Hi,all When I initialize an unsteady flow, there is erro info @Error: FLUENT received fatal signal (ACCESS_VIOLATION) 1. Note exact events leading to error. 2. Save case/data under new name. 3. Exit program and restart to continue. 4. Report error to your distributor. Error Object: ()@

What this mean? Anyone can give some help? What are the possible reason for this erro? I can't patch the flow domain.

Thanks for any help

Erica

That error is common when trying to access data that Fluent usually doesn't keep. You can get Fluent to keep the data in memory by typing solve/set/expert and answering yes to the question about temporary memory. Sometimes it is necessary to enter this command and then run a single steady state iteration before setting the problem up in the desired transient form. Hopefully this works for you.

Thank you very much, I'll try next.

Hi,Peter. Thanks for your help. There is another question. I'm doing a case in which I define a mass source depent on the wall temperature. when I intialize the flow field, that error occurs. I wonder whether there are any other reason for it or not? The UDF source compiled successfully, but can't intialize? Is it possible there are some mistakes in the UDF code?

Thanks any help.

Erica

Hi,

There are many work arounds to avoid that error. Fluent doesn't keep the data that it doesn't need. If you need the data..e.g. previous temperature at the wall or something...then one way to get it it by using a User Defined Memory. There is a way of telling the Fluent "black box" code to creat a memory location and save whatever data you need later for your UDF.

I don't know your particular case but in general Fluent doesn't have anything at the begining of the transient iteration except for the inital data...so you have to insert a little "if command.." like

if CURRENT_TIME = 0.0 or some time you have.. then return else .. run the UDF..

this lets u skip the initial time step. This is what I can say so far...but there might be someother work around. Keep on tying. its experiment afterall only on PC tho.

Melaku H.

rgds