Accession Number:

ADA310648

Title:

A Closed-Form Dynamic Elasticity Solution to the Fluid/Structure Interaction Problem of a Two-Layer Infinite Viscoelastic Cylinder with Inner and Outer Fluid Loading Subject to Forced Harmonic Excitation.

Descriptive Note:

Final rept.,

Corporate Author:

NAVAL UNDERSEA WARFARE CENTER NEWPORT DIV RI

Personal Author(s):

Report Date:

1995-12-29

Pagination or Media Count:

264.0

Abstract:

This report documents an exact closed-form solution to the problem of a two-layer viscoelastic solid infinite cylinder that is immersed in an infinite ideal inviscid fluid and contains an infinite ideal inviscid fluid within its diameter. The viscoelasticity is modeled with structural damping, which is incorporated by the use of a complex modulus of elasticity. The composite system is subject to forced harmonic vibration at the outer solidfluid interface. The response to both nonaxisymmetric described in terms of circumferential order number n and axisymmetric excitations is derived. The problem is resolved with a three-dimensional dynamic elasticity solution. Simulations of the transfer surfaces for the interior pressure field are performed for radial excitation P0 and longitudinal excitation Px applied to a single-layer cylinder for n 0, 1, and 2. The circumferential excitation P theta is applied to the single-layer cylinder for interior pressure simulation with n 1 and 2. Simulations of the circumferential strain are performed for excitations P0 and Px applied to a two-layer cylinder for n 0. Additionally, the P0 excitation is applied to the two-layer cylinder for n 0, 1, and 2, resulting in simulations for the pressure field in the inner fluid. Simulations are displayed as response transfer surfaces in the longitudinal wavenumber-frequency plane. Comparisons are made between the elasticity models derived in this report and the membrane and bending shell models from previous work. The nulls occurring in the interior pressure field at higher frequencies are explored as well as the resonances relating to the thickness of the cylinder.

Subject Categories:

  • Fluid Mechanics
  • Mechanics

Distribution Statement:

APPROVED FOR PUBLIC RELEASE