An event-based description of the heat-flux time series in an atmospheric boundary layer

Duration: 23 mins 25 secs

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An event-based description of the heat-flux time series in an atmospheric boundary layer's image

Description:	Narasimha, R (Indian Institute of Science) Thursday 11 September 2008, 15:50-16:10

Created:

2008-10-08 13:39

Collection:

The Nature of High Reynolds Number Turbulence

Publisher:

Isaac Newton Institute

Narasimha, R

Language:

eng (English)

Keywords:

Transition; Turbulence;

Credits:

Author:	Narasimha, R
Photographer:	Steve Greenham


Abstract:	A new method of describing the turbulent momentum flux time series (which we call the ‘extended point-process’ method) has recently been proposed (Narasimha+ 2007 Phil. Trans A). In this method ‘flux events’ are identified in the associated time series, and their characteristics defined in terms of their contributions to the mean flux (so events can be of either sign). We extend the method here to provide a similar description of the eddy heat flux time series, and show the enormous influence exerted by the state of stability of the atmospheric boundary layer on flux-event statistics. A seminar from the Wall Bounded Shear Flows: Transition and Turbulence conference in association with the Newton Institute programme: The Nature of High Reynolds Number Turbulence www.newton.ac.uk/programmes/HRT/seminars/

Abstract:

A new method of describing the turbulent momentum flux time series (which we call the ‘extended point-process’ method) has recently been proposed (Narasimha+ 2007 Phil. Trans A). In this method ‘flux events’ are identified in the associated time series, and their characteristics defined in terms of their contributions to the mean flux (so events can be of either sign). We extend the method here to provide a similar description of the eddy heat flux time series, and show the enormous influence exerted by the state of stability of the atmospheric boundary layer on flux-event statistics.

A seminar from the Wall Bounded Shear Flows: Transition and Turbulence conference in association with the Newton Institute programme: The Nature of High Reynolds Number Turbulence www.newton.ac.uk/programmes/HRT/seminars/

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