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salman December 21, 2006 15:09

problem defining inlet velocity direction
 
hello, my problem deals with a 3D geometry with inlet at the top and the outlet in the side,that isin the horizontal direction.as here the velocity and the gravity is in the negative z-direction.i defined the inlet velocity and the gravity in the negative z-direction.but when i check the mass fluxes there it shows negative value of inlet mass flow rate and positive value of outlet mass flow rate.but actually inlet mass flow rate will be positive and the outlet mass flow rate will be negative.

please help me out .

thanks.


Ryan December 21, 2006 20:37

Re: problem defining inlet velocity direction
 
Hi salman,

Masflow entering the domain is Negative and leaving is positive.

you are getting the right results is presume.

Anything given away from a domain in +ve and taken in is -ve.

Regards

Rajit

salman December 21, 2006 23:16

Re: problem defining inlet velocity direction
 
thanks ranjit for a quick reply. i need one more help. in my problem,i need to create a fully developed flow at the inlet. can you help me in getting the udf in 3D with inlet axis in the negative z-direction, thanks


Nak January 3, 2007 12:34

Re: problem defining inlet velocity direction
 
Extend the inlet geometry by 5 times the diameter to get the fully developed profile. It may take longer time for computation, but it should work if you don't get the UDF to copy from anywhere. By the way Salman miyaan, I thought you had finished working on this !

Good luck.


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