bundary condition

hamid1 · November 22, 2011, 12:39

Dear All
Is imposing velocity with minus value at boundary condition correct?

Regards

papteo · November 22, 2011, 12:51

it depends on the way you define the velocity! if it is set to normal to boundary then with minus the fluid would never enter the domain! but if you define it through the 3 coordinates it is correct as long as the inlet has the opposite orientation from the axes!

hamid1 · November 23, 2011, 04:08

its a suction boundary condition and i know the velocity of exiting fluid.. so can i impose this velocity (which is minus) to bc?
another question is if fluent has any coordinate system? meaning that while imposing any b.c. one should have pay attention to the orientation of the flow?

papteo · November 23, 2011, 04:47

i refuse to answer to your question, look first at the User Guide for such easy querries!

November 22, 2011, 12:39	bundary condition	#1
hamid1 Senior Member hamid Join Date: Nov 2010 Posts: 185 Rep Power: 16	Dear All Is imposing velocity with minus value at boundary condition correct? Regards

November 22, 2011, 12:51		#2
papteo Member Theodoros Papadopoulos Join Date: Mar 2011 Posts: 36 Rep Power: 15	it depends on the way you define the velocity! if it is set to normal to boundary then with minus the fluid would never enter the domain! but if you define it through the 3 coordinates it is correct as long as the inlet has the opposite orientation from the axes! laurentb and BMCombustor like this.

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November 23, 2011, 04:08		#3
hamid1 Senior Member hamid Join Date: Nov 2010 Posts: 185 Rep Power: 16	its a suction boundary condition and i know the velocity of exiting fluid.. so can i impose this velocity (which is minus) to bc? another question is if fluent has any coordinate system? meaning that while imposing any b.c. one should have pay attention to the orientation of the flow?

November 23, 2011, 04:47		#4
papteo Member Theodoros Papadopoulos Join Date: Mar 2011 Posts: 36 Rep Power: 15	i refuse to answer to your question, look first at the User Guide for such easy querries!