Vibration Analysis of Elastic Rotational Shells Using Microcomputers
An element was developed previously which is capable of predicting the undamped natural frequencies of thin elastic shells of revolution. The above element possessed a number of features, e.g. a change in element characteristics could be achieved by a change in the input data. The above formulation has now been updated so that the internal degrees of freedom have been condensed. Also an efficient eigenvalue-economiser routine has been developed to reduce the iteration time. The routine is capable of selecting the masters analytically at a given cut off frequency. These have facilitated the storage and running of the above routines on modern micro-computers. A number of well established examples have been tackled and the results are given in the text.
KeywordsMass Matrice Cooling Tower Torsion Problem Thin Elastic Shell Shell Problem
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