中文摘要：

超级开架式气化器（super open rack vaporizer,SuperORV）一类以海水作为加热热源的新型气化器,在LNG接收终端中得到了广泛应用。该气化器由具有双层套管结构的传热管屏组成,具有良好的传热特性。目前对SuperORV传热管的研究较少,对其强化传热机理认识不足,尤其是尚无对超临界压力下SuperORV传热管的传热特性研究。本文针对SuperORV传热管气化段和加热段的传热过程,建立了基于能量平衡方程的分布参数模型。通过上述模型对SuperORV传热管在超临界压力下的传热特性进行了数值计算及分析,并讨论了运行参数以及强化传热措施对其传热特性的影响规律。计算结果表明：SuperORV传热管在超临界压力下具有良好的传热特性,能够有效抑制表面海水结冰并提高LNG气化效率。LNG进口流量、LNG流量分配比、海水/LNG流量比对传热特性（传热管长度、结冰长度和冰层平均厚度等）影响较大,但系统运行压力对其影响较小。采用内翅片和螺旋纽带能够有效强化传热并提高传热管的传热性能。在上述两种强化传热措施同时应用时,传热管最小长度缩短了40%以上。

英文摘要：

Super open rack vaporizer（SuperORV） is a new-type vaporizer using sea water as heat source,which is widely used in liquefied natural gas（LNG） receiving terminal.The vaporizer consists of panel-shaped heat transfer tubes with double tube structure,which has good heat transfer performance.At present,due to a lack of in-depth studies on SuperORV heat transfer tube,the heat transfer enhancement mechanisms are still indistinct.In particular,the heat transfer performance at supercritical pressure hasn＇t been investigated.Aimed at the heat transfer processes in both vaporizing section and heating section of SuperORV heat transfer tube,in this paper a distributed parameter model was built based on the energy conservation between LNG and seawater.On this basis,the heat transfer characteristics of SuperORV heat transfer tube at supercritical pressure were calculated and analyzed numerically,and the effects of the operating parameters and the heat transfer enhancement measures（inner fins and twisted tape insert） on heat transfer performance were also discussed.The results exhibit that the SuperORV heat transfer tube has good heat transfer characteristics at supercritical pressure,which can apparently suppress icing on the tube surface and improve the LNG vaporizing efficiency.LNG flow rate and inlet distribution ratio,and seawater/LNG flow ratio have important influences on the heat transfer performance of heat transfer tube,including minimum tube length,ice layer length and ice thickness,whereas the operating pressure has little effect to heat transfer.Both inner fins and twisted tape insert have obvious enhancement in heat transfer and can effectively improve the heat transfer performance of SuperORV heat transfer tube.While both above-mentioned heat transfer enhancement measures were applied in SuperORV heat transfer tube,the required minimum tube length is shortened by more than 40%.