کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
1897645 1044558 2012 9 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Understanding and modeling turbulent fluxes and entrainment in a gravity current
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات ریاضیات کاربردی
پیش نمایش صفحه اول مقاله
Understanding and modeling turbulent fluxes and entrainment in a gravity current
چکیده انگلیسی

We present an experimental study of the mixing processes in a gravity current flowing on an inclined plane. The turbulent transport of momentum and density can be described in a very direct and compact form by a Prandtl mixing length model: the turbulent vertical fluxes of momentum and density are found to scale quadratically with the vertical mean gradients of velocity and density. The scaling coefficient, the square of the mixing length, is approximately constant over the mixing zone of the stratified shear layer. We show how, in different flow configurations, this length can be related to the shear length of the flow (ε/∂zu3)1/2(ε/∂zu3)1/2. We also study the fluctuations of the momentum and density turbulent fluxes, showing how they relate to mixing and to the entrainment/detrainment balance. We suggest a quantitative measure of local entrainment and detrainment derived from observed conditional correlations of density flux and density or vertical velocity fluctuations.


► We present a study of mixing processes in a gravity current flowing on an inclined plane.
► The turbulent fluxes scale quadratically with the vertical mean gradients.
► The scaling coefficient can be related to the shear length of the flow (ε/∂zu3)1/2(ε/∂zu3)1/2.
► The fluctuations of turbulent fluxes relate to the entrainment/detrainment balance.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Physica D: Nonlinear Phenomena - Volume 241, Issue 3, 1 February 2012, Pages 260–268
نویسندگان
, , ,