APPLICATION OF THE FINITE ELEMENT METHOD IN INVESTIGATION OF DYNAMICS OF STRUCTURAL PARTS OF AN ELECTRIC MACHINE
Author: RNDr. B. Madejewski, CSc., Research Institute of Electric Machines, Brno
The author describes in an instructive way a possibility of application of the finite element method in the design of the fan cover.
Reviewed by: Doc. Ing. Věra Chalupová, CSc.
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1. INTRODUCTION
A part of mechanics dealing with the study of motion of physical systems caused by external forces is called dynamics. Vibratory motion is one of the types of the dynamic behaviour of the system.
Vibratory motions can be divided into two basic groups according to the character of their behaviour – linear and non-linear systems. The principle of superposition, simplifying significantly the procedure of the solution, applies for the first of them. Description and solution of non-linear problems is considerably more complicated and we will not dwell on them in our considerations. Vibratory motion can be further divided into two basic categories – inherent and forced motion. In a general case also the appropriate attenuation of the system must be taken into account. The paper will be dealing in detail with the solution of linear, forced and attenuated vibratory motion of the physical system being investigated.
(taken from Center of environmental hygiene of State Health Institute Prague)
Noise is every unwanted sound that is disturbing or troublesome or that affects adversely human health. Negative effects of noise on human health are partly specific ones, presented by disorders of the function of acoustic analyzer, partly non-specific ones (extra hearing), when functions of various systems of the organism are affected. These non-specific system effects appear almost in the whole range of noise intensities, frequently they are accompanied by stress reaction and impact on neurohumoral a neurovegetative regulation, biochemical reactions, sleep, higher nervous functions, such as learning and memory, impact on sensory motoric functions and coordination.
…(more…)Authors:
RNDr. B. Madejewski,CSc., Ing. V. Kotrba, CSc.
The article describes the design, calculation and test results noise attenuation of the noise hood for large industrial compressors driven by electric motors. Predicted noise attenuation (software UTLUM) has been validated by practical measurements at the customer¢s place.
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