运载火箭贮箱多液位容积测量偏差与修正研究

Study on Deviation and Correction of Multiple Liquid Level Cubage Measurement in Fuel Tanks of Launch Vehicle

运载火箭燃料贮箱多液位容积主要采用基于流量计的测量方法。为提高贮箱多液位容积测量的准确性,将理论和试验相结合,研究了试验介质温度、压力、贮箱膨胀对容积测量结果的影响。结果表明:为避免贮箱容积偏差超过0.05%,应对容积测量时的温度变化进行控制或进行实时补偿;压力对密度的影响进而导致的容积偏差可以忽略,在0.4 MPa静水压力下,影响低于0.01%;基于现有设计和使用准则,光筒段贮箱的体积膨胀成为贮箱容积测量最主要的偏差来源,达到了0.1%的偏差量级,且随着贮箱气枕压力、液位高度、贮箱直径、试验介质密度的增加,其测量结果相对于空箱状态的偏差越大,必要时应针对不同试验介质进行修正。

Fuel tank cubage of launch vehicle is measured mainly based on the flowing method.The influences of temperature of the test medium,the pressure and the fuel tank expansion were studied theoretically and experimentally in this paper.The results showed that to control the deviation under 0.05%,the test medium temperature must be controlled or compensated in real⁃time.Density change caused by pressure change could be negligible,since there was only a 0.01%deviation with pressure change up to 0.4 MPa.Tank expansion with inner pressure approaching its designed pres⁃sure could cause above 0.1%deviation to liquid level cubage,and the deviation was amounted with the increment of fuel tank pressure,liquid level height,fuel tank diameter and test medium density,thus the correction of multiple liquid level cubage was necessary.