在轨加注用超声波流量计的设计与试验

Design and Test of an Ultrasonic Flow Meter for Orbital Refueling

针对航天器在轨加注对推进剂流量的精确测量要求,研制了在轨加注用超声波流量计。在对传播时间法研究的基础上,提出流量计管路布局的设计要求,采用计算流体动力学(Computational Fluid Dynamics,CFD)的方法模拟4种不同管路布局(直角型、45°锐角型、直线型和圆弧型)对流体速度分布的影响,对比得到了优化的管路布局。信号处理电路使用斩波稳定比较器,通过阈值比较法,保证了传播时间的测量精度。流量计经标定后,在量程(0～150g/s)范围内可达到0.1%的测量精度。为了验证在轨加注过程中流量计的作用,在地面环境下进行了在轨加注地面模拟试验,试验表明超声波流量计在推进剂在轨加注中使用是可行的和必要的。

An Ultrasonic Flow Meter （UFM） was designed for accurate propellant gauging. Based on the research of transit time measurement, the requirements for pipe structure design were proposed. Computational Fluid Dynamics （CFD） was used to simulate the velocity distribution of four different pipe structures, and an optimal pipe structure was designed based on the CFD result. Chopper stabilized comparator in the signal processing electronics ensured the time measurement accuracy by using the threshold value comparing technique. After calibration, the ultrasonic flow meter can achieve an accuracy of 0. 1~//00 for range 0~lS0g/s. In order to test the function of the flow meter in orbital refueling, a ground simulation experiment was carried out. The result of the ground simulation experiment shows that the implementation of ultrasonic flow meter is practical for orbital refueling and quite necessary for performance observation during the refueling process.