Numerical Simulation And Optimization Research On Heat Transfer Tube Of SuperORV

SuperORV is a new type of vaporizer with advantages of green economy and a large quantity of gasification.It can effectively vaporize liquefied natural gas into natural gas by using the temperature difference between seawater and liquefied natural gas.However,the heat transfer performance on heat transfer tube of SuperORV are affected by both operating conditions and structural parameters which requires in-depth analysis and research.In this paper,the heat transfer performance on heat transfer tube of SuperORV was numerically simulated by Fluent.The main work is as follows:(1)The heat transfer performance on heat transfer tube of SuperORV were studied in depth under different operating conditions.The effect of total convective heat transfer coefficient under different the flow rate of LNG and seawater were studied,and it was found that the flow rate of seawater on the outside of the heat transfer tube had little influence on the total convective heat transfer coefficient,while the flow rate of LNG on the inside of the heat transfer tube had great influence on the total convective heat transfer coefficient.Changing the operating conditions inside the heat transfer tube had a significant effect on the heat transfer performance of the heat transfer tube.(2)The inner structural parameters of heat transfer tube were optimized.The different structure parameters(pitch size and number of plums)inside the heat transfer tube were simulated,the pitch size and number of plums on the inside of the twisted plate had great influence on the heat transfer performance.Under certain conditions,there were optimized values for pitch size and number of plums to significantly improve the heat transfer performance on heat transfer tube of SuperORV.The geometric model of the heat transfer tube with the best heat transfer performance was built and simulated,and the changes of LNG temperature distribution on the inside,seawater temperature distribution on the outside and total convective heat transfer coefficient on heat transfer tube of SuperORV were analyzed.It was found that the heat transfer performance on heat transfer tube of SuperORV was improved after optimizing the structure parameters.(3)The effect of different operating parameters on the heat transfer performance of heat transfer tube was studied.The flow rate of LNG had a great effect on the natural gas outlet temperature and the total convective heat transfer coefficient of heat transfer tube.With the decrease of LNG inlet flow rate,natural gas outlet temperature increased continuously,but the total convective heat transfer coefficient decreased.When the LNG inlet flow rate was 192t/h,natural gas outlet temperature was less than 0?,which did not met the operation requirements;When the LNG inlet flow rate dropt to 153.6t/h,natural gas outlet temperature was higher than 0?,which met the operation requirements.