Pressure vessel modeling and simulation method based on thickness prediction and coordinate mapping

Considering the characteristics of variable thickness and winding angles of pressure vessel dome, this paper compared different thickness prediction methods, including the single formula and Knoell equation method. Based on cubic spline curves that ensure the continuity of the first derivative, the profile of each winding layer at the dome were predicted. Combining the calculation method of winding angles, the three-dimensional coordinate vector of any point on the vessel in the Cartesian coordinate system was derived, achieving the coordinate mapping. Based on the progressive damage analysis, the simulation prediction of the burst strength of the pressure vessel was conducted. The accuracy of the modeling method was ultimately verified through hydrostatic burst tests. Furthermore, the effects of layer methods on the burst pressure of the vessel were investigated. The results indicate that the spline curve has the highest accuracy in predicting head thickness. The established coordinate mapping method can accurately represent the winding angles of the pressure vessel. The predicted hydrostatic burst strength is 38.25 MPa, and the average test result is 40.4 MPa, with a relative error of approximately −5.3%, verifying the correctness of the modeling method in this paper. The ply sequence has no significant effect on burst strength, and when the longitudinal/circumferential winding thickness ratio is about 1.2, the hydrostatic burst strength is the highest.