i calculated the static pressure and stagnation pressure and stagnation temperature for the problem. In order to keep the solution stable, i set 10%of this inputs in the pressure_inlet boundary, and gradually increase them during solution.(And similar method was used for the source terms for all the equation.)

The problem is, i want to initialized the velocity for the inlet boundary, when i used the real vaule(1.1e4 m/s), the solution will quickly become divergence, however, if i used the 10%of the real value, i.e., 1.1e3 m/s, the solution could reach convergence.

i am now confused whether this initialize of inlet velocity could influence the final result? In my opinion, the inlet boundary condition relays on the real inlet velocity (through Mach number), so the initialization is just to make the solution easy to reach convergence, but i donot know whether this is right or wrong?:confused:


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