| In this study, we made a experiment on eight kinds of channels installed with different hole's baffle. We studied its characteristics of enhanced heat transfer and flow resistance. This article analyzed the influence of some parameters on channel's enhanced heat transfer and flow resistance. Such as Re, the hole's diameter with no unit d/1, level center distance with no unit sl/1 and vertical center distance s2/l etc. and compared the characteristics with the no hole baffle.The subject was relied mainly on experiment, and included the theory analyze. In the first, designed and set up the visual experiment equipments, and carried on the visual experiment, the characteristic of low Re flow was analyzed through injecting ink to the channel; Secondly, in order to analyzing channel fluid conduct heat mechanism of strengthening further, heat transfer and fluid flow experiment study device was designed and set up, and carried on the experiments under the equal heat flux border situation. When in experiment, the air was heated by the film heater installed on the above and below surface of channel, adopting various air velocity of flow, test import's and export's temperature, wall temperature, fluid flux and the drop of pressure, and the other parameter. Adopting Nu and Nu0 to analyze the baffle's situation of heat transfer and fluid flow, which baffle was holed various diameters.The results indicated with the Re raising, the rectangle channel's heat transfer enhanced gradually, which channel installed the baffle on its above and below. Moreover, compared with the channel with no hole baffle, the channel with hole's baffle, because the change of structure of the baffle, flow resistance reduced, the drop of flow pressure reduced as follow, the d/w, sl/w and s2/w also influenced the channel's heat transfer. In the test, the d/w has three values: 0.2 0.13 and 0.7, we used the ratio of Nu to NU0 to analyze the characteristics of the channel's heat transfer, used the ratio of f to f0 to analyze the characteristics of the channel's flow resistance. Through the efficiency η (the η was defined the ratio of Nu/Nu0tof/fo)we measure the influences of different infinitude date on the channel's heat transfer, we found the results of the heat transfer: No 3 baffle is the best, No 5 baffle is better than model 8. In the study, sl/w has two values: 0.67 and 1.33. Used the method of analyzing the influence of d/w on the channel's heat transfer and flow resistance, we found the results of the heat transfer: No 3 baffle is better than No 5 baffle. In the same way, we could analyze the two values 0.25 and 0.33 of the s2/w, we could find that: No 3 baffle is better than No 2 baffle.Based on the experiments result, we found that the integrated of the No 2 baffle is the best. The local Nu of the No 2 baffle was studied, the results indicated that with the liquid flowing in the channel, the distance increase continuously, The local Nu of the No 2 baffle fluctuated. From up to down, and from down to up.This study got a lot of test data about the characteristic of enhanced heat transfer and flow resistance. It has reference value to the different kind of heat exchanger. Furthermore, At the end of the article we made the poly-line return on many experimental condition , get the-standard experimental connected equation, provided basic data and design basis for the apply of this new type of heat exchange...
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