低温开架式气化器表面结冰数值模拟  

Numerical simulation of freezing on the surface of ORV

作　　者：孙启迪[1] 陈叔平[1] 姚淑婷[1] 赵拓[1] 金树峰[1] 刘德玉[1] 孟国亮[1] 

机构地区：[1]兰州理工大学石油化工学院,兰州730050

出　　处：《低温与超导》2016年第3期16-19,54,共5页Cryogenics and Superconductivity

摘　　要：针对开架式气化器(ORV)建立4组不同海水液膜厚度下的换热管模型,基于Realizable k-ε及Solidification&Melting模型进行流固耦合传热计算,分析不同海水液膜厚度以及不同海水入口流速对换热管外海水结冰的影响。海水入口流速在0.5m/s^1m/s范围内变化时,海水入口流速越小,液膜厚度越薄,换热管外海水越易结冰;当液膜厚度为1mm、海水入口流速为0.5m/s时,结冰长度达到454mm。可见,换热管外海水结冰受液膜厚度与海水入口流速影响很大。海水从上往下流动过程中,换热管外海水结冰率逐渐增大,冰层逐渐增厚,且结冰重点区域位于换热管翅片缝隙及换热管连接处。因此在ORV实际运行中,为防止换热管结冰,应合理布置海水分布装置,并对换热管外翅片夹角、形状及换热管连接结构进行优化设计,以增强ORV传热效果。The models of 4 sets of heat transfer tubes with different film thickness were established for ORV,the heat transfer calculation of fluid-structure interaction was done based on the realizable k-ε and solidification melting models,and the effects of different film thickness and different inflow velocity of seawater on freezing of seawater outside the tubes were analyzed.The inflow velocity of seawater varied from 0. 5m / s to 1m / s,the lower the inflow velocity,the thinner the film thickness,and the freezing of seawater outside the tubes became more easier. When the inflow velocity was 0. 5m / s,and the film thickness was1 mm,the maximum freezing length was 454 mm. Visibly,the freezing of seawater was greatly influenced by the inflow velocity and the film thickness. In the process of seawater falling,the volume fraction of ice increased,the ice layer became thicker gradually,and the obvious areas of icing lie in the gap of the fins and the joints of the tubes. In order to prevent the freezing of heat transfer tubes,the seawater distributor should be properly placed in the actual running of ORV,as well as the angle and shape of fins,and the joints of the tubes should be designed optimally,which could enhance the heat transfer efficiency of ORV.

关 键 词：结冰 数值模拟 开架式气化器 液膜厚度 

分 类 号：TQ545[化学工程—煤化学工程]