CCC-0383 DWNWND.

1. NAME OR DESIGNATION OF PROGRAM:  DWNWND.

3. DESCRIPTION OF PROBLEM OR FUNCTION

DWNWND estimates the atmosphe-  ric concentration and deposition of material downwind from its point of release by the Gaussian plume atmospheric dispersion model.

4. METHOD OF SOLUTION

The model uses empirically determined disper- sion factors for different release heights and meteorological and terrain conditions. The user may specfy any of eight different sets  of dispersion parameters: Pasquill-Gifford, Briggs-Smith, Briggs, Klug, Brookhaven, St. Louis, Juelich (50 m release height), and Juelich (100 m release height). Using the selected dispersion para-  meters, ground-level normalized exposure estimates are made at any specified downwind distance for the plume centerline and for the 22.5 degree sector average. Computed values may be corrected for plume depletion due to deposition and for plume settling due to gravitational fall.

5. RESTRICTIONS ON THE COMPLEXITY OF THE PROBLEM:

6. TYPICAL RUNNING TIME

Each simulation requires less than one second of CPU time on the PDP-10.

7. UNUSUAL FEATURES OF THE PROGRAM

The program is written for inter-  active operation on the PDP-10 computer.

8. RELATED AND AUXILIARY PROGRAMS:

10. REFERENCES

- J. Barish in G.W. Westley, J.A. Watts, eds.: The Computing Technology Center Numerical Analysis Library Union Carbide Corporation Nuclear Division, Computing Technology Center Report CTC-39, pp. 76-80 (1970) - A.A. Brooks, E.C. Long in G.W. Westley, J.A. Watts (editors): The Computing Technology Center Numerical Analysis Library Union Carbide Corporation Nuclear Division, Computing Technology Center Report CTC-39, pp. 2-6 (1970)
- W.M. Culkowski, M.R. Patterson: A Comprehensive Atmospheric Transport and Diffusion Model ORNL/NSF/EATC-17 (1976)
- H. Geiss, K.J. Vogt, H.S. Ehrlich, G. Polston: Recent Results of Dispersion Experiments at Emission Heights of 50 and 100 m Proceedings of the 12th Annual Symposium of the German-Swiss Fachverband fuer Strahlenschutz October 2-6, 1978 English Translation: OLS-79-43 - F.A. Gifford: Turbulent Diffusion - Typing Schemes: A Review Nuclear Safety 17(1), p. 68 (1976)
- F.A. Gifford,Jr., D.H. Pack: Surface Deposition of Airborne Material Nuclear Safety 3(4), p. 76 (1962)
- W.F. Hilsmeier, F.A. Gifford: Graphs for Estimating Atmospheric Dispersion U.S. Weather Bureau Report ORO-545 (1962)
- R.P. Hosker,Jr.: Estimates of Dry Deposition and Plume Depletion over Forests and Grasslands in: Physical Behavior of Radioactive Contaminants in the Atmosphere Proceedings of a Symposium, Vienna, Austria, 12-16 November 1973 STI/PUB/354 (1974)
- J.L. McElroy, F. Pooler, Jr.: St. Louis Dispersion Study Vol. II, Analysis. U.S. Department of Health, Education, and Welfare National Air Pollution Control Administration (1968)
- C.W. Miller, F.O. Hoffman, D.L. Shaeffer: The Importance of Variation in the Deposition Velocity for the Assessment of Airborne Radionuclide Releases Health Physics 34(5), p. 730 (1978)
- R.E. Moore: The AIRDOS-II Computer Code for Estimating Radiation Dose to Man from Airborne Radionuclides in Areas Surrounding Nuclear Facilities ORNL-5245 (1977)
- B.D. Murphy: Deposition of SO2 on Ground Cover in Proceedings of Third Symposium on Atmospheric Turbulence, Diffusion, and Air Quality American Meteorological Society (1976a)
- B.D. Murphy: The Influence of Ground Cover on the Dry Deposition Rate of Gaseous Materials UCCND/CSD-19 (1976b)
- F. Pasquill: The Estimation of the Dispersion of Wind-Borne Material Meterol. Mag. 90, p. 33 (1961)
- F. Pasquill: Atmospheric Diffusion 2nd Edition, Ellis Horwood, Ltd., Chichester, England (1974)
- F. Pasquill: The Gaussian Plume Model with Limited Vertical Mixing EPA-600/4-76-042 (1976)
- D.H. Slade, ed.: Meteorology and Atomic Energy (1968) TID-24190
- I.A. Singer, M.E. Smith: Atmospheric Dispersion at Brookhaven National Laboratory Int. J. Air Water Pollut. 10, p. 125 (1966)
- K.J. Vogt: Empirical Investigations of the Diffusion of Waste Air Plumes in the Atmosphere Nucl. Technol. 34, pp. 43-57 (1977)

- D.E. Fields and CH.W. Miller:
User's Manual for DWNWND - An Interactive Gaussian Plume Atmospheric Transport
Model with Eight Dispersion Parameter Options ORNL/TM-6874 (May 1980).
- Output DWNWND NEADB Note (19/04/83).

11. MACHINE REQUIREMENTS:

13. OPERATING SYSTEM UNDER WHICH PROGRAM IS EXECUTED:

NEA-DB ran the test cases on PDP-11/70 under IAS using  the FOR/F4P compiler.

14. OTHER PROGRAMMING OR OPERATING INFORMATION OR RESTRICTIONS:

15. NAME AND ESTABLISHMENT OF AUTHOR

Contributed by:   Radiation Safety Information Computational Center
                  Oak Ridge National Laboratory
                  Oak Ridge, Tennessee, U.S.A.
Developed by:     Oak Ridge National Laboratory, Oak Ridge, Tennessee, USA

File name	File description	Records
CCC0383_01.003	DWNWND INFORMATION FILE	48
CCC0383_01.004	DWNWND SOURCE PROGRAM (FORTRAN-4)	473