A Study on Nonlinear Heat Convection Analysis in Sediment Rocks Concerning to the Deep Underground Development

作为沉积软岩的特征之一，可以指出，材料的渗透性相对较高，这有时会引起一些问题，例如来自软岩体中的能量存储罐的热流。软岩的风化特征之一可能是周期性裂隙，当裂隙中含有气泡时，它将影响整个岩体中的热量和水分流动。首先，考虑球形包裹体的周期性结构，研究了岩体的导热系数，并在忽略水分运动的情况下，分析了含水量和含气量对平均导热系数的影响，采用高30cm、宽30cm、厚2.5cm的砂层进行了模型试验。在砂层底部放置热源，采用加热的方法测量了两种不同渗透系数模型的温度分布。然后用有限元法进行数值分析，研究了土体渗透性的影响。数值模型得到了很好的近似，这表明了显着的影响对流加热的孔隙水。用另一种模型模拟了岩体中的裂隙带，并研究了水流对岩体导热系数的影响。

As one of characteristics of sedimented soft rock it can be pointed out that the permeability of the materials are relatively high, and this sometimes gives rise to some problems such as in heat flows from the energy storage tanks in a soft rock mass. One of the features of weathering of soft rocks might be modeled by periodic cracks, which will affect heat and water flows in the rock mass as a whole when it contains the air bubbles in the fissures. Firstly, heat conducivity of rock mass was studied by considering periodic structure of sphere inclusion, and effects of water content and air content on the average heat conductivity were analytically studied when moisture movement was neglected.The model experiment was executed using a sand layr of 30cm in height, 30cm in width and 2.5cm in thickness. A heat source was placed at the bottom of the sand layr and the temperature distribution for two models with different permeability coefficient was measured in the way of heating. Then numerical analyzes were also made by finite element method, and effect of permeability of soils were studied. Good approximation was obtained by the numerical model, which shows a significant influence of convection by the heating of pore water. Another model was used to simulate the fracture zone in a rock mass and also effect of water flow on the heat conductivity was studied.