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Concentration, units & dimensions

Learning Objectives:

Define Environmental Fluid Mechanics (EFM)

List and define three types of concentrationmeasures

List the dimensions of concentration, massfraction, and the diffusion coefficient

Convert concentration measures amongvarious units (i.e. mg/l to mol/l)

Motivational Question:

How do you quantify the amount of a

chemical dispersed in the environment?

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Examples of EnvironmentalFluid Mechanics Projects

OCEN 489 and 689Scott A. Socolofsky

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Environmental Fluid Mechanics

Definition: Answers to how natural processesin the hydrosphere change concentrations

Transport processes:

Diffusion (molecular and turbulent)

Advection

Transformation processes: (key processes)

Dissolution

Chemical reactions

Critter metabolisms

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Transport in the Hydrosphere

Courtesy of Chin Wu.

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Concentrations

Concentrationboundary layer.Turbulencestructure isclearly evident.

Waves collage courtesy of John Crimaldi

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Hydromechanics

Breaking wavesmove sediment,generate seaspray, oxygenatethe water columnand provideturbulence,among otherimportant coastaland offshoreprocesses

Courtesy of Benoit Cushman-Roisin, DartmouthCollege

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Point Pollution Sources

WastewaterOutfalls

Courtesy of the CORMIX project

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Non-Point Pollution Sources

Courtesy of Roanoke County, VA

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Storm Water Runoff

Pollutant loadsinclude point andnon-pointsources

Courtesy of USGS

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Water Quality

Measurement ofa wealth of waterqualityparameters

Courtesy of Cortland College

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Limnology

Zooplankton,phytoplankton,and other lakeinhabitants

Courtesy of Gertrud Cronberg

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Natural Preservation

RestorationandProvisionfor NaturalConditions

Courtesy of College of Natural Resources, University of Idaho

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TopicsDiffusion

Advection

River Mixing Processes

Transformation

Air/water Interface

Sediment/water Interface

Tidal Mixing

Point source near-field: Jets and Plumes

Environmental fate and transport modeling