| By analyzing how the streamwise vortices such as tip vortices and horseshoe vortex system grow,develop and enhance the heat transfer,the paper puts forward a new-style VG(Vortex Generator) ?the angle-cut elliptical column. Mean while , the method fixing geometrical structrure and size of the VG was discussed. It is supposed that both tip vortices and horseshoe vortex system are generated by the new-style VG to support the better heat transfer enhancement. What's more , it adopts streamline form at head-on location which reduces the resistance from the VG and minishes the flow loss.The experimental measuring system is set up and experimental studies are made on several VGs.The experiments include comparing work among several VGs and the optimizing reseach of the best one.Under the equal preconditions ,the effect of heat transfer enhancement and the flow loss are compared among some VGs such as delt winglet,trapeziform winglet,rectangular winglet,angle-cut cylindrical and elliptical column.The results show that the compositive effect of heat transfer enhancement by angle-cut elliptical column is the best.Although the rectangular winglet has almost the same effect as angle-cut elliptical column while enhancing heat transfer at the state of turbulent flow,it causes the biggest flow loss.which is as 3.5 times as of the other VG.So the experiments prove that angle-cut elliptical column is a kind of new-style VG with better heat transfer enhancement and lower flow loss.After that,the optimizing experiments are continued to study the optimal size and orientation of angle-cut elliptical column VG.The result shows that the effect of the VG is the best when the bevel edge angle- a equals 20 degrees and the angle of attack- P is 45 degrees under the experiment condation.At last,multipal-regerssion is done on the experimental data of angle-cut elliptical column,and the dementionless equations are given accordingly,which support the foundation for the engineering use of this new-style VG.
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