| With the rapid economic development, China's energy and environment are worsening. Rational development and utilization of renewable energy, improve the energy efficiency is an important issue. Phase change energy storage technology is a very active research frontier, which has far-reaching significance on improving the energy structure, reducing pollution, promoting economic development and easing the pressure on China's energy problems. China, especially in northwest of China, has rich light and heat resources. Greenhouse is energy-efficient buildings which is full use of solar energy. Development of new greenhouse heat storage technology to greater use clean renewable solar energy is a key issue in the greenhouse industry.This thesis used phase change materials combined with materials to make new thermal insulation greenhouse wall materials. Use phase change energy storage technology to reduce greenhouse energy consumption and improve the greenhouse thermal environment. In order to solute the leakage problem, this thesis used a polyethylene plastic film whose thickness is 0.08~0.12mm to encapsulate phase change materials. The best mix of phase-change hull block is determined by orthogonal test. After measurement, the apparent density is 1200kg/m3, the compressive strength is 5.5MPa and the thermal conductivity is 0.811W/(m·K), which can meet the requirements of load-bearing and thermal insulation of greenhouse wall materials.This thesis measured the insulation performance of four types of new phase change wall greenhouses by contrast test. The result shows that new phase change wall can effectively reduce greenhouse energy consumption and improve the greenhouse thermal environment. Compared with the common greenhouse, the average minimum temperature at night of phase-change block greenhouse A is 1.9℃higher, the average night temperature is 1.3℃higher on average, the average maximum temperature during the day is 6.2℃lower, the average indoor temperature fluctuation throughout the day is 7.9℃less, the average inside and outside wall surface temperature fluctuation is 5.0℃less; the average minimum temperature at night of phase change wallboard greenhouse is 0.4℃higher, the average night temperature is 0.6℃higher on average, the average maximum temperature during the day is 3.2℃lower, the average indoor temperature fluctuation throughout the day is 3.5℃less; when the maximum indoor temperature is less than 30℃, indoor minimum temperature of phase-change block greenhouse D is 1.1℃higher, the average night temperature is 1.1℃higher on average, the average maximum temperature during the day is 3.4℃higher, the average temperature during the day is 1.6℃higher on average, the average inside and outside wall surface temperature fluctuation is 1.2℃less; when the maximum indoor temperature is higher than 30℃, indoor minimum temperature of phase-change block greenhouse D is 0.9℃higher, the biggest is 2.0℃, the average maximum temperature during the day is 3.7℃lower, the biggest is 5.3℃, the average indoor temperature fluctuation throughout the day is 4.6℃less, the average inside and outside wall surface temperature fluctuation is 1.6℃less; indoor minimum temperature of phase-change hull block greenhouse is 1.4℃higher, the average night temperature is 0.8℃higher on average, the average maximum temperature during the day is 2.2℃lower, the biggest is 4.2℃, the average indoor temperature fluctuation throughout the day is 3.3℃less, the biggest is 6.0℃, the average inside and outside wall surface temperature fluctuation is 2.5℃less, the biggest is 5.2℃.Based on the analysis of the data, this paper proposes a new idea. When we choose PCM which applied in the internal wall of greenhouse, we should consider the difference between indoor and internal wall temperature. The phase transition temperature range should be slightly lower than temperature which is suitable for crop growth. So PCM can also play a role when indoor temperature is suitable for crop growth.
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