Passive scalar mixing and decay at finite correlation times in the Batchelor regime

نویسندگان
چکیده

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Scalar variance decay in chaotic advection and Batchelor-regime turbulence.

The decay of the variance of a diffusive scalar in chaotic advection flow (or equivalently Batchelor-regime turbulence) is analyzed using a model in which the advection is represented by an inhomogeneous baker's map on the unit square. The variance decays exponentially at large times, with a rate that has a finite limit as the diffusivity kappa tends to zero and is determined by the action of t...

متن کامل

Turbulent Decay of a Passive Scalar in Batchelor Limit: Exact Results from a Quantum-Mechanical Approach

We show that the decay of a passive scalar θ advected by a random incompressible flow with zero correlation time in Batchelor limit can be mapped exactly to a certain quantum-mechanical system with a finite number of degrees of freedom. The Schrödinger equation is derived and its solution is analyzed for the case when at the beginning the scalar has Gaussian statistics with correlation function...

متن کامل

Anomalous scaling for a passive scalar near the Batchelor limit

A class of phenomenological Hopf equations describing mixing of a passive scalar by random flow close to the Batchelor limit ~i.e., advection by random strain and vorticity! is analyzed. In the Batchelor limit multipoint correlators of the scalar are constructed explicitly by exploiting the SL (N ,R) symmetry of the Hopf operator. Hopf equations close to this ‘‘integrable’’ limit are solved via...

متن کامل

Universal long-time properties of Lagrangian statistics in the Batchelor regime and their application to the passive scalar problem.

We consider the transport of dynamically passive quantities in the Batchelor regime of a smooth in space velocity field. For the case of arbitrary temporal correlations of the velocity, we formulate the statistics of relevant characteristics of Lagrangian motion. This allows us to generalize many results obtained previously for strain delta correlated in time, thus answering a question about th...

متن کامل

Scalar Decay in Chaotic Mixing

I review the local theory of mixing, which focuses on infinitesimal blobs of scalar being advected and stretched by a random velocity field. An advantage of this theory is that it provides elegant analytical results. A disadvantage is that it is highly idealised. Nevertheless, it provides insight into the mechanism of chaotic mixing and the effect of random fluctuations on the rate of decay of ...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Journal of Fluid Mechanics

سال: 2017

ISSN: 0022-1120,1469-7645

DOI: 10.1017/jfm.2017.364