Evaluation Insulation Effect And Performance Of Four Kinds Of Solar Greenhouse Insulation Covering

To study heat loss at night in Greenhouse roof, increase (November2015-February2016) measures greenhouse insulation effect of winter, the experiment use four solar greenhouse insulation cover (two internal thermal screen, two outer covering insulation) as materials, test material thermal conductivity and water resistance in laboratory, then observant greenhouse environmental changes which covered with four kinds of insulation material, and analysis Insulation’s affect to greenhouse tomato, the following results:1.Outer covering insulation’s effect and performance(1)low temperature in winter and precipitation conditions, waterproof insulation was the best performance of waterproof, foam composite insulation was the best performing insulation properties, and needle felt insulation was the worst performer.(2)two kinds of insulation was increased greenhouse’s saving rate. Waterproof insulation and foam composite insulation’s hot greenhouse savings rates were higher than the control greenhouse needle felt insulation was 2%和6%.(3)①two kinds of insulation were increased greenhouse nighttime temperatures, and foam com posite insulation performance is optimal. Waterproof thermal insulation warming effect is sunn y> cloudy> snow, average temperature, minimum temperature, respectively, compared with the c ontrol greenhouse increase 1℃,0.5℃; foam composite insulation warming effect in snow day i s outstanding, higher 2.3 ℃ compared with the control, the average greenhouse temperature, min imum temperature, respectively, compared with the control greenhouse increase 2.5 ℃,1℃; two kinds of geothermal greenhouse insulation was improved in the range of 0.5-0.8℃. ②two kinds of insulation can reduce greenhouse’s relative humidity about 5%; in cloudy sunny day, water proof thermal insulation is reduced by 5% in greenhouse relative humidity, waterproof insulatio n and the control insulation do not have obvious difference, ③two kinds of greenhouse insulati on was exothermic night were higher than the control greenhouse. Waterproof insulation and fo am composite insulation greenhouse was wall and floor heat at night total respectively than the control greenhouse 5.07W/m2,5.78W/m2.(4)in two insulation’s greenhouse tomato was morphological indexes and yield better than the control greenhouse. ①two kinds of insulation was greenhouse tomato plant height, stem diameter greater than the control, and the composite foam insulation is a greenhouse tomato plant height, leaf length and waterproof insulation was in control there are significant differences, ②two kinds of insulation was greenhouse tomato production increase, foam composite insulation greenhouse was tomato harvest earlier week yield 114kg/667m2 compared with the control tomato greenhouse.2. Internal thermal screen’s effect and performance(1)using the outer cover additional insulation measures within the insulation cover greenhouse can significantly improve the greenhouse insulation effect. From the thermal point of view, while the use of needle felt insulation was with tension felt Thermal Screens greenhouse insulation performance is better than at the same time using the needle felt insulation and insulation screen transparent PE film greenhouses and insulation resistance are superior than only use needle felt insulation in greenhouse.(2)in the case of needle felt insulation and provided additional thermal screen can increase greenhouse energy saving rate. Each additional tension felt Thermal Screens, transparent PE film thermal screen in greenhouse saving rate of 5%,6%,11%,7%.(3)①two kinds of thermal screen can improve the greenhouse temperature at night, warming effect snow> cloudy> sunny. In snow day, tension felt Thermal Screens and PE film were compared with the control, greenhouse temperature increase 2.8 ℃,4.3 ℃; the average temperature of the tension felt Thermal Screens, PE film thermal screen in greenhouse were higher than the control greenhouse 2℃, 3.5℃; minimum temperature increased 0.5℃,1.0℃; greenhouse ground temperature increased 0.4℃ and 0.8 ℃. ②under different weather conditions,additional tension felt Thermal Screens can reduce greenhouse relative humidity of 3%-5%, additional PE insulation curtain increase greenhouse relative humidity 3%-6%, cloudy day significant difference,③adding two kinds of insulation, the greenhouse’s heat insulation at night were higher than the control greenhouse. Additional PE film and tension felt Thermal Screens Thermal Screens greenhouse wall and floor were higher than the control nighttime heat release of 2.8W/m2,4.39W/m2.3. Comprehensive Performance Evaluation(1)under the comprehensive evaluation function tested four kinds of insulation, insulation covering comprehensive evaluation ranking is:Rally felt needle felt insulation+thermal screen>composite insulation>needle felt insulation+black PE film> needle felt insulation.Described that needle felt insulation Screens+thermal screen were in greenhouse in winter improving insulation performance test, have the best overall performance.