Based on the models of Campbell and de V-1, a new mathematic model for predicting soil thermal conductivity is developed in this paper. Using the parameters shape factors ( ga ) and soil solid thermal conductivity ( λm ) , the Campbell model is calculated by the method of the de V-1 model. According to this method, the soil solid thermal conductivity and shape factors are considered to be soil solid components, and include the effect of temperature on the soil solid thermal conductivity. By comparing the Campbell and de V-1 models, the measured results are in good accordance with the numerical ones, and the model shows better performance when predicting soil thermal conductivity. In addition, the effects of soil temperature and moisture on different soil thermal conductivities are studied. The results indi-cate that under the same soil temperature and moisture, the thermal conductivity of sand is greater than that of loam, and the thermal con-ductivity of loam is greater than that of clay. This will provide new ideas for establishing a coupled heat and moisture transfer model in un-saturated soil for heat exchangers.%本文在Campbell模型和de V-1模型的基础上,以Campbell模型为主,对该模型中的两个参数形状因子(ga)和土壤固相热导率(λm)采用de V-1模型中的计算方法,提出了一种新的预测土壤热导率温度关系的模型.该模型土壤固相热导率和形状因子均考虑了土壤颗粒组成成分,也包含了温度对土壤固相热导率的影响.此外,与前两种模型进行比较,该模型与实验值吻合较好,能够更好地预测土壤热导率.基于该模型,分析了土壤温度和体积含水率两个变量对不同类型土壤热导率的影响.研究表明:在同一温度及体积含水率工况下,土壤热导率是砂土>壤土>黏土.该研究为地埋管换热器周围非饱和土壤热湿耦合迁移模型的建立提供新的思路.
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