超临界CO_(2)临界流稳态试验研究及模型验证  

Experimental Study on Critical Flow of Supercritical CO_(2)at Steady State and Model Verification

作　　者：李伟卿[1] 张东旭[1] 赵民富[1] LI Weiqing;ZHANG Dongxu;ZHAO Minfu(Reactor Engineering Technology Research Institute,China Institute of Atomic Energy,Beijing 102413,China)

机构地区：[1]中国原子能科学研究院反应堆工程技术研究所,北京102413

出　　处：《原子能科学技术》2022年第8期1593-1598,共6页Atomic Energy Science and Technology

基　　金：国家重点研发计划(2018YFE0116100)。

摘　　要：反应堆发生破口事故时,由于堆内处于高温高压状态而外界压力很低,破口处可能出现临界流动现象,临界流动特性对事故进程有较大影响,破口临界流量的准确估算对超临界水堆的安全分析更为重要。针对喷放为两相流动的工况范围,以超临界CO_(2)为工质,采用直径2 mm、长径比1~20的喷管试验段在超临界压力下开展了临界流稳态试验,获得了系统可靠的试验数据,研究了滞止压力、滞止温度以及喷管长径比对临界流量的影响。使用获得的超临界CO_(2)试验数据验证了临界流热平衡通用模型的通用性和准确性,发现其可以较好地预测超临界工况下的临界流量。本文研究补充了临界流动试验数据库,为临界流模型的验证和改进积累了试验数据。When the loss of coolant accident happens in a reactor,because of the high temperature and high pressure in the reactor and the low external pressure,the critical flow may occur at the break due to sharp depressurization and vaporization.The critical flow characteristics have a great impact on the accident process,and the accurate estimation of critical flow at the break is more important for the safety analysis of the supercritical water reactor.In order to obtain the critical flow characteristics under supercritical conditions,the steady state tests of critical flow were systematically carried out under supercritical pressure in a nozzle test section with a diameter of 2 mm and a length diameter ratio of 1-20,taking supercritical CO_(2)as the working fluid.The test pressure range was 7.4-9.5 MPa and the temperature range was 15-55℃,a large number of reliable test data were obtained from the test.The effects of stagnation pressure,stagnation temperature and nozzle length diameter ratio on critical flow were obtained.That is,when the pressure is constant,the critical flow decreases with the increase of inlet temperature,and the critical flow drops sharply at the beginning,but when the inlet temperature is higher than a certain value,the critical flow changes little with the increase of stagnation temperature.The turning point of flow rate changing with temperature is about the pseudo critical temperature of the corresponding pressure.The higher the stagnation pressure,the greater the critical flow.The influence law of stagnation temperature and stagnation pressure on critical flow is basically consistent with the change law of critical flow of water.For short nozzle and medium long nozzle,the influence of length diameter ratio is small.For long nozzle,due to the greater influence of friction resistance,the flow is much smaller,but the higher the stagnation temperature,the higher the stagnation pressure,the smaller the influence of the length diameter ratio.The obtained experimental data complements the critical

关 键 词：超临界CO_(2) 失水事故 临界流 稳态试验 模型验证 

分 类 号：TL33[核科学技术—核技术及应用]