The conclusion showed that pad-fans system was more effective for the cooling of closed piggery in low humidity area,and high pressure spray system was more effective for the cooling of open piggery and semi-enclosed piggery in high humidity area.

Through the actual test of the large-scale greenhouse with pad and fan cooling system which located in the high temperature and humid coastal district, the temperature condition in the two kinds of greenhouses were observed.

Wet curtain Pre-cooling technology is a new type of air-conditioning energy saving technology,Not increasing the area of condenser and evaporator,under the premise of a substantial increase in the efficiency of refrigeration units.

The wet curtain refrigeration technology is one kind of new air temperature decrease technology, whose characteristic is that the refrigeration quantity is large, the power consumption is low, the operation is reliable, the installment is convenient, and the service life is long.

The mass transfer coefficient and drop of pressure in wet curtain are meassured bymeans of counterflowing.

To improve evaporative pad s heat and mass transfer efficiency, decades correlative study methods on both experimentation and simulation are summarized, more deeply mainly mechanism in the body of evaporative pad is analyzed,and new ideal of study of evaporative pad using some modern methods are suggested.

Is this paper the research had separately carried out in the experimental barns(including farro- wing barn and weaning barn)which were heated by heated air furnace and cooled by evaporative pad and fan sys- tem,and in the contrast barns which were heated by stove and cooled by natural ventilation.