模擬岩石破裂面異向流場之觀測與分析

The Observation and Analysis of the Anisotropic Flow in Synthetic Rock Fracture

白英鈴(I.L. Bai) ； 王建力(C.L. Wang)

《鑛冶：中國鑛冶工程學會會刊》 48卷1期 (2004/03) Pp. 125-135

https://doi.org/10.30069/MM.200403_48(1).0009

摘要

本研究嘗試對異向性破裂面之水泥石膏混合試體進行流場觀測之研究。利用自行設計之流場觀測系統，針對四個不同形狀之粗糙面，規劃六個不同案例進行實驗。觀察在不同粗糙度及粗糙面形狀下，其流場行為之變異。在本研究設定之實驗條件下發現：進水位置的不同會對整個流場行為造成差異，而影響到後來流場之波前流向趨勢。當水流由平滑表面進入粗糙表面或由粗糙表面進入平滑表面時，在交界處有先集結再流入（出）粗糙區內的現象。此外，改變粗糙度與流向垂直或平行關係，其流場行為將會明顯不同。裂隙流之流速較穩定，受滯性及附著力影響程度顯著。渠流狀態下多數流速均有減慢之趨勢，在裂隙流狀態有出現下游流速大於中游流速之情形。整體而言，實驗結果與數值分析結果有相同的趨勢。

關鍵字

岩石 ； 破裂 ； 流場

並列摘要

An experiment was established to observe the anisotropic flow through a synthetic rock fracture. The rock fracture was made of a cement-gypsum mixture. In order to study the effect of anisotropy, four different patterns of rough surfaces were planned and six scenarios were investigated. In each scenario, different observations were carried out and the flow conditions were recorded. The experimental results were then compared with the numerical analysis carried out by the program, PDEase2D. This study finds that the different water intake position could cause the discrepancy of the flow condition. The flow appears ＂condensed＂ in the interface between the smooth and rough areas. The condition of roughness and the direction of flow have an effect on the overall flow behavior. The observed flow velocity is laminar according to Reynold's criteria. The fracture flow is strongly influenced by the viscosity and adhesion. In most cases of open channel flow, the flow velocity is observed to decrease downstream. In several cases of fracture flow, the flow velocity is observed to increase downstream. Overall, the numerical simulation of PDEase2D indicates the same trend of the flow pattern as the experimental observation.

並列關鍵字

Rock ； Fracture ； Flow