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Evan January 21, 2009 16:00

Mass Increase for closed system with moving wall
My issue is with a closed system filled with an ideal gas. It is a 2D axisymmetric model which also includes a moving wall representing a pressure wave generator or piston-cylinder assembly. The problem is the system's mass is steadily increasing. I have tried several variations on modeling the moving wall using various smoothing techniques. I am certain the moving mesh and its UDF is working properly with visual reference, however I believe the code is somehow adding mass on the back stroke.

Any help would be greatly appreciated. Thanks.

simonart7 June 8, 2012 03:20

Coupled Flow _ Rigid Body Motion - Battery Cooling
I have the same problem.
My mass flow rate is alternating increasing up to 700%.
The Residuals seems to be ok, but Tke and Tdr pass up quick above 1.

sanjeetlimbu April 21, 2015 15:14

4 Attachment(s)
I am getting no pressure and temperature rise for rapid compression in fluid 2D axi-symetric acse

I have entered these values at initialisation

Problem is that I am not geting temp and pressure rise during compression stroke

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