An Optimal Location of Elliptical Cross Bore in Elastic Pressurized Thick Cylinders

Abstract

Finite Element Analysis (FEA) was performed on elastic pressurized thick walled cylinder to determine the optimal location for an elliptical shaped cross bore. Preliminary investigations were performed on a radial elliptical shaped cross bore to establish an optimum diameter ratio in a cylinder with thickness ratio of 2.0.The cross bore diameter with size ratio of 2.0 gave the lowest Stress Concentration Factor (SCF) at 1.89.Henceforth,only the optimal diameter size ratio was used for further optimal analyses. The optimization process was then done on cross bored cylinders of thickness ratios of 1.4 up to 3.0 at various offset locations along the radial X axis of the cylinder. The study covered offset locations between the radial position of the cylinder and the offset ratio of 0.9. The authors established that offsetting of an elliptically shaped cross bores increases the magnitude of SCFs. Overall, lowest SCF occurred at radial position when K=2.5 with a magnitude of 1.733. This lowest SCF magnitude indicated a reduction of pressure carrying capacity of 42.3% in comparison to a similar plain cylinder without a cross bore.