ANSYS varification manual 9

# A restart is included to demonstrate and test this

This preview shows page 1. Sign up to view the full content.

This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: E = 30 x 106 psi υ = 0.3 ρ = 7.4167 x 10-4 lb-sec2/in4 For water: C = 57480 in/sec (speed of sound in water) ρ = 9.6333 x 10-5 lb-sec2/in4 Geometric Properties a = 10 in b = 30 in t = .25 in Analysis Assumptions and Modeling Notes For this problem, the fluid is assumed as extending only to a finite radius b where the pressure Po is zero and b is taken to be 30 inches. From the reference, this assumption should result in an error of less than 1% compared to the frequency for an unbounded fluid (b = ∞ ). The natural boundary conditions at the coordinate axes imply that δP / δx = 0 at x = 0 and δP / δy = 0 at y = 0. This problem is solved using two separate analyses. The first, using 3-D acoustic fluid elements (FLUID30) with quadrilateral shell elements (SHELL63), and the second, using 2-D acoustic fluid elements (FLUID29) with 2-D elastic beam elements (BEAM3). In the first case, due to fluid-structure coupling involving unsymmetric matrices, the natural frequency is determined by performing a full harmonic (ANTYPE = 3) analysi...
View Full Document

## This note was uploaded on 12/09/2010 for the course DEPARTMENT E301 taught by Professor Kulasinghe during the Spring '09 term at University of Peradeniya.

Ask a homework question - tutors are online