|
[Sponsors] |
April 21, 2013, 10:09 |
[CFD++] problems for transient computations
|
#1 |
New Member
Tomhanq
Join Date: Apr 2013
Posts: 1
Rep Power: 0 |
Hi everybody,
I need some advises to compute a flow in a turbine design. What is quite special is that i'm trying to perform an supersonic oscillating flow at the inlet. So we are in unsteady conditions. - Here is the Bc's at the inlet: BC group:inflow/outflow BC subgroupe: special - oscillatory inflow/outflow (prescribed velocity) This is a flow oscillating (sinusoidal) around 1888 m/s, with a frequency of 1s, an amplitude of about 20 m/s. - Concerning the time integration panel: I'm using a restart file (a steady computation for a flow velocity of 1888 m/s), a transient simulation, implicit integration type. The problem is that I get a complete unconverged solution: very important mass flows (like 2 tons/s!!). I have several possible solutions: - too big time step: it seems to be not better - too much unstable flow: that's why i used a small amplitude - better to play with the CFL: in an implicit scheme, does the CFL have an influence? what i don't understand exactly is the process used by CFD++ for an unsteady computation: time and space discretization, what's going on exactly for each time step. Maybe can u help me, or give some advices or ideas to resolve my problem? thank you all! |
|
April 23, 2013, 09:25 |
|
#2 |
New Member
Mi Baigang
Join Date: Mar 2013
Posts: 11
Rep Power: 13 |
hi,i want to know where can i download CFD++ software?thanks
|
|
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
[ICEM] Problems with coedge curves and surfaces | tommymoose | ANSYS Meshing & Geometry | 6 | December 1, 2020 11:12 |
Needed Benchmark Problems for FSI | Mechstud | Main CFD Forum | 4 | July 26, 2011 12:13 |
Two-phase air water flow problems by activating Wall Lubrication Force | challenger85 | CFX | 5 | November 5, 2009 05:44 |
unstructured grid | sreekanth | Main CFD Forum | 1 | August 6, 2001 15:09 |
Inverse problems | Aleksey Alekseev | Main CFD Forum | 0 | May 12, 1999 15:38 |