Analysis And Application Of Polar Low Temperature Effect On Temperature Field In Cargo Tank Of Oil Tanker

In recent years,the successful development of Arctic shipping routes has prompted people to gradually turn their attention to the oil heating and insulation technology of oil tankers in the Arctic region.However,due to the complexity of the polar environment,this research is still facing many difficulties.In order to avoid the difficulty of unloading due to the natural cooling and solidification of the cargo oil during the sea transportation of the polar tanker,the cargo oil must be heated and insulated.Compared with normal temperature environment,the temperature rise of cargo oil and the temperature field of tank are different in polar low temperature environment.Therefore,in order to further study the variation law of temperature field of cargo oil in oil tank under polar low temperature,this paper mainly takes heat transfer knowledge as the theoretical basis,and establishes a numerical model of tanker cargo tank with the help of finite element software Fluent.In this paper,the VLCC is taken as the reference object.According to the principle of heat transfer and the characteristics of oil viscosity and temperature,the working process of cargo oil convection heat transfer is studied with the help of equations.Using gambit,fluent and other numerical simulation software,scale numerical simulation and three-dimensional full-scale numerical simulation are established.Based on the goal of reducing boundary heat dissipation,a low-temperature environment control group is set up to carry out numerical simulation and obtain data such as temperature field,flow field,viscosity and flow pattern.The heat flux is calculated to determine the heat loss characteristics of crude oil in polar low temperature environment.In this paper,three groups of different ambient temperatures were set,respectively:273.15 K,263.15 K and 253.15 K.The difference of temperature rise and temperature field distribution of cargo tank under different ambient temperature is compared.The results show that the oil temperature increases from 306.15 K to 316 K when the ambient temperature is 273.15 K,and to 312 K and 310 K when the ambient temperature is 263.15 K and 253.15 K,respectively.That is,the lower the ambient temperature is,the greater the influence of the external environment on the temperature rise of cargo oil is,the slower the temperature rise of cargo oil is,and the lower the ambient temperature is,the greater the influence on the temperature field distribution of cargo hold is.The results show that the main heat transfer methods of oil are thermal conduction and heat convection in the process of heating and holding oil at normal temperature or polar low temperature.The heat transfer mode of cargo oil in direct contact with the heat source is heat conduction,and the heat transfer method of cargo oil between different oil temperatures without relative displacement is also heat conduction method.The heat transfer mode of cargo oil between cargo oil is natural convection only when the cargo oil at different oil temperatures has relative displacement.