摘要: |
经典液滴蒸发模型无法适用于LNG制冷剂在其蒸气中的蒸发过程模拟。采用数值模拟方法,建立静止饱和甲烷液滴在其蒸气中蒸发的新模型。利用该模型对液滴蒸发过程进行计算。结果表明:模型计算结果准确可靠;气液界面蒸气喷出速度与液滴半径成反比,与温差成正比;“吹拂效应”使温度边界层变厚,热流密度减少;温差为190 K、半径为0.5 mm工况下,“吹拂效应”影响最剧烈,使温度边界层增厚28.8%,热流密度减小27.7%;质量蒸发率随温差以及半径增大而增大且与半径、温差之间具有一定的数学关系。 |
关键词: 液化天然气 传热传质 液滴蒸发 温度边界层 数学模拟 |
DOI:10.3969/j.issn.1673-5005.2019.06.016 |
分类号::TK 124; TE 88 |
文献标识码:A |
基金项目:国家自然科学基金青年基金项目(11602222);浙江省基础公益研究计划项目 (LY18E090009);浙江省舟山市科技局项目(2016C41021,6C12010);浙江海洋大学科研启动基金项目(Q1612) |
|
Simulation and analysis of evaporation of stationary saturation liquid methane droplet in its vapor |
DENG Jiajia1, XU Jian2, LU Jinshu1
|
(1.School of Port and Transportation Engineering, Zhejiang Ocean University, Zhoushan 316022, China;2.School of Naval Architecture and Mechanical-electrical Engineering, Zhejiang Ocean University, Zhoushan 316022, China)
|
Abstract: |
The classic models for the droplet evaporation are often difficult to predict the evaporation of a liquid methane droplet during the cooling down of a cargo tank. A novel evaporation model to overcome the difficulties was presented. With different temperatures, the evaporation processes of droplets with different sizes were systematically investigated. The results show that the calculation results of the current model are accurate and reliable. The velocity of the vapor at the gas-liquid interface is inversely proportional to the droplet radius and proportional to the temperature difference. The "blowing effect" makes the temperature boundary layer thicker and the heat flux decreased. Under the temperature difference of 190 K and the radius of 0.5 mm, the “blowing effect” has the most severe influence, i.e. the temperature boundary layer is thickened by 28.8%, and the heat flux is reduced by 27.7%. The mass evaporation rate increases with the increase of the temperature difference and the radius, which is correlated with the radius and temperature difference with a certain mathematical relationship. |
Key words: liquefied natural gas heat and mass transfer droplet evaporation temperature boundary layer mathematical simulation |