Generic Guidance and Optimum Model Settings for the CALPUFF ...

Figure 3-5 GUI screenshot from CALPRO showing the CALPUFF user input control
screen for the average properties for line sources.
The average buoyancy parameter is used in the plume rise equations. For multiple line sources of
comparable buoyancy flux, the buoyancy parameter is calculated for each line source and then
averaged.
If using the slug model, the maximum number of segments for each line is the maximum number
of line segments into which each line can be divided. The default is 7. If using the puff model
this parameter is the actual number of virtual point sources used to represent each line.
Buoyant Line Source Modeling Summary
– Line source plume rise has a different functional relationship with buoyancy and
distance than point source plume rise
– Other effects include directionality and multiple source enhancement effects
– Cannot reproduce proper line source buoyant rise with point source plume rise
model (potentially large under or over estimation of impacts)
– Treatment of buoyant line sources such as potrooms as non-buoyant volume
sources significantly underestimates plume heights and overestimates
concentrations.
– Non-buoyant lines can be represented by a series of volume or point sources, but
buoyant lines cannot be properly represented in this way
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