where

F(T T)w ris the stack momentum flux, is the stack buoyantm s s s= 2 2F gw r(T T)b s s s= 2 Δflux,

rsis the stack radius corrected for stack tip downwash, and $

1(= 0.6) is an entrainmentparameter. It should be noted that

upis the wind speed used for calculating plume rise. In theCBL

upis set equal tou{hs}.As shown in Figure 14, the indirect plume, which is included to treat the no flux condition at

z = zi, is modeled as a reflected version of the direct plume with an adjustment ()hi) to thereflected plume height to account for the delay in vertical mixing due to plume lofting at the top

of the boundary layer. That height adjustment is given by

where

ryandrzare the lofting plume half-widths in the lateral and vertical directions,upis thewind speed used for plume rise, and "

r= 1.4. The produce of cross-wind dimensions of theassumed elliptical plume is calculated from Weil et al. (1997) as

where , $

2= 0.4, 8

y r(z h) = 2.3, andae= 0.1 (dimensionless entrainment parameter).h i s= − β2

For a derivation and discussion of )

hisee Weil et al. (1997).The height that the penetrated source achieves above

ziis calculated as the equilibrium plumerise in a stratified environment and is determined by the source buoyancy flux, the stable

stratification above

zi, and the mean wind speed. In line with Weil et al. (1997), the penetratedsource plume height,

hep, is taken as the centroid of plume material above the inversion. Forcomplete penetration (

fp = 0)hep = hs+)heq. However, for partial penetration (fp > 0),hepischosen as the average of the heights of the upper plume edge

hs +1.5 )heqandzi, orwhere )

heqis defined in eq. (56).5.6.2 PLUME RISE IN THE SBL

Plume rise in the SBL is taken from Weil (1988b), which is modified by using an iterative

approach which is similar to that found in Perry et al. (1989). When a plume rises in an

atmosphere with a positive potential temperature gradient, plume buoyancy decreases because the

ambient potential temperature increases as the plume rises; thus, plume buoyancy with respect to

the surroundings decreases. To account for this, the plume rise equations have to be modified.

With this modification, AERMOD computes stable plume rise, )

hs, from Weil et al. (1988b) as

n951 - n952 - n953 - n954 - n955 - n956 - n957 - n958 - n959 - n960 - n961 - n962 - n963 - n964 - n965 - n966 - n967 - n968 - n969 - n970 - n971 - n972 - n973 - n974 - n975 - n976 - n977 - n978 - n979 - n980 - n881 - n982 - n983 - n984 - n985 - n986 - n987 - n988 - n989 - n990 - n991 - n992 - n993 - n994 - n995 - n996 - n997 - n998 - n999 - n1000

castellano: DISPER CUSTIC DESCAR RADIA italiano:

castellano: DIS CUS DES RAD english: DIS CUS DES RAD

português: DIS CUS DES RAD italiano: DIS CUS DES RAD