Optimization of Nozzle Hole Reinforcement Parameters and Wall Thickness in Cylindrical Pressure Vessel Using FEM
Keywords:
Pressure vessels, Stress Concentration Factor (SCF), Finite Element Method (FEM), elliptical holeAbstract
Nozzle openings in pressure vessels are indispensable, and all the pressure vessels must have nozzle openings to facilitate transfer of fluid from and to the vessel. These holes are responsible for geometric discontinuities. Stresses around the vicinity of the nozzle openings are comparatively higher and this leads to the failure of the vessel. Additional materials should be provided near the openings to strengthen the vessel and also to reduce the stress concentration factor. Three dimensional finite element models were developed for three different internal diameters namely 200, 250, 300mm with circular and elliptical openings and analyzed with appropriate boundary conditions using finite element method (FEM). Results indicate that introducing elliptical hole with appropriate major and minor axis orientation rather than circular hole significantly reduces the stress concentration factor. As a further step, reinforcement parameters and nozzle wall thickness were optimized.
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References
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