突然释放型浊流在不同坡折渠道中的流动与沉积  

Numerical Simulation of Flow and Deposition of Sudden Release Turbidity on Different Slope Breaks

作　　者：季雪瓜 陶丽云 黄河清[1] JI XueGua;TAO LiYun;HUANG HeQing(Research Institute of Environmental Fluid,Anhui University of Technology,Maanshan,Anhui 243000,China)

机构地区：[1]安徽工业大学环境流体研究所,安徽马鞍山243000

出　　处：《沉积学报》2022年第3期730-738,共9页Acta Sedimentologica Sinica

基　　金：国家自然科学基金(40972086,41172103,4137071)。

摘　　要：应用雷诺平均纳维尔—斯托克斯模型模拟探讨了等量突然释放型浊流在流经不同坡折渠道的流动及沉积特性,取得如下主要结论:随着底坡增加,浊流流速增长率因卷吸作用的增强而减缓;浊流深度平均速度和浓度形态相似,头部大且向尾部呈线性下降;在小坡折处产生沉积,沉积最厚处离坡折处不远且上下游平均粒径相差不大,往下游厚度呈线性减小;而在大坡折处产生侵蚀,随着坡度的增大侵蚀增加,沉积最厚处离坡折处较远且上下游平均粒径相差大,形态上呈上拱状。这些认识对于根据浊流沉积特征推测其形成环境具有一定的参考作用。This work studied the flow and deposition of sudden-release turbidity currents with equal initial volume passing over different slope breaks by applying the Bussinesq-assumption adopted RANS model. The following main conclusions are obtained:the growth rate of the current velocity becomes slower with the bed slope increasing due to the enhancement of entrainment;the depth-averaged speed and concentration are similar in that they are big at head and linear decreasing towards the tail. Deposit occurs at the small slope break,the thickest deposition is not far from the slope break,the average particle size of the upstream and downstream is not much different,and toward the downstream thickness decreases linearly. Erosion occurs at larger slope break. With slope increasing this erosion deepens and deposition happens further from the slope break and the average particle diameter of the upstream and downstream varies greatly,and the deposition is arched in shape. These understandings have a certain reference role in predicting the formation environment according to the characteristics of turbid current deposition.

关 键 词：浊流 数值模拟 突然释放型 流动和沉积 

分 类 号：P736.2[天文地球—海洋地质]