CAJ | 학술논문

核废物地质处置、地热开发、石油开采等工程领域都可能涉及稀疏裂隙岩体中的水流-传热过程。现有的裂隙岩体水流-传热理论模型和计算方法基本上都是以平行光滑壁面裂隙模型为基础的，没有考虑裂隙的壁面局部接触对水流、水-岩热交换以及岩体传热的影响。针对粗糙壁面裂隙水流过程，阐述了基于Stokes方程的Reynolds润滑方程及Hele-Shaw裂隙模型，采用MATLAB软件中的PDE工具求解，并与Walsh的等效水力开度公式进行对比；分析壁面局部接触裂隙水流-传热与填充裂隙水流-传热的相似性，提出了瞬时局部热平衡假设的适用条件，并在裂隙局部接触体传热满足Biot数条件的前提下，计算分析裂隙局部接触体与水流之间的局部热平衡时间及其影响因素；在裂隙局部接触体与水流之间满足瞬时热平衡假设的前提下，利用填充裂隙水流-传热的解析解，计算了壁面局部接触裂隙水及两侧岩石的温度分布，并分析了裂隙局部接触面积率、裂隙开度、裂隙水平均流速对岩石温度和裂隙水温度的影响特征，结果表明：（1）在设定条件下，由于裂隙局部接触体与裂隙水流之间的热交换，裂隙水流对其两侧岩石温度的影响范围随接触面积率的增大而减小，裂隙两侧岩石对裂隙水流温度的影响程度随接触面积率的增大而增大；（2）裂隙开度和裂隙水流速对岩石温度和裂隙水温度的影响方式的影响是一致的，即由于裂隙水流量随裂隙开度和裂隙水流速的增大而增大，裂隙水流对其两侧岩石温度的影响范围随裂隙开度和裂隙水流速的增大而增大，裂隙两侧岩石对裂隙水流温度的影响程度随裂隙开度和裂隙水流速的增大而减小。
핵폐물지질처치、지열개발、석유개채등공정영역도가능섭급희소렬극암체중적수류-전열과정。현유적렬극암체수류-전열이론모형화계산방법기본상도시이평행광활벽면렬극모형위기출적，몰유고필렬극적벽면국부접촉대수류、수-암열교환이급암체전열적영향。침대조조벽면렬극수류과정，천술료기우Stokes방정적Reynolds윤활방정급Hele-Shaw렬극모형，채용MATLAB연건중적PDE공구구해，병여Walsh적등효수력개도공식진행대비；분석벽면국부접촉렬극수류-전열여전충렬극수류-전열적상사성，제출료순시국부열평형가설적괄용조건，병재렬극국부접촉체전열만족Biot수조건적전제하，계산분석렬극국부접촉체여수류지간적국부열평형시간급기영향인소；재렬극국부접촉체여수류지간만족순시열평형가설적전제하，이용전충렬극수류-전열적해석해，계산료벽면국부접촉렬극수급량측암석적온도분포，병분석료렬극국부접촉면적솔、렬극개도、렬극수평균류속대암석온도화렬극수온도적영향특정，결과표명：（1）재설정조건하，유우렬극국부접촉체여렬극수류지간적열교환，렬극수류대기량측암석온도적영향범위수접촉면적솔적증대이감소，렬극량측암석대렬극수류온도적영향정도수접촉면적솔적증대이증대；（2）렬극개도화렬극수류속대암석온도화렬극수온도적영향방식적영향시일치적，즉유우렬극수류량수렬극개도화렬극수류속적증대이증대，렬극수류대기량측암석온도적영향범위수렬극개도화렬극수류속적증대이증대，렬극량측암석대렬극수류온도적영향정도수렬극개도화렬극수류속적증대이감소。
Water flow and heat transfer processes in fractured rocks may be encountered in several engineering disciplines, such as geological disposal of radioactive waste, geothermal development, petroleum exploration, etc. Currently existent theoretical models and calculation methods for water flow and heat transfer in fractured rocks are almost exclusively based on the assumption of parallel smooth fracture walls, without considering the effects of local fracture wall asperity contacts on water flow, water-rock heat exchange and heat transfer. The following studies are presented in this paper. Firstly, dealing with water flow in a fracture with rough walls, the Reynolds lubrication equation and the Hele-Shaw model of a fracture with local wall asperity contacts based on the Stokes equations are expounded;solutions are sought by using the PDE tool of the MATLAB software, and compared with the Walsh formula of the effective hydraulic aperture of a rough walled fracture. Secondly, the similarity between the water flow and heat transfer in a fractured rock with local fracture wall asperity contacts and the water flow and heat transfer in a fractured rock with fills is analyzed; the condition for applicability of the instantaneous local thermal equilibrium is proposed;and the time and its influencing parameters for local thermal equilibrium between the local fracture wall asperity contacts and the flowing water in the fracture are computationally analyzed under the premise that the Biot number condition can be satisfied by the local fracture wall asperity contacts. Lastly, assuming instantaneous local thermal equilibrium between the local fracture wall asperity contacts and the flowing water in the fracture, the distributions of temperatures in the flowing water and the rock matrix are calculated using an existing analytical solution for water flow and heat transfer in a fractured rock with fills, and the effects of the ratio of local asperity contact area, the fracture aperture and the averaged water velocity on the temperature distributions are analyzed, which indicate, under the prescribed conditions, (1) that due to the heat exchange between the local fracture wall asperity contacts and the flowing water in the fracture, the range of influence of the flowing water on the temperature of the rock matrix decreases with the increase of the ratio of local asperity contact area, whereas the degree of influence of the rock matrix on the temperature of the flowing water in the fracture increases as the ratio of local asperity contact area increases;(2) the influences of the fracture aperture and the water velocity on the temperatures of the rock matrix and the flowing water in the fracture are consistent in that the range of influence of the flowing water on the temperature of the rock matrix increases with the increases of the fracture aperture and the water velocity, whereas the degree of influence of the rock matrix on the temperature of the flowing water decreases as the fracture aperture and the water velocity increase.