3-D Finite Element Analysis Of Polypropylene Tubular Loop Reactor

In this thesis, finite element analysis is carried out on a large polypropylene tubular loop reactor which is complicated both in structure and loadings. By using shell elements for meshing, modeling of the reactor is simplified, its node number is reduced, and calculation speed increased. The natural frequencies and the corresponding vibration modals of the reactor are obtained by performing modal analysis so that the dynamic responses of the reactor to the wind and earthquake loadings can be determined. After analyzing all the possible loadings and working states of the reactor, six most serious combined load cases are chosen to be used to calculate stress intensities in the reactor by application of superpositionprinciples. Based on the JB4732-1995 《Steel Pressure Vessels-Designby Analysis》 and some reasonable suppositions, strength check is carried out on the reactor and the main strength sizes are determined which form the bases for the design of the reactor. Spectrum analysis is also performed on the rector to obtain its response to earthquake loading and the results are compared with those obtained from the method of equivalent earthquake loading which is generally used in the design of pressure vessels.This study shows that finite element analysis is an effective method for determining the strength sizes of the tubular loop reactor and is able to optimize the structure for the reactor, thus, the difficulties for design of thereactor are solved.