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China and even in the economic development of countries around the world is an important part of energy conservation has become a practical and efficient heat transfer enhancement technology is an important means of energy-saving , widely used in the field of petroleum, chemical , energy , metallurgy and materials engineering . In addition , there are a broad range of applications in the aerospace , electronics cooling , and safe utilization of nuclear energy and other fields . Therefore , the development of new types of enhanced heat transfer technology, the development of highly efficient heat exchanger can bring huge economic and social benefits . First, this paper based on the core flow strengthen the design principles of heat transfer principles , design mixing elements of the framework in the form of a polygon . And its numerical simulation to examine the performance of heat transfer , resistance characteristics and heat transfer enhancement of overall performance , the last field synergy principle analysis of the calculation results . The results show that strengthen the tube internal turbulent convective heat transfer : this can be in the form of interpolation was significant compared with fluorescent tubes , the spoiler element of added , so that the temperature of the tube internal central area being more evenly distributed , which greatly improve the effect of convective heat transfer , Nu number increased by 1.4 to 2.8 times ; drag coefficient f increased six-fold from 1.26 to 1.92 ; PEC . Then interpolated objects in a leaf-shaped tube heat exchanger strengthening effect simulated , and its heat transfer performance analysis of different structural parameters ( blade pitch , blade pitch ) . From the calculation results , such a structure in the form of an insert tube internal turbulent convective heat transfer significantly enhanced . The best model the effect of inclination of 30 ° , compared with fluorescent tubes , Nu number increased about 2 times the drag coefficient f an increase of about 10 times , comprehensive performance indicators the PEC to 1.6 to 2 . Finally, based on the object inserted within the leaf-shaped , its blade shapes for design improvement, to obtain a new sectorial blade inserted . Material strengthening effect of heat transfer through the numerical simulation , the comparison of the two forms of Vane interpolation . As compared with leaf-shaped interpolation improved fan blades plug flow resistance is smaller , the maximum value of the drag coefficient f decreased from 0.5 to 0.37 . Meanwhile , the effect of heat transfer are not obvious decline , from 424 down to 400 , PEC value has increased .
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