地下水源热泵地下水渗流场自适应网格法  

Adaptive mesh refinement technique for seepage flow field in groundwater source heat pump system

作　　者：王晓宏[1] 施安峰[1] 郑晓磊[1] 贾江涛[1] 

机构地区：[1]中国科学技术大学热科学和能源工程系,安徽合肥230027

出　　处：《排灌机械工程学报》2012年第6期621-626,共6页Journal of Drainage and Irrigation Machinery Engineering

基　　金：国家自然科学基金资助项目(11172295);中国科学院知识创新工程重大项目(KJCX1-YW-21)

摘　　要：快速高效的数值计算方法对于地下水源热泵采能技术的发展及应用具有重要的实际工程意义.地下含水层的边界通常较为复杂,和非结构化网格相比,采用结构化网格计算方法可以有效减小数学方程离散的复杂度,并有利于发展地下水源热泵系统地下水渗流场自适应网格计算方法.为发展结构化网格计算方法,对位于含水层边界处的网格提出了一个在数学上简单有效的预处理方法,在计算过程中采用界面渗透率取代网格自身渗透率参与实际计算,并对含水层边界处网格的界面渗透率给出相应的计算方法.三维验证算例显示,对于非规则边界,即使采用网格尺度较大的正交规则网格,计算解也十分接近收敛解.提出仅对温度梯度变化较大的区域采用较小尺度的精细网格计算,而温度变化较缓的区域则采用不同层次的粗网格计算,利用自适应网格法计算地下水源热泵地下水渗流场,在保持计算精度的同时,计算速度得到了大幅度提高.A fast and highly efficient numerical computational method has important practical significance for development and application of the technology in groundwater source heat pumps.Normally the boundary of an aquifer has an irregular-shape.Compared with unstructured grids,adopting structured grids can effectively decrease the complexity in discretization of the mathematical equations and is very beneficial for developing an adaptive mesh refinement（AMR） algorithm to simulate the seepage flow field of groundwater source heat pump system.To develop a computational method based on the structured grids,a simple pretreatment method was proposed to deal with the grid cells on the aquifer boundary.In the method,the effective permeability on the interfaces between grid cells rather than those of the grid cells was involved in computations,further an algorithm for calculating the effective permeability on the six faces of a grid cell was proposed.The three-dimensional computational examples show that even more coarse cells are adopted a more accurate result can be reached for a domain with irregular boundary.In the AMR algorithm the cell sizes depend on the temperature gradient,i.e.the smaller cell size the lower the gradient;as a result of this,the time consuming for simulating the underground seepage flow in a groundwater source heat pump system is reduced considerably but the accuracy remains the same.

关 键 词：地下水源热泵 渗流 自适应网格法 等效渗透率 

分 类 号：S277.9[农业科学—农业水土工程] TK523[农业科学—农业工程]