Radial displacement of rotating cylinder
Radial displacement of rotating cylinder
(OP)
Hello,
I am performing a static study in SW '10 to determine the max. radial displacement of a rotating piston rigidly attached to a shaft rotating at 3600 RPM. I actually have the piston and shaft drawn as one part and have two bearing journal surfaces on the shaft where I am applying fixtures that only the shaft to rotate around its axis. I applied a angular velocity of 60 hz. I am not confident in the results I am seeing for displacement on the circumfrance of the piston, possibly due to incorrect setup. Attached is a .jpg of the shaft. It is a 3" shaft with an 11" piston and it's saying the max deflection on the perimeter is around .25".
I am performing a static study in SW '10 to determine the max. radial displacement of a rotating piston rigidly attached to a shaft rotating at 3600 RPM. I actually have the piston and shaft drawn as one part and have two bearing journal surfaces on the shaft where I am applying fixtures that only the shaft to rotate around its axis. I applied a angular velocity of 60 hz. I am not confident in the results I am seeing for displacement on the circumfrance of the piston, possibly due to incorrect setup. Attached is a .jpg of the shaft. It is a 3" shaft with an 11" piston and it's saying the max deflection on the perimeter is around .25".






RE: Radial displacement of rotating cylinder
TOP
CSWP, BSSE
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RE: Radial displacement of rotating cylinder
RE: Radial displacement of rotating cylinder
You realize that the math model, the nodes and elements don't actually rotate. A radial acceleration is applied. Since you are plotting URes you are not seeing radial displacement at all. You are seeing circumferential displacement. Turn on a vector plot when you do your displacement plot. I'll betcha that the arrows are tangential. That is how you can have such a huge displacement under a radial constraint where displacement is supposed to be zero.
To put it another way, your model is underconstrained and is flying off into space in a rotational kind of way.
TOP
CSWP, BSSE
www.engtran.com www.niswug.org
www.linkedin.com/in/engineeringtransport
"Node news is good news."
RE: Radial displacement of rotating cylinder
thanks.
RE: Radial displacement of rotating cylinder
Building Better Products with Finite Element Analysis, Vince Adams and Abraham Askenazi, Onward Press, 1999 (out of print)
Concepts and Applications of Finite Element Analysis, Robert Cook, John Wiley and Sons, 1989
Finite Element Procedures in Engineering Analysis, Klaus-Jurgen Bathe, Prentice Hall, 1982
Finite Element Handbook, Hayrettin Kardestuncer, McGraw Hill, 1987
TOP
CSWP, BSSE
www.engtran.com www.niswug.org
www.linkedin.com/in/engineeringtransport
"Node news is good news."