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Exercises


Coordinate System

Central Campus Map


CALINE 4

 

Job Parameters

Link Geometry

Link Activity

Run Conditions

Model Output


 

 

Central Campus Air Quality Model (CCAQM) Instructions

 

·         Job Parameters

 

 

o      Run Type - Different choices determine averaging times (for CO concentrations) and how the hourly average wind angle(s) will be determined.  (Wind angle is the angle between the roadway link and the wind direction.  CALINE4 calculates the angles based on data in the Link Geometry and Run Conditions Screens.)  Most users should invoke the "worst-case wind angle" run type and apply a persistence factor of 0.6 to 0.7 in order to estimate an 8-hour average CO concentration.

 

§      Standard - Calculates 1-hour average CO concentrations at the receptors.  The user must input a wind direction on the Run Conditions Screen.

§      Multi-Run - Calculates 8-hour average CO concentrations at the receptors.  The user must input wind angles for each hour.

§      Worst-case wind angle - Calculates 1-hour average CO concentrations at the receptors.   The model selects the wind angles that produce the highest CO concentrations at each of the receptors.  This is the most appropriate choice for most users.

§      Multi-Run/Worst-Case hybrid - Calculates 8-hour average CO concentrations at the receptors.  The model selects the wind angles that produce the highest CO concentrations at each of the receptors.
 

o      Aerodynamic Roughness Coefficient - These choices determine the amount of local air turbulence that affects plume spreading.  CL4 offers the following 4 choices for aerodynamic roughness coefficient:

§         Rural: Roughness Coefficient = 10 cm

§         Suburban: Roughness Coefficient = 100 cm

§         Central Business District: Roughness Coefficient = 400 cm

§         Other
 

o     Model Information - Provides summary information for convenience and quality assurance.