下挖式日光温室土墙温度和热流的变化规律

2011年12月-2012年3月,在山东寿光对下挖式日光温室土质后墙不同厚度层的温度、热流进行连续测试,分析了下挖式日光温室土墙温度和热流的变化规律,确定了土墙的合理厚度.结果表明: 冬季,研究区温室墙体内侧表面、外侧覆盖层表面温度、热流的变化幅度较大,且与室内外气温的变化趋势相同.墙体温度总体上由内侧表面到外侧表面呈不断降低的趋势,墙体内侧温度、热流变化幅度较大的层次多于外侧.墙体温度、热流的变化幅度从浅层到深层依次减小.连阴天条件下,墙体内侧各层温度都有不同程度的下降,向室内放热的层次不断加深,而外侧各层次以向室外放热为主.根据墙体温度和热流的变化规律,在墙体外侧有覆盖层的情况下，把墙体从内到外划分为蓄热层、过渡层和御冷层,其厚度分别为0.8～1.0 m、2.2～2.6 m和0.4～0.6 m.在不考虑过渡层的条件下,寿光日光温室土墙厚度以1.4～1.6 m为宜.

Variation patterns of soil wall temperature and heat flux in sunken solar greenhouse

From December 2011 to March 2012, a consecutive test was conducted on the temperature and heat flux of different thickness of the soil backwall of sunken solar greenhouse in Shouguang of Shandong Province, East China, aimed to analyze the variation patterns of soil wall temperature and heat flux of the sunken solar greenhouse and to confirm the suitable wall thickness. In winter, the temperature and heat flux of the wall inner surface and outer surface varied over a wide range, which was in accordance with the variation trend of indoor and outdoor air temperature. Overall, the wall temperature decreased from the inner to the outer surface, and the layers of the inner wall with higher variation range of temperature and heat flux were more than those of the outer wall. The variation range of temperature and heat flux decreased gradually from the shallow layers to deep layers of the wall. In successive cloudy days, the temperature of each layer of inner wall decreased to different degrees, and the layers releasing heat to the indoor deepened constantly, whereas the heat in the layers of outer wall was mainly released to the outdoor. According to the variation patterns of temperature and heat flux in the wall, the wall from inside to outside could be divided into heat storage layer, transitional layer, and cold resistant layer, and their thickness was 0.8-1.0 m, 2.2-2.6 m, and 0.4-0.6 m, respectively, under the condition of the outer surface being covered. Without considering the transitional layer, the suitable thickness of the soil wall in Shouguang solar greenhouse would be 1.4-1.6 m.