A large-eddy simulation far a point source emission has been compared
with four practical dispersion models suitable for regulatory purposes
, and with atmospheric measurements. The large-eddy simulation calcula
tes the turbulent velocity field in detail and uses this to solve the
conservation equation for the pollutant. The practical models are vari
ants of the Gaussian plume model. The measurements are taken from the
Copenhagen dispersion dataset. The measured values lie roughly in the
middle of the broad range of concentrations that follows from the mode
ls.