Study on the flow control of continuous post-spraying of gas-guide self-locking for weapon dispersed charging

Abstract. Excessive recoil severely restricts the application of high-power traditional guns on modern aircraft. The objective of the proposed dual-chamber dispersed charging high-pressure opening and low-pressure replying gas-guide self-locking control rear spray scheme is to address the shortcomings of existing lateral-nozzle weapons, which are unable to control the opening and replying of the rear spray channel. This results in the inefficient utilization of powder gas and a short duration of continuous rear spray. The scheme aims to further reduce the recoil impulse of the weapon by optimizing the opening and replying of the rear spray channel. In light of the two-phase flow of powder gas within the dual chamber, the gas-guide self-locking channel and lateral rear nozzle, coupled with the gas-solid coupling effect of the two spring-slider systems of the valve and the locking pin, a mathematical model is proposed. A model of the firing process of a 30 mm cannon with dispersed charging, gas-guide, and self-locking control rear spray has been established. The flow field in the two chambers and lateral rear nozzle, as well as the motion law of the valve and the locking pin, have been obtained. A further comparison is made with the firing process of a two-chamber weapon with a fixed-pressure valve, with the objective of analyzing the influence of the gas-guide self-locking control on the duration and total impulse of the powder gas post-spray. The results demonstrate that in comparison to existing dual-chamber fixed-pressure weapons, the dual-chamber gas-guide self-locking control post-spray weapon increases the post-spray duration from 4.682 to 7.434 ms, thereby extending the post-spray. The duration of the powder gas post-spray is increased by 58.78 %, while the total post-spray impulse rises from 414.12 to 454.77 N s. This results in a reduction of the weapon recoil impulse by 29.34 %. This study further reduces the weapon recoil impulse of the dual-chamber rear spray while simultaneously controlling the opening and resetting of the rear spray channel. This makes the design of the dual-chamber rear spray a more practical method of reducing the recoil impulse.