The function of aluminum sunshade net:
(1) Shading, cooling and heat preservation. At present, the shading rate of shade nets produced in my country is 25% to 75%. Shade nets of different colors have different light transmittances. For example, the light transmittance of black shading nets is significantly lower than that of silver-gray shading nets. Because the shading net reduces the light intensity and the radiant heat of the light, it has an obvious cooling effect, and the higher the outside temperature, the more obvious the cooling effect. When the outside air temperature reaches 35-38°C, the general cooling rate can be reduced by up to 19.9°C. Covering the sunshade net in hot summer can generally reduce the surface temperature by 4 to 6 °C, and the maximum can reach 19.9 °C. After the sunshade net is covered, the solar radiation decreases, the ground temperature drops, the wind speed weakens, and the evaporation of soil moisture is reduced, which has obvious drought resistance. Moisture protection function.
(2) Wind-proof, rain-proof, disease-proof and insect-proof The shading net has high mechanical strength, which can slow down the loss of vegetables caused by typhoon, rainstorm, hail and other disastrous weather. The greenhouse is covered by a shading net. During a typhoon, the wind speed inside the shed is only about 40% of the wind speed outside the shed, and the wind blocking effect is obvious. The plastic greenhouse covered with the shading net can reduce the impact of the rainstorm on the ground to 1/50, and the rainfall in the shed can be reduced by 13.29% to 22.83%. The silver-gray sunshade net has obvious effect of avoiding aphids and can effectively reduce the spread and spread of viruses. Covering the net room with a shade net can prevent the damage of external pests and diseases. According to the test on autumn tomato, with silver-gray shade net covering, the incidence of plant virus disease is 3%, and 60% are not covered.
(3) Antifreeze and heat preservation In order to improve the utilization rate of the shade net and reduce the cost of covering, it can also be used for preventing early frost in late autumn, preventing late frost in early spring and preventing frost damage in winter. It has been determined that the silver-gray shade net can increase the surface temperature by 1.3 to 3.1 °C at night.