Accession Number : ADA321556

Title :   Box-Like Seating Structures; Interface Shape Dependence.

Descriptive Note : Partial rept.,

Corporate Author : TECHNISCH PHYSISCHE DIENST TNO-TH DELFT (NETHERLANDS)

Personal Author(s) : Petersson, Bjoern A.

PDF Url : ADA321556

Report Date : OCT 1996

Pagination or Media Count : 30

Abstract : The influence of the shape of the interface between a superstructure and a recipient on the vibrational energy transmission is analyzed. The real parts of the zero and first order interface mobilities are derived for a basic rectangular shape. Numerical results are presented for various aspect ratios but comparisons are also made with the corresponding results for an annular shape. It is concluded that the primary parameter is the perimeter of the interface and the condition that the wavelength is larger than the perimeter constitutes the transition from point to distributed contact. Also it is demonstrated that for closed-contour, strip-like interfaces, the real parts are independent of the strip width in a large and practically relevant range. With respect to the zero order interface mobility, the aspect ratio is of subordinate importance for the overall trend whereas the details of the signature are influenced. In contrast, the first order interface mobility includes two orthogonal cases, which are affected differently by the aspect ratio. Straightforward estimation procedures are developed for both interface mobilities.

Descriptors :   *VIBRATION, *INTERFACES, *GEOMETRIC FORMS, *SHIP STRUCTURAL COMPONENTS, *SUPERSTRUCTURES, MOBILITY, NETHERLANDS, PARAMETERS, EXCITATION, INTEGRALS, ENERGY, NUMERICAL ANALYSIS, ELECTROMAGNETIC WAVE PROPAGATION, TRANSMITTANCE, WAVE PROPAGATION, RECTANGULAR BODIES, PARTIAL DIFFERENTIAL EQUATIONS, ACOUSTIC SIGNALS, DUTCH LANGUAGE, ORTHOGONALITY, ASPECT RATIO, BESSEL FUNCTIONS, BOX BEAMS, HELMHOLTZ EQUATIONS.

Subject Categories : Theoretical Mathematics
      Computer Programming and Software
      Mechanics
      Electromagnetic Pulses

Distribution Statement : APPROVED FOR PUBLIC RELEASE