On Stationarity of Lagrangian Observations of Passive Tracer Velocity in a Compressible Environment
نویسندگان
چکیده
We study the transport of a passive tracer particle in a steady strongly mixing flow with a non-zero mean velocity. We show that there exists a probability measure, under which the particle Lagrangian velocity process is stationary. This measure is absolutely continuous with respect to the underlying probability measure for the Eulerian flow.
منابع مشابه
On Stationarity of Lagrangian Observations of Passive Tracer Velocity in a Compressible
Here u= (u1, . . . , ud) :R d ×Ω→ Rd is the Eulerian velocity field of the flow. It is assumed to be a stationary, d-dimensional random vector field given over a certain probability space (Ω,V,P), and w(·) is a standard d-dimensional Brownian motion defined over another probability space (Σ,A,Q). Parameter κ, called the molecular diffusivity of the medium, is assumed to be nonnegative. The resu...
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