地热水在矿山深部岩体单一裂隙中的渗流规律分析

选取PKN模型进行岩体裂隙地热水对流换热量的研究,计算了地热水在裂隙内的对流换热量,通过将裂隙截面展开求解对流换热面积,根据牛顿冷却定律计算得出对流换热量;由裂隙张开度的变化量计算岩体裂隙的渗流量,结果表明,在三维应力一定的条件下,岩体裂隙内地热水的渗流量随裂隙倾角变化而变化。从矿山中选取典型岩样进行加工,使之成为200 mm×100 mm×200 mm的标准岩样。试验结果表明,在裂隙倾角α=0°的情况下,裂缝的渗流量随β增加逐渐减小,并且在随β增加到90°的过程中趋于稳定,表明岩体裂缝为水平裂缝时渗流量最小,维持在一个稳定值;在α=90°的情况下,裂缝的渗流量随β增加逐渐增大,在β增加到90°的过程中,裂缝慢慢变为垂直裂缝,渗流量的变化也趋于缓和,增加到一个稳定值。

Analysis of the flow regularity of the geothermal water seepage under the mining conditions of the singularity fracture of the deep rock mass

This paper takes it as its goal to pursue the 2-D convective transferring regularity of the geothermal water in the single fracture condition of the deep rock mass so as to identify and determine the geothermal water seepage in the fracture caused by the energy conversion through the heat convection and transmission.For the study purpose,we have chosen the PKN model to trace the convective heat transfer of the fractured geothermal water as well as to calculate the quantity of the convective heat transfer of the ground water in the said PKN model.Besides,we have also attempted to work out the convective heat transfer area by unwrapping the fracture section while calculating the quantity of the convective heat transfer according to the Newton Cooling Law.In addition,the seepage flow of rock mass fracture has also been accounted for by the change of the opening degree of the fracture.The results of our study have thus shown that,under the condition of the 3-D stress,the seepage flow of the geothermal water in the rock mass fracture has been found to change with the change of the fracture angle.What is more,the paper has also selected typical rock samples from the mine to be processed into the typical rock samples of 200 mm × 100 mm × 200 mm.What is more,we have prepared some pieces of the experimental equipment and facilities oriented to analyze the relevant experiments.The results of the above theoretical and experimental research show that:in the case of the fracture angleα =0°,the seepage flow of the fracture has been found decreasing with the increase ofβ,whereas the seepage flow tends to decrease gradually to a stable value with the increase of the value ofβ to 90°,thus,indicating that,when the fractures are horizontal,the seepage tends to be the smallest though remains at a stable value.On the other hand,in the case if the fracture angle a =90°,the seepage flow of the fracture would increase with the increase ofβ,so as for the fracture to turn slowly to be vertical with the seepage flow gradually increasing to a stable value with the increase ofβ to 90°.