Notice of Retraction: Shock response analysis for a propulsion shaft unit by a modified TMT

The shock spectrum of gearbox was gotten according to German specification. And the equivalent time-domain acceleration curve was converted from shock spectrum. After the dynamic finite element model of entire gearbox was established by using the truss element, spring element and tetrahedral element, the shock response including the vibration velocity, acceleration and dynamic stress of gearbox subjected to the acceleration shock excitation were simulated. At last, the anti-shock performance of gearbox was analyzed combining with the strength criterion.

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Shock Response Analysis for a Propulsion Shaft System in Time Domain

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.58-60.2534 ◽

2011 ◽

Vol 58-60 ◽

pp. 2534-2539 ◽

Cited By ~ 1

Author(s):

Yan Qing Wang ◽

Rong Yu ◽

Rong Ling Chen

Keyword(s):

Initial Stress ◽

Time Domain ◽

Thrust Bearing ◽

Maximum Amplitude ◽

Response Analysis ◽

Total Response ◽

Gyroscopic Effect ◽

Obvious Effect ◽

Shaft System ◽

Shock Response

By a transfer matrix-Newmark formulation iteration method, shock response analysis in time domain was performed for a propulsion shaft subjected to base-transferred shock excitations. In order to eliminate the numerical instability of TMT, the transfer vector is used, instead of the traditional one. Influences of gyroscopic effect and initial stress on response were investigated. Main conclusions are that gyroscopic effect has no obvious effect on shock response. Initial stress increases the total shock response, but the total response isn’t equal to the absolute sum of initial stress and shock excitations acting alone. Both ends of the shaft, that are propeller and thrust bearing locations, are weaker to bear shock excitations. Maximum amplitude of response occurs at the propeller location.

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Guidelines for the Use of Approximations in Shock Response Analysis of Electronic Assemblies

Journal of Electronic Packaging ◽

10.1115/1.2909292 ◽

1993 ◽

Vol 115 (1) ◽

pp. 124-130 ◽

Cited By ~ 7

Author(s):

R. F. Keltie ◽

K. J. Falter

Keyword(s):

Finite Element Analysis ◽

Rigid Body ◽

Simple Structure ◽

Response Analysis ◽

Element Analysis ◽

Simply Supported ◽

Inappropriate Use ◽

The Finite Element Analysis ◽

Shock Response ◽

Electronic Assemblies

In order to reduce the time and effort to create models and prevent excessive computer run times, approximations and simplifications are often used in the finite element analysis of the shock response of electronic assemblies. Typical approximations which might be used include neglecting components which have small masses and considering highly stiff connections as rigid connections. It is difficult to determine under what conditions approximations may be applied and to what extent they affect a model’s accuracy. Rather than depending only on an analyst’s experience or intuition, guidelines are desirable to prevent the inappropriate use of approximations. To illustrate the methodology for developing guidelines, this paper examines approximations involving a simple structure which is representative of structures found in electronic assemblies. This structure consists of a rigid body attached by a flexible connection to a beam. Approximations considered were: approximating the stiffness of the connection, neglecting the mass of the rigid body, and approximating the boundary conditions of the beam as either simply-supported or clamped. In developing guidelines a large number of individual analyses were necessary. An important aspect of this investigation is our proposal for a concise format for presenting the results of many analyses. The techniques which were used to reduce the amount of data to be presented are discussed.

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