风洞供气控制系统数字阀的设计与应用

随着风洞供气试验所需的指标越发苛刻，模拟调节阀已经无法满足要求，同时针对目前PCM数字阀和PWM数字阀存在的缺陷，提出了一种PCM+PWM数字阀，通过PCM数字阀提供基准流量，PWM数字阀在基准流量的基础上再进行脉宽调节，以满足供气试验的要求。文中介绍了数字阀的研究现状、设计指标、喷嘴的类型选择和结构设计、喉道面积的分配、电磁阀参数计算和型号选择，以及基于PID的流量调节运算方法，并通过多次调试、优化参数，性能测试，最终开展了多项供气试验。试验结果表明，数字阀在风洞供气控制系统中的应用是成功的，试验流量绝对控制精度优于±3g/s，且响应时间短、调节范围宽和可靠稳定等特点为风洞供气试验提供了强有力的支撑。

Design and application of digital valve in gas supply control system for wind tunnel

As the required indicators of air supply experiments in the wind tunnel become more rigorous, the analog control valve is unable to meet the demands. Considering the drawback of PCM digital valve and PWM digital valve, the PCM+PWM digital valve is put forward to meet the gas supply requirements, where the PWM digital valve regulates the flow under the benchmark which is provided by the PCM digital valve. The research status and design index of the digital valve, the selection and design of the nozzle, the distribution of the throat area, the calculation and selection of the magnetic valve, and the flow control method based on PID are introduced in detail. By repeated debugging, parameters optimizing and performance testing, several gas supply experiments are conducted. Experimental results show that the application of the digital valve is successful, the measuring accuracy of the mass flow control is superior to ±3g/s, and the characteristics of fast response, large range, and high reliability are achieved to provide strong support for gas supply experiments.