Main Article Content
Internal ballistics examines the pressure from combustion gases. Internal ballistic analysis describes the amount of firing propellant, the amount of energy released to move the bullet, the pressure imparted to the interior of the bullet, the features of the barrel and its tolerance against pressure. The present paper uses a numerical method to predict internal ballistic parameters such as pressure, temperature, velocity and friction force along the weapon barrel. A grid was generated in the Gambit environment. Using the user-defined functions to apply the boundary conditions, the motion of the bullet inside the barrel is simulated in the FLUENT software environment, and its behavior is examined from the onset of motion due to combustion pressure until it is available. As the ultimate goal in internal ballistic analysis is range-proportional velocity, this paper describes the factors affecting the achievement of an optimal velocity. Also, the way a bullet travels down the barrel is shown using graphs and contours. The most important results include the upward and downward pressure followed by the temperature behind the bullet. Also, the maximum temperature was found to occur behind the bullet and its minimum in the bullet.