LNG卫星站自增压时间影响因素研究

Study on influence factors of self-pressurization time in LNG satellite station

关键词:  LNG卫星站  自增压时间  遗传算法  低温液体储存模型  有限差分

Key words:  LNG satellite station  self-pressurization time  genetic algorithm  cryogenic liquid storage model  finite difference

摘要:

LNG卫星站主要采用自增压的液体增压方式,其自增压能力大小主要取决于增压时间。以LNG卫星站储罐作为研究对象,对比4种低温液体无损储存热力学模型,选择三区模型进行计算,采用一阶向前差分实现方程离散化,并基于遗传算法进行程序设计,进而计算得到了不同储罐起始压力、储罐充满率以及增压气体温度下的储罐增压时间变化。结果 表明,随着储罐所需压力上升,3种因素对储罐增压时间的影响效果有着不同程度的提升,其中储罐充满率对增压时间影响较为明显,最高可缩短78.4%的增压时间。 

Abstract:

The self-pressurization of liquid pressurization mode is widely applied in LNG satellite station, the self-pressurization ability of which depends on the required self-pressurization time. Taking the LNG satellite station as objective, four thermodynamic models for non-destructive storage of cryogenic liquids are compared and the Three-Zone model is selected for calculation. Based on the genetic algorithm, the program is designed to calculate with the equation discretized in the way of the first order forward difference and the change of required self-pressurization time in different tank initial pressure, initial filling rate and the temperature of self-pressurization gas are obtained. The results show that with the increasing required pressure of the tank, the effect of these three factors on the self-pressurization time of the tank increases in different degrees, in which the filling rate of the tank has an obvious effect on the self-pressurization time, and the time can be shortened by 78.4% at most.