为了预测和评价密闭遮光型甲鱼温室的湿热环境，构建了甲鱼温室湿热环境的一维传热理论模型。采用欧拉数值计算方法求解甲鱼温室的传热方程组，编制了基于Matlab的计算机程序，根据屋顶材料的热传导系数、屋顶的红外辐射特性、温室的结构参数、温室热量输入与气象参数等条件，模拟甲鱼温室传热过程，该模型可以获得甲鱼温室任意时刻的屋顶内外表面温度、室内温湿度、养殖水体温度以及热流量等数据信息，可为甲鱼温室的湿热环境综合分析提供依据。通过建立相应试验方案对模型结果进行验证，实测结果表明，屋顶外表面、内表面模拟温度与实测温度平均误差为1.96和0.9℃，养殖水体与室内空气模拟温度与实测温度平均误差为0.32与1.3℃，室内相对湿度模拟与实测平均误差为3%。模型的理论计算值与试验测定值较为一致，表明甲鱼温室的一维传热理论模型具有较高的准确性。%It is very important to maintain an optimum inside environment during the different stages of aquatic animals growth for modeling thermal behavior of aquaculture greenhouse. A mechanistic model was developed to describe the thermal behavior of a shading turtle greenhouse system with polystyrene foamed plastic envelope. Energy balance equations have been written considering the effects of conduction, convection, radiation, evaporation and ventilation. Numerical computations have been performed for special days in the month of January 2012, under the climatic conditions of Hangzhou in Eastern China. The governing equations are numerically solved using Matlab 7.0 software to predict the inside and outside surface temperature of the envelope, room temperature, relative humidity, and water temperature. At the same time, on-site measurements were taken at a turtle-breeding facility in Hangzhou for comparisons with predictions. Results showed that the average absolute errors of air temperature, water temperature, and relative humidity were 1.3, 0.32℃ and 3%, respectively. The results also showed that the internal air temperature and water temperature could maintain a relatively stable state by using two sets of 2.7 kW ground-source heat pumps for the turtle greenhouse heating (about 540 m2), a suitable thermal environment for the turtles growth. Model simulations were used to investigate the effects of the greenhouse on the air and water temperature and to examine the heatfluxes. The results suggest that the daily mean temperature is 5.8℃, the solar radiation is 132 W/m2, the room temperature maintains 35℃, and the water temperature maintains 30℃ when the heat pump provides 40 W/m2in January near Eastern China-Hangzhou. An examination of the heatfluxes suggests that thermal radiation and underground heat conduction are major mechanisms of heat loss for the greenhouse covers and water. About 44.5% of heat loss was caused by underground heat exchange, about 43% by built envelopment heat exchange, and about 12.5% was by air leakage. Reducing these heatfluxes will help conserve and utilize energy. Moreover, the model was deemed to be a useful tool for exploring the performance of heating greenhouse systems under different scenarios, such as different cover materials, sizes and climates.
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