基于时间序列分析方法对安全壳泄漏率测量阶段的气体弛豫过程研究

Study on Gas Relaxation Process in Leakage Rate Measurement Stage of Containment Test Based on Time Series Analysis Method

安全壳试验期间安全壳内气体在泄漏率测量平台经历了温度、蒸汽分压等参数波动并再次进入平稳的弛豫过程,本文针对判断新稳态建立的标准、气体弛豫时间、影响弛豫过程的因素等内容进行分析,以期通过计算检验统计量进行平稳性检验的方法给出判断平稳的标准,并对弛豫过程中各项参数的时间序列进行序列分解,对各参数的弛豫过程分别进行分析。研究结果表明,安全壳内气体因安全壳加压造成的蒸汽分压不均匀是影响弛豫时间的主要因素。因此,进一步提出控制蒸汽分压不平衡势,以缩短泄漏率结果的弛豫时间。

During the containment test,upon the leakage rate measurement plateau,the temperature,steam partial pressure,and other parameters of gases in the containment fluctuate and then go into the steady relaxation process.This article analyzes the criteria for reaching new steady state,the gas relaxation time,the factors that affect the relaxation process and other aspects to provide the criterion for steady state by performing steady state test via test statistic calculation.Also,this article conducts time series decomposition for various parameters involved in the relaxation process to analyze the relaxation process of each parameter separately.As seen from the study results,the relaxation time is mainly affected by the non-uniform steam partial pressure due to containment pressurization.On this basis,this study further proposes controlling the steam partial pressure imbalance trend to shorten the relaxation time of the leakage rate results.