断面曲率半径对海底浊流的影响  

Influences of Cross-sectional Curvature on Turbidity Currents in Sinuous Submarine Canyons

作　　者：郭彦英[1] 张家年[1] 周宗鹏[1] 黄河清[1] 

机构地区：[1]安徽工业大学建筑工程学院环境流体研究所,安徽马鞍山243032

出　　处：《安徽工业大学学报（自然科学版）》2013年第3期240-244,254,共6页Journal of Anhui University of Technology（Natural Science）

基　　金：国家自然科学基金课题(40972086;41172103)

摘　　要：基于雷诺平均的纳维尔-斯托克斯模型,三维数值模拟研究海底浊流在断面顶宽相同、但曲率半径不同的2个圆弧形弯曲渠道内的流动及沉积。结果表明:断面曲率半径大、边坡平缓渠道内的浊流更易在弯道顶点及其下游处发生溢流,而断面曲率半径小、边坡较陡的渠道浊流更易对边坡形成侵蚀,使浊流在渠道内流至下游时依然保持较高的流速及强度;经多次浊流事件的侵蚀及沉积,圆弧形的渠道渐渐向不对称的梯形转换;提高流向坡度会改变弯道顶点中心处二次流的方向。A three-dimensional computational model based on Reynolds-averaged Navier-Stokes equation was used to study the flow and deposition of turbidity currents in two sinuous submarine canyons with the same cross-sectional top width but different curvature. The important findings are： for sinuous channel with higher cross-sectional curvature, turbidity current within the channel are more likely to spill over the bank of the channel bend apex and its downstream, while for channel with lower cross-sectional curvature, erosion occurs more easily and thus maintains relatively strong current downstream; channels with arc cross section gradually transform to asymmetric trapezoidal shape after erosion and deposition of multiple events of turbidity currents; increasing downstream slope may change the direction of bed secondary flow at the center of sinuous channel bend apex.

关 键 词：曲率半径 三维模拟 浊流 流动和沉积 二次流 

分 类 号：X143[环境科学与工程—环境科学]