SCV耦合传热特性实验研究与数值模拟

摘要

浸没燃烧式汽化器(SCV)是液化天然气(LNG)接收站中一种必不可少的换热设备,主要通过水浴系统作为中间介质实现烟气与LNG之间的热量传递.搭建一套完整的SCV流动换热实验平台,对其内部复杂的传热特性进行研究.可视化实验结果揭示了汽化器内部一些独特的流体动力学现象(局部水浴结冰等),同时通过建立的气液两相混合物与跨临界LNG耦合传热计算模型得到了换热管束内外局部流体温度和局部传热系数分布曲线,并分析了LNG进口压力、LNG入口速度、初始水位高度以及烟气进气量对NG出口温度和水浴温度的影响规律.研究成果能够为SCV国产化设计提供重要参考.%Submerged combustion vaporizer is indispensable heat exchanger equipment for liquefied natural gas (LNG) receiving terminals, it mainly utilizes water bath system as intermediate media to achieve heat transfer between flue gas and LNG. In this work, an unabridged experimental apparatus is built to study the complex heat transfer characteristics of it. Experimental results reveal some unique fluid dynamic phenomena inside SCV system (local water bath freezes). Meanwhile, the simulated model is established for coupled flow and heat transfer process between two-phase mixture and trans-critical LNG. The influences of inlet LNG pressure, inlet LNG velocity, static water height, flue gas flux on the NG outlet temperature and water bath temperature are analyzed. The outcomes can provide some important guidance to localization design of SCV.