Water-Entry Impact Performance of Torpedo′s Cushion Nose Cap

To solve the problems that theoretical analysis of water-entry impact process of torpedo′s cushion nose cap is difficult and strength design boundary of the nose cap is not easy to be determined,we build a finite element model of the nose cap water-entry with the software ABAQUS,and analyze the stress distribution of the nose cap assembly dur-ing water-entry impact process.The conclusion is drawn that vertical water-entry with minimum velocity is the most safe condition for the nose cap.Taking this condition as the upper limit of the nose cap strength design,key factors that may induce nose cap crack are analyzed.Accordingly,two methods to make the nose cap easy to crack after water-entry are offered,i.e.weakening the strength of the fairing and reducing the friction between the nose cap assembly and tor-pedo.Simulation results show that combination of two methods can achieve perfect nose cap water-entry.