Strength and Modal Analysis of a Gun Barrel under Four Different Strength Theories

Abstract The barrel with reasonable strength and vibration characteristics needs to be designed for safe and high accuracy firing. The finite element simulation analysis of a gun barrel based on the pressure-length curve load that calculated based on interior ballistic is carried out. Then the strength analysis and modal analysis of the barrel are carried out respectively. The twin shear strength theory is introduced into the design of barrel structure, and barrel elastic ultimate strength analysis method based on the twin shear strength theory is deduced in this paper. The barrel elastic ultimate strength along with the ratio of outer diameter and inner diameter according to three kinds of classical strength theory (i.e., the second, Tresca, and Mises strength theory) and twin shear strength theory were contrasted and analyzed, respectively, and the structural strength of the barrel and corresponding safety coefficient were checked and contrasted based on four different strength theories. The results show that the twin shear strength theory is the most appropriate theory for the design of the barrel. Under the same strength condition, the ratio of outer diameter to inner diameter of the barrel designed by this theory is smallest, and the weight of the barrel is the smallest. The barrel that design based on the twin shear strength theory was safer and not overweight. It also avoids the resonance frequency range and will not cause the occurrence of structure resonance phenomenon.