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Pressure gradient vs time plot

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Hi,
I have solved a pulsating fluid flow problem in a straight cylindrical duct.Now I would like to obtain a plot for 'pressure difference between inlet and exit of duct 'vs 'time'(to see the variation of pressure gradient with time).Can anyone suggest me about doing that..Thanks in advance

SM Ananth

1 Reply Last Post 25.02.2011, 11:21 GMT-5
Ivar KJELBERG COMSOL Multiphysics(r) fan, retired, former "Senior Expert" at CSEM SA (CH)

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Posted: 1 decade ago 25.02.2011, 11:21 GMT-5
Hi

you want the average velocity ? then integrate or average the inlet and the outlet (i.e.over u if the flow is along "x") and call them as variables

Vin_ave = aveop1(u)
Vout_ave = aveop2(u)

and then do a Derived Values Global Evaluation of "Vout_ave - Vin_ave"

That was for v4.
In V3.5 you do not have the average operator but you can use two integration coupling boundary variable of "int_u = int_of u" and another of "int_1 = int_of 1", and then define a user variable Vin_ave = int_u / int_1
An plot the post processing value difference of the two
--
Good luck
Ivar
Hi you want the average velocity ? then integrate or average the inlet and the outlet (i.e.over u if the flow is along "x") and call them as variables Vin_ave = aveop1(u) Vout_ave = aveop2(u) and then do a Derived Values Global Evaluation of "Vout_ave - Vin_ave" That was for v4. In V3.5 you do not have the average operator but you can use two integration coupling boundary variable of "int_u = int_of u" and another of "int_1 = int_of 1", and then define a user variable Vin_ave = int_u / int_1 An plot the post processing value difference of the two -- Good luck Ivar

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