Mechanism Analysisand Calculation Of Heat Transfer In Internal Threaded Pipe With High Reynolds Number

The extensive application of internal threaded pipe in industrial boiler,the study of enhanced heat transfer mechanism and the calculation of heat transfer coefficient are of great significance for the application of internal threaded pipe in the field of high efficiency heat transfer technology and energy saving technology.In this paper,the internal thread pipe is the object of study,and the heat transfer mechanism and engineering thermodynamic calculation of the thread structure are studied in depth,including:Firstly,the flow mechanism and heat transfer characteristics of the fluid in the inner threaded tube are analyzed and explored.According to the turbulent flow of the fluid in the threaded tube under the condition of high Reynolds number,the fluid calculation model of the inner threaded tube under the high Reynolds number is established by using the relevant theory.Secondly,in view of the fact that the gas is the flow heat transfer medium in the internal threaded tube,four sets of empirical formulas that meet the requirements and are widely used in engineering are selected for the inductive arrangement.The Reynolds number is calculated to by replacing the Pr coefficient items in the empirical formulas with the high temperature air correlation test correlation formula4×10~4≦Re≦16×10~4The results obtained are compared,analyzed and evaluated in the range of 300℃≦T≦800℃,and the appropriate empirical formulas for heat transfer and flow resistance are selected under the condition of high Reynolds number.Finally,by using the widely used simulation ANSYS software in engineering,the three-dimensional modeling and mesh division of the inner thread tube are carried out,and the numerical simulation is carried out according to the flow heat transfer in the thread tube under different working conditions.Compared with the empirical calculation results,it is found that the simulation and calculation results are close to the trend of change under the condition of high Reynolds number,but there are still large errors in the specific values under each working condition.Through the analysis of the error reasons,the shortcomings of numerical simulation are summarized,which provides reference for the heat transfer research and calculation of threaded pipe.