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Energy through the solar solar greenhouse. Daytime solar radiation to the greenhouse, the indoor temperature rises, can reach more than 35 ℃ maximum temperature in the sunny, partly in the form of heat stored in the back wall of the gable and soil; night, when the indoor temperature drops, the wall and the soil heat accumulation in a steady stream to supply to the greenhouse. Due to the limited capacity of solar greenhouse heat storage and insulation, the rest of the night temperature is often relatively low, it is difficult to meet the demand for crop growth. To solve this problem, this paper proposes the use of the idea of ??\Clear test greenhouse solar heat, with water as a heat storage medium, greenhouse shallow soil regenerator during the day by the water loop heat is collected and stored in a greenhouse in the shallow soil, night soil's natural exothermic the heat is released into the greenhouse, greenhouse nighttime temperatures. The results showed that: this regenerative method increases the heat storage capacity of the greenhouse trials the greenhouse with control greenhouse temperature difference, was later covered with insulation, began to increase, and the average temperature difference of 4.0 ° C. Test greenhouse soil 60cm or more regional temperature has been higher than the control greenhouse 0cm at night mean temperature difference of 3 ° C, 30cm at nighttime average temperature difference of 3 ° C, the the 60cm at nighttime average temperature difference of 5 ° C. Overcast greenhouse solar radiation small and the smaller the heat accumulated during the day, the greenhouse heating may be achieved by two processes, the first part of the night through natural heat release heated greenhouse; when the greenhouse temperature is lower, and then start the heat pump system is heated, ensure that the entire ambient temperature at night. Open heat pump heating, due to the heat in the shallow soil is enhanced by the heat pump transfers the greenhouse back wall of the heat pipe, and then through the back wall of the heat to heat the greenhouse, heat flows from north to south, often causing greenhouse north and south The uneven temperature distribution. General greenhouse minimum temperature opened insulation was before, so this point in time to be taken into account in the setting of the heating period, 2:00 to 7:00 on a cloudy day. Simulation and measured values ??of the cross in the air temperature trends by model simulation test greenhouse analog value and the actual value of the absolute error is ± 1.3 ° C, average relative error of 8.2% IA = 0.65; the test greenhouse soil at 10cm analog trend of changes in temperature and measured values, the absolute error of the analog value and the measured value ± 0.4 ℃, the relative error of 1.1%, IA value of 0.73; 30cm soil Found and analog values ??close to the analog value is slightly higher than the measured value curves. better analog value and the measured value of the absolute error of ± 0.1 ° C, the relative error of 0.3%, IA value of 0.99; 50cm soil depth analog value is higher than the measured value, but the analog value and the measured value changes the same trend, analog value and the measured value of the absolute error is ± 1 ℃, the relative error of 4%, IA = 0.76. Validated model to analyze the impact of different buried depth of the the crop root layer (30cm depth) temperature, although the pipe can increase the soil temperature at 30cm depth increases, but increased after 36cm increase Buried The depth will increase the cost of labor, therefore, the best greenhouse Buried Depth 36cm, so not only guarantee a 30cm soil temperature is less affected by the impact of the fall in temperature within the heat exchange tubes and reduce unnecessary labor costs.
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