how to change inlet condition in unsteady flow?

July 8, 2002, 10:36

i want to simulate a full process of unsteady flow in a pipe with one inlet before 0.2s, when t=0.2s another wall turn to be a velocity inlet and there are two velocity after 0.2s. how to define these, i guess i should use the function of "macro", but how to set the macro?

is there anyone who will give me a advice in detail ?

regards

July 8, 2002, 16:25

The is a tutorial (UDF Users' Guide) specifically detailing how you would go about specifying a transient velocity condition on a velocity-inlet boundary. Take a look see...

July 10, 2002, 01:22

I think that UDF is the only possible way.

Sincerely, Jinwook

July 12, 2002, 19:52

Hi,

I wasn't quite sure what you are trying to simulate, but I also think the use of UDF with unsteady flow settings may help. A good example can be found under Tutorial 4.

July 8, 2002, 10:36	how to change inlet condition in unsteady flow?	#1
bob Guest Posts: n/a	i want to simulate a full process of unsteady flow in a pipe with one inlet before 0.2s, when t=0.2s another wall turn to be a velocity inlet and there are two velocity after 0.2s. how to define these, i guess i should use the function of "macro", but how to set the macro? is there anyone who will give me a advice in detail ? regards

July 8, 2002, 16:25	Re: how to change inlet condition in unsteady flow	#2
Lanre Guest Posts: n/a	The is a tutorial (UDF Users' Guide) specifically detailing how you would go about specifying a transient velocity condition on a velocity-inlet boundary. Take a look see...

July 10, 2002, 01:22	Re: how to change inlet condition in unsteady flow	#3
Jin-Wook LEE Guest Posts: n/a	I think that UDF is the only possible way. Sincerely, Jinwook

July 12, 2002, 19:52	Re: how to change inlet condition in unsteady flow	#4
Duc Guest Posts: n/a	Hi, I wasn't quite sure what you are trying to simulate, but I also think the use of UDF with unsteady flow settings may help. A good example can be found under Tutorial 4.

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