Different material in different domain
 

Hi,

how to give different material in different domains, if i change the material in one domain then it becomes material in all the domains

Re: Different material in different domain
 

Dear sir,

I am at present using ansys 11 my problem is to analysis the rate of heat transfer from on fluid to another fluid through parallel-pipe heat exchanger.

1. When i am modelling a parallel pipe and use fill command to add fluid domain the outer pipe by default take whole reagion inside it. This means it take inside pipe as fluid domain.

kindly help me out

Re: Different material in different domain
 

Hi,

there is a CEL function called "inside()@locator", it helps to create domain-dependent expressions. You will find more information in the CFX users guide.

Variable Density:

density=(1[kg*m^-3])*inside()@Domain1+(1.5[kg*m^-3])*inside()@Domain2

Hope it helps,

Greg

Re: Different material in different domain
 

Hi,

Greg's suggestion is one way of doing it, it can also be done by defining one fluid to one domain and another fluid to another domain. I have never done it but I know it can be done.

Glenn Horrocks

Re: Different material in different domain
 

Hi,

I think it can be only done by Gregs way, i have tried in cfx 10&11 giving different fluid in different domain , it dosent work, but if u have one domain solid then its possible. thanks a lot

Re: Different material in different domain
 

Dear Cheeku,

Greg's approach is an old trick used in other CFD codes. It works only when all the additional models are the same on both side of the solid. For example, k-epsilon in the inside and outside the pipe. If you want laminar on one side, and turbulent flow on the other side, Greg's approach breaks.

If you are using CFX-11.0, right click on Simulation, and turn off "Constant Domain Physics".. The behavior you have observed is to maintain all the fluid domains the same, turning it off will allow to setup your heat exchanger model. However, NOTE that CFX-Pre will stop making some consistency checks and it is up to you to guarantee a valid physics setup.

ANSYS CFX is a full multidomain physics package, no need for workaround like Greg explained. What you are trying to do, it has been done by several users since the release of CFX-5.7.1.

Hope this helps,

Opaque

Re: Different material in different domain
 

Hi cheeku As per my understanding your problem is that although you change the material for different it takes same in all domain. For this you do one thing.
:Right click on my computer
: in advance click on enviorment
: in variable create variable
:in new variable name and valu you feed CFX5_no_CONSTANT_PHYSICS for value -t ok by.........