Chinese solar greenhouses enable the extension of the crop growing season in the cold climate in Northern China with little or no additional heating.The temporal variations of the air temperatures inside solar greenho...Chinese solar greenhouses enable the extension of the crop growing season in the cold climate in Northern China with little or no additional heating.The temporal variations of the air temperatures inside solar greenhouses located at three cities in North,Northeast and Northwest China were predicted by CFD simulations of the greenhouse systems using typical meteorological data.The predicted temperatures based on the meteorological data in Shenyang are quite similar to the measured temperatures.The results also show that the external air temperatures and solar radiation fluxes play more important roles for the inside temperatures as indicated by the highest inner temperature in the morning on Feb.18 and from 10:00 to 14:00 on Feb.19 in Beijing and by the predicted temperatures inside the greenhouse being higher in Lanzhou than those in Shenyang and Beijing during most of the day.The average daily temperature inside the greenhouse in Lanzhou was nearly 3.5℃higher than that in Shenyang.Predicted air temperatures for various wall designs show that for single walls,the daily average interior temperatures in the aerated concrete wall greenhouse were higher than those in the brick wall and reinforced concrete wall greenhouses.However,the air temperature fluctuations were lower in the reinforced concrete wall greenhouse due to greater thermal storage capacity.The results also show that the temperatures in the layered wall greenhouses are quite similar,which coincides with the experimental results。展开更多
基金the Ph.D.Programs Foundation of Liaoning Province,China(Grant No.20061040).
文摘Chinese solar greenhouses enable the extension of the crop growing season in the cold climate in Northern China with little or no additional heating.The temporal variations of the air temperatures inside solar greenhouses located at three cities in North,Northeast and Northwest China were predicted by CFD simulations of the greenhouse systems using typical meteorological data.The predicted temperatures based on the meteorological data in Shenyang are quite similar to the measured temperatures.The results also show that the external air temperatures and solar radiation fluxes play more important roles for the inside temperatures as indicated by the highest inner temperature in the morning on Feb.18 and from 10:00 to 14:00 on Feb.19 in Beijing and by the predicted temperatures inside the greenhouse being higher in Lanzhou than those in Shenyang and Beijing during most of the day.The average daily temperature inside the greenhouse in Lanzhou was nearly 3.5℃higher than that in Shenyang.Predicted air temperatures for various wall designs show that for single walls,the daily average interior temperatures in the aerated concrete wall greenhouse were higher than those in the brick wall and reinforced concrete wall greenhouses.However,the air temperature fluctuations were lower in the reinforced concrete wall greenhouse due to greater thermal storage capacity.The results also show that the temperatures in the layered wall greenhouses are quite similar,which coincides with the experimental results。