Talking about which thermal insulation effect is better between glass greenhouse and film greenhouse
In recent years, with the advancement of facility agriculture, China's greenhouse industry has developed rapidly and has led to a large number of agricultural workers getting rich. It is now common practice around the structure of greenhouses, then in modern conservatory buildings current, excluding greenhouses, greenhouse membranes, and is a common type of structure; these two rooms, the type of which insulation performance is better
Performance introduction of glass greenhouse and film greenhouse
The glass greenhouse is a modern greenhouse developed in the early days. It has a high optical transmission rate and is overall beautiful, but the cost is high. Suitable for areas with poor lighting or good economic conditions. Glass is a rigid, light-transmitting material. Therefore, the usual glasshouses are spires. According to the structure, glass greenhouses are generally divided into three types: door steel frame structure greenhouse, truss roof structure greenhouse and Wenluo structure greenhouse. The main features of the Venlo-type greenhouse are small cross-section of components, simple equipment, long service life and easy maintenance. The relevant parameters are:
Structural span: 8m, 9.6m, 12m, 24m, etc.
Greenhouse eaves height: 4.00m, 5.00m, 6.00m, 8m, 10m and so on.
The multi-span greenhouse is an economical greenhouse, which is very popular among users because of its beautiful curved shape and low cost. The curved roof is beautiful and generous, and the line of sight is smooth. The structure is made of small steel, with good thermal insulation performance. The manufacturing cost is relatively low, and it belongs to the economic greenhouse, which is suitable for most parts of our country. In the north, double-layer greenhouses are mostly used, and single-layer greenhouses are mostly used in the south. It can illuminate in the visible light range of 0.4-0.7 microns. When the film is inflated, thick air pockets can be formed, effectively preventing heat loss and cold air intrusion. The use of double-layer inflatable film can greatly improve the thermal insulation performance of the greenhouse and save operating costs. The top of the cover material is covered with polyethylene drop-shaped long-life film, the outer layer is UV resistant and the inner layer is dew resistant. The surrounding material can be covered with polyethylene drip-free longevity film or polycarbonate hollow board according to user needs.
Comparison of thermal insulation effect between glass and film greenhouse
As we all know, temperature is the basic condition to ensure the normal growth of crops, and the greenhouse is a kind of thermal insulation agricultural facility for the normal growth and rapid growth of crops. Insulation is an important job in greenhouse agricultural production, so it is necessary to choose suitable covering materials. Generally speaking, glass greenhouses are better than glass greenhouses. Glass greenhouses can play a decorative role in appearance. Compared with plastic greenhouses, glass greenhouses have relatively few problems such as aging and damage; in terms of performance, due to the complexity of the environment , the glass greenhouse can relatively resist various loads (wind load, snow load, etc.). From aesthetics, durability, wind resistance, rain resistance, sunlight resistance, thermal insulation effect and cost, aluminum alloy (or stainless steel) plus plexiglass, plus ordinary glass, low-cost bamboo pool and plastic film, can also be equipped with sunshade net and sprinkler irrigation Drip irrigation sprinkler system, etc. Plants generally need plenty of light and better glass. Of course, the one-time investment cost of plastic is low, but the maintenance cost in the later period is also high, and the plastic is easy to age.
Greenhouse insulation measures
1. sometimes the rain and snow and the temperature are lower than zero, the greenhouse vegetables are not easy to be frozen, but after the first transparent weather, the clear after the rain or snow is prone to freezing damage. Part of the reason is that it is especially large after the start of the frost, so such weather requires special attention, and it is recommended to increase the first clear coverage.
2. For vegetables such as lettuce in the greenhouse, a layer of insulation facilities is not safe, because they have their own temperature requirements, such as eggplant and fruits and vegetables below 15 degrees Celsius will not re-grow; leafy vegetables include lettuce, lettuce and others below 5 degrees Celsius The vegetables will stop growing, and the sub-zero temperatures may even freeze. Therefore, these vegetables can be heated according to their own facilities, such as adding small arches and adding mulch.
3. Do a good job of keeping high-lane crops warm. Now, there are more tall crops such as tomatoes and cucumbers in greenhouses. Tall hurdle crops cannot be covered with small arches or leaves, so it is advisable to prepare a double layer of film before cold air arrives.
4. Add boilers or heaters in greenhouses with poor thermal conditions to prevent the arrival of extreme cold and cloudy days, so that the temperature in the greenhouse drops sharply and protects the normal growth of vegetables.
