anatman
Mechanical
- Jan 30, 2012
- 9
thread384-152064
Sorry to start a new thread on this but the other one that referenced this topic was closed. In the previous discussion (see above reference post) entitled "Bell modes? for a circular tube" there was mention of a ring frequency formula posted by electricpete where he compared it to the "breathing mode" and offered the following equation:
Ring frequency = sqrt(E/mu) / (Pi*d)
My first question; is there another formula for determining the RBM of a hollow cylinder or is this indeed the same vibrational mode as the ring frequency referenced in the original discussion. His description of the ring freq leads me to believe that they are one in the same, however can someone please confirm this for me?
Regarding the equation; the mu was initially noted as referring to the mass density, however further down in the discussion the mu appears to be replaced with rho as follows:
"So now you can see why the formula for the ring frequency involves the longitudinal wave speed (sqrt(E/rho)). It is becasue the motion is caused by longitudinal strain in the cylinder material."
Given the latter statement, this would indicate to me that it's actually referring to mass per unit length. Can someone please verify for me whether or not this is correct? And if so then can someone please confirm that the mass per unit length is the Area * mass per unit volume (i.e., PI*d*t*density)?
Thanks!
Sorry to start a new thread on this but the other one that referenced this topic was closed. In the previous discussion (see above reference post) entitled "Bell modes? for a circular tube" there was mention of a ring frequency formula posted by electricpete where he compared it to the "breathing mode" and offered the following equation:
Ring frequency = sqrt(E/mu) / (Pi*d)
My first question; is there another formula for determining the RBM of a hollow cylinder or is this indeed the same vibrational mode as the ring frequency referenced in the original discussion. His description of the ring freq leads me to believe that they are one in the same, however can someone please confirm this for me?
Regarding the equation; the mu was initially noted as referring to the mass density, however further down in the discussion the mu appears to be replaced with rho as follows:
"So now you can see why the formula for the ring frequency involves the longitudinal wave speed (sqrt(E/rho)). It is becasue the motion is caused by longitudinal strain in the cylinder material."
Given the latter statement, this would indicate to me that it's actually referring to mass per unit length. Can someone please verify for me whether or not this is correct? And if so then can someone please confirm that the mass per unit length is the Area * mass per unit volume (i.e., PI*d*t*density)?
Thanks!
