| With the continual decrease in the world's energy reserves, it has become more and more urgent for us to take effective energy-saving measures. In china, the energy utilization efficiency of the heat-exchanger equipments is relatively than of the advanced level. So, there are more potential in energy conservation of the heat exchange facilities, especially in the realm of the finned-tube, the enhancement of heat transfer on air-side has a long way to go. Ti has been proved, theoretically and experimentally, that perforating on the fin surface is a good way to enhance the heat transfer in the finned-tube with a perfect of energy conservation under dry condition. At the range of air flow velocity in the narrowest cross section from1 to 8 meter per second, the equivalent coefficient of heat transfer of the optimal holes finned-tube is higher by 22.6~30.4 percent than the plane finned-tube and, while the increase of pressure drop is under 8 percent. When the velocity is 0.5 meter per second, the experiment research show the cooling capacity of the holes finned-tube is higher by 6.02 percent, the heat convection coefficient of the surface is higher by 18.84 percent, and the heat transfer coefficient is higher by 11.53 percent in average during the frosting process than the plane finned-tube. The COP (coefficient of performance) of circle holes fin-tube heat exchanger is higher by 6.83 percent than the plane finned-tube, and saving energy is 6.39 percent.At present because the enhancement heat transfer researches of holes fins are only used the experiment under dry condition, the air-sides flowing and heat transfer of the plane finned-tube heat exchanger, the symmetrical holes finned-tube heat exchanger and the three symmetrical holes finned-tube heat exchanger in the paper. The distributions of the velocity, the temperature and the Nu(number of Nuselt) are analyzed. The modeling result is high agree with the experiment bates, the average error is less 10% with obtaining the best optimal kind of fin named three symmetrical holes'fin. Its average heat transfer coefficient is higher by 25.7% in average than the plane fin.Because experiment research is used the refrigerator with only the velocity value under frosting condition, so the experiment result can't reflect the enhancement heat transfer performance of the circle holes fin. A wind-tunnel system is built for testing the heat transfer and cooling performance of the plane finned-tube heat exchanger, the symmetrical holes finned-tube heat exchanger and the three symmetrical holes finned-tube heat exchanger. The cooling capacity, the average heat transfer coefficient and the resistance of the three kinds of finned-tube heat exchangers are compared and analyzed. The energy conservation effect of the heat enhancement fin is analyzed. The experiment results compared with the plane fins showâ‘ the heat enhancement effect of the fin of three symmetrical holes is the best, the max value of cooling capacity is higher by 16.7% and average value is higher by 9.1%.â‘¡the max average equivalent heat transfer coefficient is higher by 80.15%, the min value increases by 49.66%, and the average is higher by 64.29%.â‘¢the max value of COP is higher by 30.16%, the min value is higher by 14.95% and the average is higher 22.93%.In the end of the paper the comparative experiments between the variational space and the constant space of evaporator made of fins with perforating symmetrical holes are done. The experiment bates showâ‘ the average equivalent heat transfer coefficient of the variational space evaporator is higher 12.57%, the max value is higher by 18.26% and the min value is higher 9.4%.â‘¡with meeting the cooling capacity, the variational space finned-tube heat exchanger can saving materials by 21.43%, having the bright future in the energy conservation.
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