【作者】 吕亚飞； 刘金； 赵亮； 袁野平； 贺治国；

【Author】 Lv Yafei;Liu Jin;Zhao Liang;Yuan Yeping;He Zhiguo;Ocean College,Zhejiang University;

【机构】 浙江大学海洋学院；

【摘要】 异重流在层结水体中的运动是自然界中的常见现象,其发展过程是工程中较为关注的问题。然而,目前对分层环境中异重流发展过程的定量研究还很少。本文基于"thermal theory"理论,通过在现有公式中加入形状因子来反映异重流驱动力的变化,并考虑了环境水体密度改变对其运动过程的影响,得到了线性分层环境中开闸式斜坡异重流在减速阶段的头部速度公式。采用了"双缸法"生成线性分层水体,并进行了相应的开闸式异重流实验,利用高速相机获取了异重流的头部位置和速度等数据。将公式计算结果与相应实验数据进行了比较,结果表明,本文提出的公式能够有效地预测斜坡异重流在减速阶段的运动过程,这对水利工程、流体力学等相应领域的工程实践有重要的指导意义。更多还原

【Abstract】 Propagation of gravity currents in a stratified environment is a common phenomenon,and it is of great importance in engineering. However,there are very few quantitative studies on the propagation of gravity currents in linearly stratified environments. Based on the ?thermal theory?,a new formula,which considered the influence of ambient stratification and shape on the driving force of lock-exchange gravity currents,was proposed to describe the front velocity at deceleration stage. Series of experiments were conducted in linearly stratified environments produced by a two-tank system. A high-speed camera were used to obtain the data of the front location and velocity of the gravity currents. The calculated results agreed well with the experimental data at the deceleration stage,which meant the formula presented in this paper could well predict the deceleration stage of gravity currents in inclined and linearly stratified environments. This study can provide useful information for hydraulic engineering,fluid mechanics,etc.更多还原