Learning Forum

[hhusker]

I haven't had the chance to work with fluent before, hence I was wondering. I need to simulate an impedance tube test to find transmission loss of a prestressed structure. The structure in prestressed by inflating it. What would be the optimal way for me to simulate the deformation the structure undergoes while air is pumped into it in varying pressure loads? Is static acoustics enough or should I explore using fluent to simulate this deformation inside the structure due to inflation? I need to couple this with harmonic acoustics to extract the transmission loss of the pre stressed.nPlease do correct me If I am going about this incorrectly. n

[peteroznewman]

nStatic Structural can take a structure, such as a tube, and apply a pressure load to the inside face to generate a pre-stress for a subsequent analysis. You don't need fluid to apply pressure to the inside of the tube. Pressure is a load that can be applied directly to any face of a structure.nTubes are thin walled structures, so use surface geometry to represent the tube. In Mechanical, you will assign a material and wall thickness.nAcoustic models require solid elements, so you would also have a cylindrical solid the same size as the cylindrical surface used for the tube. In SpaceClaim, on the Workbench tab, you click the Share button. That tells the mesher in mechanical to put one set of nodes on the cylindrical surface and create structural shell elements on the surface while filling the volume with solid elements that will compute the acoustic pressure.n

[hhusker]

Hi Peter,nYou had helped me with the same impedance tube and pre stressing long while ago. This time, my question is regarding how to simulate inflation. I would like to see how the prototype structure would deform when I subject it to air pressure. I want the structure inside to expand and then run the acoustic tests. The structure is provided with hole for air supply. I am not looking to pre stress the impedance tube itself. I was hoping to simulate air flowing through the holes. Are you suggesting using static acoustics and apply pressure on the walls inside? or can I apply to the air cavity defined directly?nI apologize if I am not being articulate enough.nn

[peteroznewman]

nIf you apply a pressure load to the faces of a structure, Static Structural will simulate the effect of inflation without moving any air. Maybe you can hide the faces of the impedance tube and show the structure you want to inflate. How much will the structure expand?n