Abstract: In order to study the influence of thermal effect of small caliber rifle barrel on barrel performance under the action of thermal load and surrounding parts, the difference between the temperature field and thermal deformation field of barrel with or without surrounding parts on the barrel surface is studied. Based on the initial conditions and thermal boundary conditions, a three-dimensional thermal-structure coupling model of gun barrel and surrounding parts under the thermal action of high-temperature gunpowder gas is established using finite element analysis software ANSYS. The thermocouple was fixed on the surface of barrel, and the temperatures at 10 positions on the barrel surface were measured. The simulated results are basically consistent with the experimental results. The simulated results of temperature field and thermal deformation field show that there is obvious heat absorption phenomenon in the direct contact area between the surrounding parts and the barrel surface, and the temperature field of barrel is asymmetric due to the structure of the surrounding parts; the radial inner diameter of barrel increases, and expands unevenly along the axial direction; the radial axis of barrel deviates and shows an uneven deviation along the axial direction. The research and analysis of barrel thermal effect under the action of thermal load and surrounding parts can lay a foundation for the later optimization of gun temperature field and the improvement of firing accuracy.

Key words: smallcaliberrifle, barrelthermaleffect, temperaturefield, thermaldeformationfield