摘要
LNG作为清洁能源,有助于实现“碳达峰、碳中和”目标。LNG气化器是关键设备,其内部发生低温工质的流动沸腾。选用板壳式换热器作为气化器并开展试验研究,搭建了一套闭式低温传热与流动试验系统,测试温度为90~200 K,运行压力为100~3000 kPa,流量范围为1~24 g/s,功率达到8 kW,对于沸腾试验能够覆盖整个干度范围。系统用于流动沸腾和单相传热,同时进行传热和压降测试,适用于多种低温工质和换热器的组合。以LNG的主要组分甲烷进行饱和流动沸腾试验,研究了干度、热流对换热系数、两相压降的影响,测试干度范围为0.32~0.72,热流密度范围为3.2~6.4 kW/m^(2)。根据局部换热系数和局部壁面过热度,分析了圆形板壳式换热器对蒸干的抑制作用,为开展更大范围的低温试验奠定了基础。结果表明,现有公式无法准确预测LNG在板壳式换热器内的传热系数,需要扩展试验工况范围并提出新公式。
As a clean energy,LNG was conducive to achieve the goal of"carbon peak and carbon neutrality".The vaporizer of LNG was the key component,where the flow boiling of cryogenic fluids took place.A plate and shell heat exchanger was experimentally analyzed as a vaporizer.An experiment system of close cycle had been developed for the heat transfer and flow of cryogenic fluids.The test temperature was 90~200 K,the operating pressure was 100~3000 kPa,the flow rates was 1~24 g/s,the maximum heat capacity was 8 kW.The overall range of vapor qualities was covered for the flow boiling.The experiment system was used for flow boiling and single‑phase heat transfer,with the heat transfer and pressure drop measured simultaneously.The experiment system was suitable for the different combinations of cryogenic fluids and heat exchangers.The saturation flow boiling test was conducted using methane,the main component of LNG.The influences of vapor qualities and heat fluxes were investigated on the heat transfer coefficients and two‑phase pressure drop.The vapor qualities are 0.32~0.72,while the heat fluxes are 3.2~6.4 kW/m^(2).The circular plate and shell heat exchanger suppresses the dryout,which is analyzed according to the local measurements of heat transfer coefficients and wall superheating.This investigation lays the foundation for the further experiments of cryogenic experiments.The results indicate that the existing formulas are unable to accurately predict the heat transfer coefficient of LNG in plate and shell heat exchangers,necessitating the expansion of the experimental condition range and the proposal of a new formula.
作者
陶轩
吴童菲
谢梓芃
王思琦
迟浩淼
叶晶
栾辉宝
TAO Xuan;WU Tongfei;XIE Zipeng;WANG Siqi;CHI Haomiao;YE Jing;LUAN Huibao(Key Laboratory of Refrigeration and Cryogenic Technology of Zhejiang Province,Cryogenic Center of Hangzhou City University,Hangzhou 310015,China;Shanghai Marine Diesel Engine Research Institute,Shanghai 201108,China)
出处
《压力容器》
北大核心
2025年第7期30-37,共8页
Pressure Vessel Technology
基金
浙江省自然科学基金白马湖实验室区域创新发展联合基金项目(LBMHY24E060008)。
关键词
LNG气化器
板壳式换热器
流动沸腾
传热性能
两相压降
vaporizer of LNG
plate and shell heat exchanger
flow boiling
heat transfer performance
two‑phase pressure drop
