CFD Online Discussion Forums

CFD Online Discussion Forums (http://www.cfd-online.com/Forums/)
-   Main CFD Forum (http://www.cfd-online.com/Forums/main/)
-   -   flow in cylinder (http://www.cfd-online.com/Forums/main/107013-flow-cylinder.html)

nhosseini September 15, 2012 03:48

flow in cylinder
 
Hi every body!

I would be so thankful if any body could help me about the physical solution of

in-compressible flow in cylinder.

a flow is at rest in the initial and suddenly a piston at left end of cylinder starts

to move with constant speed of Vpiston, what would be velocity and pressure values in cylinder?

Jonas Holdeman September 15, 2012 09:25

I would expect that the entire column of fluid would instantly start moving with the piston at a velocity Vpiston (because of incompressibility) and a slug profile. Over time a fully-developed profile would develop ahead of the piston. Look at the problem in the frame of the piston. Then the cylinder would start moving toward the piston with a velocity -Vpiston.

nhosseini September 15, 2012 11:43

it seems that your comment is correct, but when I want to solve it numerically with control volume scheme it takes time to reach the constant velocity, and it doesn't instantly moves to answer, I would be thankful if you could help me


All times are GMT -4. The time now is 09:58.