﻿ 高压气动装置弹射性能分析及优化
 舰船科学技术  2024, Vol. 46 Issue (5): 185-189    DOI: 10.3404/j.issn.1672-7649.2024.05.035 PDF

Analysis and optimization on ejection performance of high-pressure pneumatics system
ZHANG Hui-yi, JING Dong-feng, WANG Xin-liang
Wuhan Second Ship Design and Research Institute, Wuhan 430205, China
Abstract: According to the operating principle and characteristics of high-pressure pneumatics ejection system, three kinds of ejection devices are given, including ejection system standalone, ejection system with cushion chamber and ejection system with high-speed on-off valve. Interior ballistics model is established using aerodynamics theory and segmentation modeling method. On the basis, different parameters on leaving velocity and max-overload are calculated and analyzed. The simulation results show that, ejection system with cushion chamber and ejection system with high-speed on-off valve can both effectively reduce max-overload and increase leaving velocity. The best scheme is the one with high-speed on-off valve. The research production can guide the optimum design, manufacturing and experiment of high-pressure pneumatics ejection system.
Key words: high-pressure pneumatics     eject     cushion chamber     high-speed on-off valve     optimization
0 引　言

1 工作原理

 图 1 高压气动弹射装置工作原理 Fig. 1 Operating principle of high-pressure pneumatics ejection system

 图 2 含缓冲腔的高压气动弹射装置工作原理 Fig. 2 Operating principle of high-pressure pneumatics ejection system with cushion chamber

 图 3 采用多组高速开关阀的高压气动弹射装置工作原理 Fig. 3 Operating principle of high-pressure pneumatics ejection system with high-speed on-off valve
2 数 学 建 模

1）工作介质为理想气体，气体流动和弹射体运动是一维轴向运动；

2）压缩气体在工作过程中某一瞬时的压力、密度、温度都均匀分布；

3）忽略气体余容的影响；

4）高压气瓶内压缩气体经高压通道流入气膛区并推动弹射体出膛的过程在短时间完成，故认为是绝热过程，忽略气体与容器及通道壁面热交换；

5）不考虑气体的粘性，忽略通道壁面摩擦；

6）对弹射体弹射运动时的空气阻力、膛壁对弹射体的摩擦阻力修正，修正系数为α

7）气体比热比（绝热指数k）在整个过程中不随之改变，是定值；

8）气阀阀口在瞬间完全开启。

1）高压气瓶放气方程

 \begin{aligned} &{Q_1} =\\ & \left\{ \begin{gathered} {A_1}\sqrt {k{{\left( {\frac{2}{{k + 1}}} \right)}^{\frac{{k + 1}}{{k - 1}}}}P_1^{\frac{{k + 1}}{k}}\frac{{{\rho _{10}}}}{{P_{10}^{\frac{1}{k}}}}} \frac{{{P_2}}}{{{P_1}}} < {\left( {\frac{2}{{k + 1}}} \right)^{\frac{k}{{k - 1}}}}，\\ {A_1}\sqrt {\frac{{2k}}{{k - 1}}P_1^{\frac{{k + 1}}{k}}\frac{{{\rho _{10}}}}{{P_{10}^{\frac{1}{k}}}}\left[ {{{\left( {\frac{{{P_2}}}{{{P_1}}}} \right)}^{\frac{2}{k}}} - {{\left( {\frac{{{P_2}}}{{{P_1}}}} \right)}^{\frac{{k + 1}}{k}}}} \right]} \frac{{{P_2}}}{{{P_1}}} \geqslant {\left( {\frac{2}{{k + 1}}} \right)^{\frac{k}{{k - 1}}}}，\\ \end{gathered} \right. \end{aligned} (1)

2）高压气瓶内绝热状态方程

 $\frac{{{T_{10}}}}{{{T_1}}} = {\left( {\frac{{{P_{10}}}}{{{P_1}}}} \right)^{\frac{{k - 1}}{k}}}，$ (2)

3）高压气瓶内气体质量守恒方程

 ${m_1} = {m_0} - \int_0^t {{Q_1}} {\mathrm{d}}t，$ (3)

4）缓冲区放气方程

 \begin{aligned} & {Q_2} = \\ & \left\{ \begin{gathered} {A_2}\sqrt {k{{\left( {\frac{2}{{k + 1}}} \right)}^{\frac{{k + 1}}{{k - 1}}}}P_2^{\frac{{k + 1}}{k}}\frac{{{\rho _{20}}}}{{P_{20}^{\frac{1}{k}}}}} \frac{{{P_3}}}{{{P_2}}} < {\left( {\frac{2}{{k + 1}}} \right)^{\frac{k}{{k - 1}}}}，\\ {A_2}\sqrt {\frac{{2k}}{{k - 1}}P_2^{\frac{{k + 1}}{k}}\frac{{{\rho _{20}}}}{{P_{20}^{\frac{1}{k}}}}\left[ {{{\left( {\frac{{{P_3}}}{{{P_2}}}} \right)}^{\frac{2}{k}}} - {{\left( {\frac{{{P_3}}}{{{P_2}}}} \right)}^{\frac{{k + 1}}{k}}}} \right]} \frac{{{P_3}}}{{{P_2}}} \geqslant {\left( {\frac{2}{{k + 1}}} \right)^{\frac{k}{{k - 1}}}} ，\end{gathered} \right. \end{aligned} (4)

5）缓冲区绝热状态方程

 $\frac{{{T_{20}}}}{{{T_2}}} = {\left( {\frac{{{P_{20}}}}{{{P_2}}}} \right)^{\frac{{k - 1}}{k}}}，$ (5)

6）缓冲区气体质量守恒方程

 ${m_2} = {m_{20}} + \int_0^t {{Q_1}} {\mathrm{d}}t - \int_0^t {{Q_2}} {\mathrm{d}}t，$ (6)

7）气膛区绝热状态方程

 $\frac{{{T_{30}}}}{{{T_3}}} = {\left( {\frac{{{P_{30}}}}{{{P_3}}}} \right)^{\frac{{k - 1}}{k}}} ，$ (7)

8）气膛区气体质量守恒方程

 ${m_3} = {m_{30}} + \int_0^t {{Q_2}} {\mathrm{d}}t，$ (8)

9）弹射体运动方程

 $\frac{{{{\mathrm{d}}^2}}}{{{\mathrm{d}}{t^2}}}x = \frac{{{A_3}\left( {{P_3} - {P_{atm}}} \right) - mg}}{{\alpha m}} 。$ (9)

 $\frac{\rm{d}}{{{\rm{d}}t}}{P_1} = - k\frac{{{Q_1}}}{{{m_{10}}}}P_{10}^{\frac{1}{k}}P_1^{\frac{{k - 1}}{k}} 。$ (10)

 $\frac{{\rm{d}}}{{\rm{d}t}}{P_2} = k\frac{{\left( {{Q_1} - {Q_2}} \right)}}{{{m_{20}}}}P_{20}^{\frac{1}{k}}P_2^{\frac{{k - 1}}{k}} 。$ (11)

 $\frac{{\mathrm{d}}}{{{\mathrm{d}}t}}{P_3} = \frac{{k\left[ {\dfrac{{{Q_2}}}{{{A_3}{\rho _{30}}}}P_{30}^{\frac{1}{k}}P_3^{\frac{{k - 1}}{k}} - {P_3}\dfrac{{{\mathrm{d}}x}}{{{\mathrm{d}}t}}} \right]}}{x}。$ (12)

3 计算与分析 3.1 主要参数影响分析

 图 4 高压气瓶压强、高压气瓶容积、气阀通径对弹射体出筒速度的影响 Fig. 4 Impacts of tank pressure, tank volume, and latus rectum of air valve on leaving velocity

 图 5 高压气瓶压强、高压气瓶容积、气阀通径对弹射体最大瞬时过载的影响 Fig. 5 Impacts of tank pressure, tank volume, and latus rectum of air valve on max-overload

3.2 缓冲腔的影响分析

 图 6 采用缓冲腔前后高压气瓶压强对出筒速度的影响 Fig. 6 Impacts of tank pressure on leaving velocity in systems with and without cushion chamber

 图 7 采用缓冲腔前后高压气瓶压强对最大瞬时过载的影响 Fig. 7 Impacts of tank pressure on max-overload in systems with and without cushion chamber

 图 8 采用缓冲腔前后高压气瓶容积对出筒速度的影响 Fig. 8 Impacts of tank volume on leaving velocity in systems with and without cushion chamber

 图 9 采用缓冲腔前后高压气瓶容积对最大瞬时过载的影响 Fig. 9 Impacts of tank volume on max-overload in systems with and without cushion chamber

 图 10 采用缓冲腔前后气阀通径对出筒速度的影响 Fig. 10 Impacts of latus rectum of air valve on leaving velocity in systems with and without cushion chamber

 图 11 采用缓冲腔前后气阀通径对最大瞬时过载的影响 Fig. 11 Impacts of latus rectum of air valve on max-overload in systems with and without cushion chamber

 图 12 采用缓冲腔前后高压空气质量流量 Fig. 12 Mass flow in systems with and without cushion chamber

3.3 多组高速开关阀的影响分析

 图 13 各弹射方案对弹射过载的影响 Fig. 13 Impacts of various ejection schemes on max-overload

4 结　语

 [1] 赵希欣, 高元楼. 一种气体炮的建模与分析[J]. 液压气动与密封, 2012(10): 43-44. [2] 胡艳岭. 气动枪械发射原理有关问题的研究[D]. 南京: 南京理工大学, 2008. [3] 仲伟君, 赵晓利, 齐杏林. 气体炮内弹道建模与发射环境模拟研究[J]. 动力学与控制学报, 2005, 3(1): 62-66. DOI:10.3969/j.issn.1672-6553.2005.01.013 [4] 赵俊利, 曹锋. 气体炮实用内弹道方程及应用[J]. 火炮发射与控制学报, 2003(3): 48-51. [5] 赵俊利, 高跃飞. 气体炮实用内弹道技术研究[J]. 太原理工大学学报, 2003, 34(3): 288-290. [6] 夏正友, 张河, 陈家安. 一种非火药驱动气体炮内弹道模及发射诸元协调[J]. 爆炸与冲击, 1999, 19(2): 146-150.