problem regarding unsteady laminar flow

adityanadig · January 20, 2017, 03:31

Hello All,

I am working on a unsteady laminar flow problem with pulsating input of velocity. The parameter i am interested in is wall shear stress and its average value.

The average value of wall shear stress and oscillatory shear index is defined by formulas in attachment.

I have Average value of wall shear stress and i want to know,how i can calculate the oscillatory shear index. I need to plot OSI in scalar plot.

FMDenaro · January 20, 2017, 04:00

what is your problem? you can just compute the time integrals as the simulation progress, then, at the end of the period T, you divide by T and get the ratio.

adityanadig · January 20, 2017, 04:21

But in the OSI formula the numerator is Modulus of the average wall shear stress. My time limits lie between 1sec and 2sec.

how to implement this in simulation? and get the scalar plots.

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January 20, 2017, 04:00		#2
FMDenaro Senior Member Filippo Maria Denaro Join Date: Jul 2010 Posts: 6,768 Rep Power: 71	what is your problem? you can just compute the time integrals as the simulation progress, then, at the end of the period T, you divide by T and get the ratio.

January 20, 2017, 04:21		#3
adityanadig New Member Join Date: Jan 2017 Posts: 5 Rep Power: 9	But in the OSI formula the numerator is Modulus of the average wall shear stress. My time limits lie between 1sec and 2sec. how to implement this in simulation? and get the scalar plots.