| Solar greenhouse is one of the main facilities for agricultural production of vegetable cultivation in the northern region by using solar radiation as a source of energy.However,under continuous bad weather conditions,the benefit of solar greenhouse has been gradually limited.For the heat preservation performance of solar greenhouse in northern China,heat storage and heat release characteristics of water used in this experiment to improve the utilization rate of solar greenhouse vegetable production to meet the anti season cultivation of thermal environmental conditions for equilibrium of supply in North China Anti season fresh vegetables made great contribution.In this study,the inner thermal insulation greenhouse was studied in Baotou Academy of Agriculture and Animal Husbandry and Sciences,and 28 water pipes with diameter of 0.1 m,height of 3m and spacing of 0.4 m were installed in the back wall(37 walls)of solar greenhouse.The total volume of 0.66 m3,the total length of the test area and control area are 14m.The solar energy storage system can enhance solar thermal efficiency and improve the thermal environment of solar greenhouse purposes,and reduced the construction of solar greenhouse wall costs.However,there are few literatures on the practical application of water storage in solar greenhouse.Therefore,this study studies the environmental conditions after adding thermal storage pipes to provide theoretical guidance for the design and practical application of heat storage water pipes in the future.In this experiment,the effect of heating water storage pipe on the thermal environment of solar greenhouse was studied with 37 wall solar greenhouse as a contrast.The results show that:1.The installed capacity of the installed heat storage unit was 73.8 MJ/m~3;After installing the heat storage water pipe,the heat storage capacity of the rear wall of the solar water storage tank increased by 69.6 MJ/m~3.2.Compared with the control greenhouse,Installing heat storage water pipes,the day and night temperature difference of the rear wall is 0 cm,10 cm and 20 cm away from the inner surface decrease respectively 3.8??1.9??1?;The sunny day,in the test area and control area,the lowest temperature difference of rear wall that 0 and 20centimeters from the wall surface were 0.8?and 2.5?,continuous(3days)under adverse weather conditions,the lowest temperature difference of rear wall that 0 and 20centimeters from the wall surface was 0.8?and 1.6?.3.Installing heat storage water pipes in solar greenhouse,the average daily minimum air temperature was increased by 0.7?~2.4?;Compared with the control area,on a sunny day,the lowest temperature of the test area in the greenhouse increase 2.3?;When it is cloudy,the lowest temperature of the test area in the greenhouse increase0.8?;In January,in the test area,the average maximum temperature,average minimum temperature and average temperature than in the control area were increase 5.2??0.7?and 1.4?.4.Under the continuous(3days)under adverse weather conditions,the daily minimum temperature of solar greenhouse soil temperature increased by 2.6?~3.1?,and under the condition of continuous sunny days(3 days)the daily minimum temperature of solar greenhouse soil temperature increased by 2?~3.7?;The average daily soil temperature was increased by 0.2?~2?,The average soil temperature at night was increased 0.4?~2.3?.In summary,installing heat storage water pipes in solar greenhouse,the environmental indexes such as thermal insulation,air temperature and soil temperature of the greenhouse wall have been improved compared with the ordinary 37 wall solar greenhouse,which is suitable for popularization and application in the actual production. |
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