圆孔翅片管积霜工况下的制冷性能实验

实验研究证实,圆孔翅片管在无霜工况下的传热性能远优于平翅片管,但积霜工况下的传热与制冷性能是否优越没有得到实验验证.利用冰箱制冷系统,分别采用圆孔-半圆孔交叉翅片、圆孔翅片以及平翅片管式换热器,进行积霜工况下的传热和制冷性能对比性实验研究.考察了积霜过程对圆孔孔径大小的影响;分析比较了3种不同片型的有效制冷量、传热系数和实际制冷系数;比较了强化翅片的节能效果;采用有限元法求解出翅片效率,并分离求出实际对流换热系数,从而揭示了翅片表面的实际换热情况.结果表明:与平翅片相比,当最窄截面风速为0.5 m/s时,积霜工况下,圆孔翅片的传热系数平均提高了11.53%;对流换热系数平均提高了18.84%;实际制冷系数平均提高了6.83%;有效制冷量平均提高了6.02%;节省电能6.39%.圆孔翅片是3种片型中的最优片型.

Experimental Study on Refrigeration Performance of Fin-tube With Circular Hole Under the Frost Condition

The performance of heat transfer of fin-tube with circular hole is better than fin-tube without hole if there is no frost,but what is the situation if under the frost condition.Tthe comparison study on performance of heat transfer and refrigeration is carriedout under the frost condition for the heat exchanger with three kinds of fins: circular and half circular hole,circular hole,plane form.The experiment process is finished through the refrigeration system of icebox.In the course of experiment,the influence of frost process to the diameter of circular hole;is analyzed The real refrigeration amount,heat transfer coefficient and real refrigeration coefficient of the three kinds of fins are compared;compare the effect of energy saving of enforced fins is given.The fin efficiency is calculated method and make out the real convection coefficient to disclose the situation of heat transfer of fins is lnade out.Results: compared with plane form fin,the following results are for fin-tube with circular hole: average heat transfer coefficient rise 11.53%,convection coefficient rises 18.84%,real refrigeration coefficient rises 6.83%,virtual refrigeration amount rises 6.02%,electricity saving is 6.39%.Fin-tube with circular hole is the best form for the three kinds of fins.