Dual-Impulse Cartridge Launch Method for Large-Caliber Short Tubes

Large-caliber short launch tubes are gaining popularity in multiple offensive and defensive applications. Ensuring complete combustion of propellant at low chamber pressure, within a shorter reaction time, and over a shorter travel length is a critical yet challenging requirement for these systems. To reconcile these competing requirements, a specialized propulsion system is necessary. This paper proposes a novel technique that uses dual-impulse cartridges in a tandem configuration for launching large-caliber projectiles. A computationally efficient low-order interior ballistic relation is developed using a ballistic lumped-parameter model. A typical launch velocity is chosen based on the weaponry requirements. Four distinct configurations of the propulsion system are numerically investigated. Two configurations having a high-pressure utilization factor are experimentally evaluated. A good match is observed between the predicted and measured pressures and velocity data. A significant reduction in maximum chamber pressure with a marginal reduction in launch velocity is observed when compared to the standard single-cartridge configuration, resulting in a substantial decrease in the mass of the launch tube and the recoil force generated during launch. This work guides the design of interior ballistic propelling charges and demonstrates the feasibility of employing a dual-cartridge configuration to achieve the desired pressure plateau in short launch tubes.