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February 17, 2012, 11:51 |
velocity cyclic BC-groovyBC
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#1 |
Senior Member
Jian Zhong
Join Date: Feb 2012
Location: Birmingham
Posts: 109
Rep Power: 14 |
Hi,
1 How to set a fixedvalue of velocity to the cyclic BC? 2 But the pressure is not cyclic, how to set a fixedgradient of pressure? --> FOAM FATAL IO ERROR: inconsistent patch and patchField types for I want to set the following fixedvalue using groovyBC. How to do that? inlet { type cyclic; type groovyBC; //type fixedValue // log-law expression uniform (0 0 0); variables "u_f=0.23;z0=0.9;z_f=pos().z-10;vel=u_f*log(z_f/z0);"; valueExpression "vector (vel,0,0)"; } outlet { type cyclic; type groovyBC; //type fixedValue // log-law expression uniform (0 0 0); variables "u_f=0.23;z0=0.9;z_f=pos().z-10;vel=u_f*log(z_f/z0);"; valueExpression "vector (vel,0,0)"; } |
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February 18, 2012, 11:12 |
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#3 |
Senior Member
Jian Zhong
Join Date: Feb 2012
Location: Birmingham
Posts: 109
Rep Power: 14 |
But I have installed the groovyBC. You mean I should write another BC? I donot know how to do that.
1 How to set a fixedvalue of velocity to the cyclic BC (inlet and outlet)? 2 But the pressure is not cyclic, how to set a fixedgradient of pressure? |
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February 18, 2012, 12:48 |
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#4 |
Senior Member
Nima Samkhaniani
Join Date: Sep 2009
Location: Tehran, Iran
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i think you should write new BC
however try this, may be it works 1) use funkySetFields and define your velocity function in whole domain at time 0 2) uses a fan boundary condition with one constant ( constant value is the fixed pressure gradient * pipe length) |
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February 19, 2012, 19:40 |
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#5 | |
Assistant Moderator
Bernhard Gschaider
Join Date: Mar 2009
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Quote:
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July 2, 2012, 12:30 |
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#6 | |
Senior Member
Jian Zhong
Join Date: Feb 2012
Location: Birmingham
Posts: 109
Rep Power: 14 |
Quote:
Could you give me some idea of how to set fixedValue and zeroGradient for cyclic inlet and outlet patches respectively? Is it possible to achieve that? Best regards, Jian |
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