基于高频电磁阀的粉末推进剂质量流率控制规律研究

Research on the rule of powdered fuel flow rate control based on high frequency solenoid valve

基于气压驱动活塞、气流夹带流化的粉末推进剂供给方案,结合高频电磁阀的脉冲工作原理,提出了一种可实现粉末推进剂质量流率调节的控制方法。通过实验研究了不同电磁阀工作频率、占空比等参数对粉末推进剂流量调节特性的影响规律。结果表明,可通过电磁阀工作频率的变化进行粉末推进剂质量流率的调节,在背压0.6 MPa、工作频率5 Hz的情况下,活塞的最大位移速度为7.79 mm/s,为开关频率15 Hz时的1.98倍。背压0.42、0.83 MPa情况下,电磁阀正常工作的临界占空比分别为0.3、0.4。通过改变电磁阀的占空比,可实现粉末推进剂质量流率调节,占空比越大,调节能力越来越小,背压0.42、0.83 MPa情况下,活塞位移速率调节比分别为2.79和2.68,活塞位移速度最大值都处于占空比为0.8的情况下,分别为27.3、6.7 mm/s。

Based on the gas driven piston and airflow fluidized powder propellant supply scheme, by combination of pulse operating principle of high-frequency electromagnetic valve, a thrust regulation control scheme that can realize regulation of powdered fuel flow rate has been proposed. The effects of operating frequencies and duty ratios of the solenoid valves on the flow regulation characteristics of the powder propellant feeding device have been studied experimentally. The results show that the powdered fuel flow rate can be adjusted by changing the working frequency of the valve. Under the condition of 0.6 MPa surrounding pressure, the maximum displacement velocity of the piston at 5 Hz is 7.79 mm/s, which is 1.98 times higher than that at 15 Hz. The critical duty ratio of the valve under pressure of 0.42 MPa is 0.3, which is 0.4 at pressure of 0.83 MPa. By changing the duty ratio of the valve, the powdered fuel flow rate can be adjusted. The larger the duty ratio is, the smaller the regulating capacity is. In the cases of 0.42 MPa and 0.83 MPa, the piston displacement rate regulation ratios are 2.79 and 2.68, respectively. The maximum displacement velocities of piston at both ratios achieve 27.3 mm/s and 6.7 mm/s when the duty-free ratio is 0.8.