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 Sushmita May 14, 2005 07:01

Boundary condition for linear temperature

dear all, i need ur help. i am a new user of starcd. i want to know how to apply boundary condition for linear temperature distribution along a wall. and is it possible to apply such boundary coditions using table manipulation? pls help if u know the matter. thank u all. take care bye Sushmita

 sankar May 16, 2005 01:04

Re: Boundary condition for linear temperature

yes u can apply the linear temp dist. using a table in that independant variable is x,y or z directions.

or u can go for user coding

 Ted Crilly May 16, 2005 16:12

Re: Boundary condition for linear temperature

just interested?

where would you need to apply a linear temperature distribution?

what are you trying to model exactly?

cheers

-ted

 Sushmita May 16, 2005 23:12

Re: Boundary condition for linear temperature

dear ted, suppose there is a cubical cavity with air in it. and the heating is from bottom to upper surface. and the temperature in the side walls is linearly increasing. in that case how to apply that boundary condition in the side wall. if possible then pls help. i need ur help. bye sushmita.

 sankar May 17, 2005 00:46

Re: Boundary condition for linear temperature

The actual boundary condition will be heatflux applied at the bottom of the wall.temperature distribution will be calculated bythe program.

 sushmita May 23, 2005 07:13

Re: Boundary condition for linear temperature

dear Shankar and ted, i am looking for ur help in this regard. pls help me. bye take care. sushmita

 sankar May 23, 2005 09:56

Re: Boundary condition for linear temperature

yes, If u state clearly on what u want to do, we can help you.

rgds

sankar

 sushmita May 24, 2005 03:58

Re: Boundary condition for linear temperature

Shankar, thanks for ur reply. i am explaining u the problem briefly: suppose u have a cubical room. that means it has six walls. the bottom wall is hot and the top wall has a temperature 8 degree less than the bottom wall. other side walls (4 in number) has linearly increasing temperature from bottom to top. i want to know from u that how i have to apply the boundary condition at the side walls for linearly varying temperature.

pls help me. it is very urgent for me. thanks once again. bye take care Sushmita.

 sankar May 24, 2005 05:08

Re: Boundary condition for linear temperature

Hi,

here u know the temperature difference between two walls(top and bottom). But you should know the thermal conditions of the side walls it can be

1- insulated 2-f some thermal resistance( heat transfer) 3-heat coming in or out

thermal condiotn are as follows

1- give adiabatic wall boundary conditions 2- fixed wall with some temp and thermal resistance 3- apply heat flux

If you want to specify boundary values that changes spacially you have to use table. dont use standard bopundary condition

 sushmita May 25, 2005 22:40

Re: Boundary condition for linear temperature

BYE Take care. Sushmita

 sushmita May 25, 2005 22:48

Re: Boundary condition for linear temperature

Sankar, another thing. can u pls tell me if i want to use fortran programm instead of table then what should i do and how. pls help. thank u. BYE Take care. Sushmita

 sankar May 28, 2005 02:20

Re: Boundary condition for linear temperature

hi,

if you want to use usercoding 1.u should have Absoft fortran 2.go 2 define boundary regions>wall 3.instead of standard define user 4.dont define any value click apply 5.This will generate a file called bcdefiw.f 6.All parameters will be there in that file 7.define like this TORHF = a+b*X

where TORHF is temperature dependant variable X,Y,Z are distance independant variable

this is the procedure

rgds

sankar

 sushmita May 28, 2005 06:39

Re: Boundary condition for linear temperature

Sankar, thanks a lot for ur help. i am grateful to u BYE take care Sushmita

 balasubramani June 21, 2005 06:27