New Type Tube-insert Heat Transfer Enhancement And Its Design Optimization Research

The conversion and utilization of energy is the basic activities of humanproduction and living. With the rapid development of society, due to the limitednumber of non-renewable resources and the associated environmental pollution、energy wastage and other negative effects when it’s exploited and utilized, it hasbecome negative factors of restricting the social healthy development, while improvethe efficient usage of energy is a feasible means for building a conservation-mindedand environment-friendly society.Much energy transferred and utilized by social production and living isappeared in the form of heat. The three basic modes of heat transfer are heatconduction, heat convection and heat radiation; different heat transfer modes followtheir own heat transfer law. In many cases, they are all in the way of compound toheat transfer. For single-phase convection heat transfer and energy exchange, whenthe temperature is not high, the quantity of heat transferred by other forms is limitedwhich can be ignored. Convective heat transfer fluid flow must be constrained withinthe channel which has a certain structure and shape, it can change the flow, improvethe ability of heat transfer by inserting the objects with different structure andfunction into the channel, thus tube inserts has been becoming the hot filed of heattransfer enhancement research.Based on researching and analyzing on in-tube heat transfer enhancing theoryand technology at home and abroad, using the former people’s achievements forreference, synthesizing the theory of Field Synergy and enhancement in the coreflow in this article, through adopting by different parameters to characterize thestructure of the components with the method of mathematical description, acyclone cross type heat transfer enhancing components was innovatively designed.In order to research and analyze the structure of the new design, firstly four factorsand four levels orthogonal test plan is designed by applying orthogonal test optimum design methodology, then determine the primary and secondary relations of variousstructures affecting heat transfer ability by analyzing and validating numericalsimulation of the cyclone cross type heat transfer components, and finally get threekinds cyclone cross type heat transfer components with different structure parametercombination, which are Nusselt numbers、Rsistance coefficient and PEC index. Theyare not only the optimal level combination structure, but also the important index tomeasure the quality of heat transfer enhancement.Meanwhile, in order to intensive study the heat transfer mechanism of crosstype heat transfer components and the similarities and differences of its structurecharacteristics for further developing and optimizing the cross type heat transfercomponents, through analyzing the different flow velocity of these three kinds ofcross type heat transfer components in laminar and turbulent flows state, we get theregularity of heat transfer ability in different flow states in this article.Simultaneously, from the microscopic view, the temperature、pressure and flowfield of the fluid after insert the heat transfer enhancing component is analyzed andresearched for putting forward improvements in future optimizing cross type heattransfer enhancement.