Page 367 - Air pollution and greenhouse gases from basic concepts to engineering applications for air emission control

11.5 Practice Problems 345

2. On a clear day at night, the wind speed measured at 10 m above the ground is
4 m/s, what is the stability class of the atmosphere? And calculate the wind
speed at 100 m high.
3. In a city center with different buildings, the wind speed measured at 10 m height
is 4 m=s under neutral condition. What is the wind speed at 50 m high?
4. The wind speed at 10 m high under neutral condition is 5.5 m/s, estimate
(a) the wind speed at the stack height of 200 m?
(b) the mixing height with C 0 ¼ 0:3
5. Consider a power plant stack with a diameter of d s ¼ 2 m and the stack emission
gas is discharged at a speed of v s ¼ 5m=s. Assume wind speed u ¼ 2 m/s, and
surrounding air T a ¼ 290 K: Plot the plume rise downwind the emission source
for discharge temperature of T s ¼ 450 K:
6. Same as that described in Problem 4 above, the power plant in a rural area has a
stack of 200 m high with an inner diameter of 2 m. continuously discharge SO 2
3
into the atmosphere at a concentration of 100 mg/m . The discharge air flow rate
3
is 2 million m /hr. On a slightly sunny day, the wind speed at 10 m high is about
5.5 m/s. Ignore the chemical reactions in the atmosphere, and estimate
(a) SO 2 concentration at the center of the plume 4 km downwind from the
stack.
(b) ground level SO 2 concentration 4 km downwind

References and Further Readings

1. Andreas EL (2009) A new value of the von Karman constant: implications and
implementation. J Appl Meteorol Climatol 48:923–944
2. Benoit R (1977) On the integral of the surface layer profile-gradient functions. J Appl
Meteorol 16:859–860
3. Bjorklund JR, Bowers JF (1982) User’s instruction for the SHORTZ and LONGZ computer
programs, vol I–II. EPA Document EPA-903/9-82-004A and B. US EPA, Middle Atlantic
Region III, Philadelphia, Pennsylvania, USA
4. Briggs GA (1965) A plume rise model compared with observations. J Air Pollut Control
Assoc 15(9):433–438
5. Briggs GA (1973) Diffusion estimation for small emissions. Annual Report of Air Resources
Atmospheric Turbulence and Diffusion Laboratory, NOAA Oak Ridge, Tennessee, USA
6. Britter RE, Hanna SR (2003) Flow and dispersion in urban areas. Annu Rev Fluid Mech 2003
(35):469–496
7. Canepa E (2004) An overview about the study of downwash effects on dispersion of airborne
pollutants. Environ Model Softw 19(2004):1077–1087
8. Cheng Y, Brutsaert W (2005) Flux-profile relationship for wind speed and temperature in the
stable atmospheric boundary layer. Bound-Layer Meteorol 114:519–538
9. Foken T (2006) 50 years of the Monin-Obukhov similarity theory. Bound-Layer Meteorol
119:431–447
10. Garrant JR (1990) The internal boundary layer—a review. Bound-Layer Meteorol 50:171–203