Numerical Simulation Study On Steam And Microwave Combined Heating Of Oil Tanker Cargo Oil

As a national strategic resource,oil is the foundation of sustainable social and economic development.With the continuous development of large-scale oil and gas field resources development,the number of cargo oil tankers has increased rapidly.It is necessary to heat and insulate the cargo oil in the oil tankers during navigation,so that they can be unloaded safely and quickly when docked.However,the traditional steam coil heating method has the problems of low thermal efficiency and large total fuel consumption,which will cause waste of energy and increase transportation costs of oil tankers.Microwave heating technology has the characteristics of fast heating,uniformity and high efficiency.It is widely used in the fields of petroleum exploitation and heavy oil viscosity reduction.Based on the microwave heating technology,this paper proposes a composite heating idea based on traditional steam coils and microwave-assisted heating,and analyzes the heat transfer of the composite heating process of cargo oil.The main research contents of the paper are as follows:Firstly,Based on the large cargo side tank as the prototype,the research object is cargo oil with high freezing point.This paper summarizes the heat transfer characteristics of cargo oil heating process at home and abroad,and determines the physical properties of the reduced oil by selecting appropriate dimensionless number.According to the Maxwell equations,energy conservation,mass conservation,momentum conservation and other differential equations,the heat transfer process of oil products in the heating process is described.The accuracy and reliability of the numerical model are determined by reasonably simplifying the scale model and verifying the accuracy of the numerical method.Secondly,the heat transfer variation law of the temperature field and velocity field of the compound oil heating process under normal temperature and static conditions was studied based on the selected numerical model.In addition,the heat loss and heat transfer efficiency of the oil in the cabin during heat transfer were analyzed by establishing an effective energy utilization evaluation index.Thirdly,the combined heating schemes with different power ratios are studied numerically,and the influence of microwave power on heat transfer efficiency is analyzed.Finally,the influence of different heating sequence on heat loss and heat transfer efficiency in the composite heating process is studied,in order to obtain a better energy-savingscheme for composite heating.The numerical results show that compared with the traditional steam coil heating method,the microwave composite heating process of cargo oil has a certain energy saving effect.In the heating process,if the microwave power is small,it will be beneficial to the endothermic heating of oil products and improve the average heat transfer efficiency of the heating process.In addition,microwave is used to heat the cargo oil in the upper area of the oil tank first,and then the steam coil is used to heat the whole cargo oil.This heating method can improve the heat transfer efficiency of cargo oil and reduce the heat loss in the process.