Research On The Properties Of Agricultural Heat Preservation Quilt For Greenhouse

The temperature in the north at night in winter is relatively low.In order to maintain a certain temperature in the greenhouse to ensure the normal physiological activities of the crops indoors,heat loss of the enclosure must be reduced as much as possible.Covering the front roof of the greenhouse with a heat preservation quilt overnight is an effective method to improve the thermal resistance.Agricultural insulation materials turns new every few years,and their thermal insulation property are of varying quality.The insulation materials involved in the earlier studies are quite different from the insulation materials on the market.Moreover,the research on the properties of agricultural insulation materials has also decreased in recent years,and ordinary users know little about their properties.Therefore,test and study on the properties of heat preservation quilt,evaluation of the common composition of the structure of heat preservation quilt and surface materials on the market and screening materials and the composition of the structure of heat preservation quilt meet the requirements of the manufacturing,reasonable selection and use of heat preservation quilt.And it is of practical significance for the development of facility agriculture.This study collected 27 kinds of heat preservation quilts that are currently on the market.A static hot box was used to test the thermal insulation property of 17 waterproof quilts and 9 quilts with strong non-woven fabrics(not waterproof),comparing with a kind of quilt(oxford cloth + plastic film + recycled felt + strong non-woven fabrics)that is commonly used in Yangling.The waterproof of the 17 waterproof quilts is tested by weighing method;the mechanical strength of the 11 surface materials is tested by the strength tester,and the 6 of the 11 surface materials were tested by the UV artificial aging tester.The main results are listed as following:(1)The best 3 kinds of heat preservation core material is glueless cotton,space cotton and compound EPE.(2)The mechanical strength of the black PE woven fabric(the warp mechanical strength:15.33 N/mm)as surface covering material is significantly higher than that of other surface materials,and the black PE woven fabric has good resistance to aging(the reduction in mechanical strength after aging is the smallest,only by 5.20%).Therefore,the black PE woven fabric is a kind of ideal surface material for heat preservation quilt.(3)The combination of multiple materials is better than a single material.EPE shows poor thermal insulation property as heat preservation core material alone,but better with other materials togther.The combination of “EPE+space cotton+EPE”performs well,because it exerts the advantages of both materials.(4)Sponge performs well in waterproof,but it is not suitable for heat preservation core material because of its poor thermal insulation property,high price(25 ? / ?)and inconvenience.(5)The cost analysis shows that the glueless cotton(8.40?/500g)and space cotton(10.42?/500g)is the best as heat preservation core material,and the black PE woven fabric(1.55?/?)is the best as surface material because of its low price,high mechanical strength and good aging resistance.