URBAN FLUID DYNAMICS - Thermally driven environmental flows Entrainment into the atmospheric boundary layer: lidar observations and LES simulations
نویسندگان
چکیده
Entrainment is the process whereby miscible fluid is exchanged across a density interface bounding a region of turbulent flow [17]. It is of central importance in governing the dynamics of the atmospheric boundary layer (ABL) top. In the exchange process, relatively quiescent fluid is engulfed by turbulent motions penetrating across the interface and is subsequently mixed into the turbulent region. Smaller-scale motion is damped so that a relatively sharp interface is maintained which advances into the quiescent layer causing the turbulent layer to thicken.
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