季节性气候变化对填埋场温度分布影响的研究

Research on the Impact of Seasonal Climate Change on the Distribution of Temperature in Landfill

基于热传导理论,根据能量守恒原理与傅立叶定律,建立了填埋场内温度传输的数学模型,并利用有限单元法进行了数值求解。数值模拟结果显示:在夏季,随着深度的增加,温度逐渐降低;冬季则相反。这是由于垃圾土的热传导系数不高,比热较大,而且使得温度的分布在空间上产生了滞后。在填埋场表层及浅层区域,由于受到传热效应的作用,其温度值几乎与外界大气温度一致。所建立的数值模型可以仿真填埋场内温度在空间上的分布变化规律,不仅为填埋气体产量和环境评价的研究提供理论依据,而且可为填埋场的气体收集系统和相关设计提供技术支持。

Based on heat transfer theory, energy conservation principle and Fourier' s law, a mathematical model of temperature transmission in landfill was established. The finite element method was used for discretization of the governing equation. The results showed that the temperature decreased with the increase of landfill depth in summer time, which is quite opposite to that of the winter time. And this is due to the low thermal diffusivity and high specific heat of refuse, which caused the non - uniform spatial distribution of temperature. In the surface layer of landfill, the temperature is quite close to that of the atmosphere, because of the heat transfer effects between surface layer and atmosphere. The model can be utilized for investigating temperature distribution in landfill and offering theoretic support for the research on landfill gas and the designing of gas control system.