Optimal design of thin walled I beams for extreme natural frequency of torsional vibrations

This paper treats the optimal design of a vertical column that is built-in at the lower end. In addition to its own weight, the column is to carry an axial compressive load at its unsupported upper end. The column is to be designed as a thin-walled tube. The median line is to be the same for all cross sections; the wall thickness, though constant along the median line of any cross section, is allowed to vary along the length of the tube. Accordingly, the weight per unit length of the tube is proportional to the bending stiffness. For given length and total weight, the variation of the wall thickness along the column is to be determined to maximize the critical value of the compressive load at the upper end. The influence of a maximum allowable compressive stress on the design is also investigated.

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Paper 6: Torsional Vibrations in Fuel Injection Pump Drive Systems with Special Reference to Automotive Engines

Proceedings of the Institution of Mechanical Engineers Conference Proceedings ◽

10.1243/pime_conf_1966_181_150_02 ◽

1966 ◽

Vol 181 (8) ◽

pp. 84-90

Author(s):

L. F. Martyn ◽

T. M. B. Silcock

Keyword(s):

Diesel Engine ◽

Natural Frequency ◽

Fuel Injection ◽

Torsional Vibrations ◽

Pump System ◽

Automotive Engines ◽

Injection Pump ◽

Infinite Mass ◽

Fuel Injection Pump ◽

Drive Systems

The torsional vibrations which occur on the fuel injection pump of an automotive diesel engine were investigated. Calculations and tests showed that as well as vibrations transmitted from the crankshaft, the fuel pump could vibrate at the natural frequency of the torsional system consisting of the pump and the drive coupling against an infinite mass. This was excited by harmonic torques produced by the pump. Calculations were made to show the effect of variables on the natural frequency of the pump system including the instance when a crankshaft natural frequency coincided with a pump natural frequency. Calculations were also made of the effect of the engine harmonic torques on the pump vibrations. The results were verified by experiments.

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Optimal design of thin-walled functionally graded beams for buckling problems

Composite Structures ◽

10.1016/j.compstruct.2017.07.024 ◽

2017 ◽

Vol 179 ◽

pp. 459-467 ◽

Cited By ~ 7

Author(s):

Tan-Tien Nguyen ◽

Jaehong Lee

Keyword(s):

Optimal Design ◽

Functionally Graded ◽

Thin Walled

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Derivatives of Eigenvalues for Torsional Vibration of Geared Shaft Systems

Journal of Vibration and Acoustics ◽

10.1115/1.2930345 ◽

1993 ◽

Vol 115 (3) ◽

pp. 277-279 ◽

Cited By ~ 4

Author(s):

Liu Zhong-Sheng ◽

Chen Su-Huan ◽

Xu Tao

Keyword(s):

Sensitivity Analysis ◽

Optimal Design ◽

Natural Frequency ◽

Torsional Vibration ◽

Design Parameter ◽

Practical Importance ◽

Design Sensitivity ◽

Shaft System ◽

Eigenvalue Derivatives ◽

Derivatives Of

Design sensitivity analysis of natural frequency for geared shaft systems is of practical importance in the optimal design of these systems. This note provides a simple and easily implemented method to calculate the eigenvalue derivatives of a geared shaft system with respect to a design parameter ν, including gear inertia J, shaft stiffness K, and transmission ratio Q, when the eigensolution is known. An example is given to illustrate the method.

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