How to define a dynamic Boundary Condition?

March 9, 2009, 07:29

Recently I am dealing with a 2 stages compressor. I want to vary the outlet static pressure (writeen as Ps) according to the timesteps (writeen as t). And I am going to use a function such as:

Ps=P1 t<t1 Ps=0.1*t t1<t<t2 Ps=P2 t>t2

The P1,P2,t1 and t2 are specified. So, could someone tell me that how to define the boundary condition in such a problem, should I use Fortran?

March 9, 2009, 17:55

Hi,

This can be done in CEL, no need for fortran. Have a look at the tutorial examples, some of them use CEL expressions.

Glenn Horrocks

March 10, 2009, 00:03

Thank you Glenn~ I have defined a function:Pressure(ctstep) and now it is working... Thanks again

March 9, 2009, 07:29	How to define a dynamic Boundary Condition?	#1
abrahamgx Guest Posts: n/a	Recently I am dealing with a 2 stages compressor. I want to vary the outlet static pressure (writeen as Ps) according to the timesteps (writeen as t). And I am going to use a function such as: Ps=P1 t<t1 Ps=0.1*t t1<t<t2 Ps=P2 t>t2 The P1,P2,t1 and t2 are specified. So, could someone tell me that how to define the boundary condition in such a problem, should I use Fortran?

March 9, 2009, 17:55	Re: How to define a dynamic Boundary Condition?	#2
Glenn Horrocks Guest Posts: n/a	Hi, This can be done in CEL, no need for fortran. Have a look at the tutorial examples, some of them use CEL expressions. Glenn Horrocks

March 10, 2009, 00:03	Re: How to define a dynamic Boundary Condition?	#3
abrahamgx Guest Posts: n/a	Thank you Glenn~ I have defined a function:Pressure(ctstep) and now it is working... Thanks again

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