| The heat preservation of thermal insulation covering materials is a key factor that determines the solar greenhouse thermal insulation properties. However, there isn’t a standard for producing and using the insulation covering materials, existing blindness use. It is badly need of developing a quantitative criteria for thermal insulation covering materials using. For this reason, in this study the grass carpet is used for contrast. The heat flux of polystyrene foam (hereinafter referred to as polystyrene board, cotton blanket, pearl wool, foam polyurethane and a kind of compound heat preservation quilt is measured by hotbox method. After calculating, Excel handling and DPS data analyzing, the relationship of thermal resistance, thickness, temperature difference and moisture content is obtained. The results of the research are as follows: Under the condition of single variable:In the test of materials thermal resistance influenced by thickness, it is a result that the relationship between thermal resistance and thickness of all these materials have a linear relation, the relational expressions respectively are:y= 0.4356x+1.3982,R2= 0.9971;y= 0.0821x+0.3149,R2= 0.9676;y= 0.176x+0.2058,R2= 0.9865;y= 0.0609x+0.7957,R2= 0.9434;y= 0.0915x+0.8363,R2= 0.9728.In the test of materials thermal resistance influenced by temperature difference, it is a result that the relationship between thermal resistance and temperature difference is not the same. The thermal resistance and temperature difference between polystyrene board and the compound heat preservation quilt have a quadratic correlation, the relational expressions respectively are: y=-0.0173x2+0.2369x+2.2949,R2= 0.901;y= 0.0915x+0.8363,R2= 0.9948. Cotton blanket, pearl cotton, and foamed polyurethane thermal resistance and temperature difference show exponential, logarithmic, linear correlation respectively, relational expressions are:y= 0.8363x-0.053, R2= 0.8001; y=-0.061ln(x)+0.9513, R2= 0.8706; y=-0.0358x+ 1.3021,R2= 0.9067.In the test of materials thermal resistance influenced by different moisture content, it is a result that the relationship between thermal resistance and moisture content of polyurethane and cotton blanket have a linear correlation, the comparison expressions respectively are:y=-0.0551x+3.2153,R2= 0.991; y=-0.0031x+0.7768,R2= 0.986. And the relationship between thermal resistance and temperature difference of cotton blanket, pearl cotton and polyurethane have a exponential correlation, relational expressions respectively are:y= 0.7947e-0.015x,R2= 0.9174; y= 1.0557e-0.012x,R2= 0.9735; y= 0.902e-0.011x,R2= 0.9632.Under the condition of multivariate (thickness, temperature difference and the moisture content change at the same time):The relationship between polystyrene, cotton blanket, pearl cotton, foam polyurethane thermal resistance, thickness, the temperature difference and moisture content are: y=0.584+0.125d+0.005△T-0.032fw,R2=0.886;y=0.481+0.103d-0.007△T-0.001fw, R2=0.963;y=0.3984+0.15-0.006AT-0.001fw, R2=0.963;y=0.898+0.163d-0.010T-0.008fw, R2=0.931; The relational expression of thermal resistance, temperature difference and moisture content of heat preservation quilt of 2000g·m-2 are:y=1.047-0.004△T-0.004 fw, R2=0.902;The relational expression of thermal resistance, temperature difference and moisture content of heat preservation quilt of 2250g·m-2 are:y=1.058-0.003△T-0.005 fw,R2=0.955;The relational expression of thermal resistance, temperature difference and moisture content of heat preservation quilt of 2500g·m-2 are:y=1.313-0.010△T-0.004 fw, R2=0.961. |
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