BASIC INFORMATION

Full Model Name
WinDimula (version 1.0 is formed by Dimula 2.1 model ad DMS Suite (Diffusion Model Support Suite) for Dimula
Model version and status
Version 1.0 completed (it includes Dimula 2.1 model without modifications)
Version 2.0 under developement
Institutions
MAIND S.r.l. Piazzza L. da Vinci, 7 20133 Milano
ENEA C.R. Casaccia Dip. Ambiente Via Anguillarese, 301 00060 S. Maria di Galeria (Roma)
Contact persons
Dr. Stefano Giarola
Dr. Gianni Grippa
Contact address
MAIND S.r.l. Piazzza L. da Vinci, 7 20133 Milano
Phone number
++39 2 2367490
Fax number
++39 2 2367490
e-mail address
info@maind.it
Intended field of application
Simulation of pollutatnt dispersion in atmosphere at local scale;
regulatory purposes.
Model type and dimension
Gaussian model
Model description summary
WinDimula consists of three separate modules:
Short Term module: it uses "istantaneous" meteorological conditions (wind speed and direction, stability, and temperature) and gives "istantaneous" v alues of concentration into the computational domain;
Climatological module: it uses a statistical aggregation of meteorological conditions (Joint Frequency Function - JFF) over the period (year, sesons..) on wich JFF are derived; WinDimula can treat separately also calm wind class (typical for italian meteorology)
maximun concentration module: it computes the maximun value of concentration at ground and its position considering a monodimensional computational domain. Each module is based on Gaussian solution of diffusion equation;
horizontal and vertical diffusion parameter are function of downwind distance, atmospheric stability, height of inversion and terrain characteristics (roughness);
WinDimula includes also a model for calm conditions (Cirillo; Poli)
Version 2.0 allows concentration computation also in descrete point into the domains at a height different from ground.
Model limitations
Gaussian approximations,
chemical reactions are not included;
orography is treatet in a simple way and only in climatological computations (only in version 1.0);
general limitations for version 1.0 are:
maximum dimension of computational grid = 101x 101 points;
20 elevated point sources;
70 non elevated point sources;
30 area sources;
50 linear sources;
these limitations will be revised in version 2.0
Resolution
Temporal resolution
Depends on temporal resolution of meteorological data: both for Short Term and "Climatological" version.
Horizontal resolution
Depends on applicability of gaussian conditions (for version 1.0 there is the limItation of 101 x 101 grid points; for version 2.0 this limit will depends on computer memory characteristics)
Vertical resolution
Depends on applicability of gaussian conditions
Schemes
Building downwash considered
Orography effects included in climatological computation
Solution technique
Gaussian solution implementation
Input requirements
WinDimula requires one input file subdivided in four set of input informations:
Grid data: dimension (n. of grid points, mesh dimension) coordinates (in Km) of domain origin.
Source data: number and type of source, heigh of emission point, inner diameter , emission rate, exit velocity, exit temperature, settling velocity, open country or urban conditions domain roughness;
Meteorological data: wind velocity and direction, air temperature, atmosphere stability or Join Frequency Function (JFF) for Climatological Computation;
Orographical data: file path containing terrain height for every domain mesh (in version 2.0 also the roughness can be specified in this way for the computational domain);
Output
Concentration values in every domain grid point at ground level (in version 2.0 concentration values are computed also in discrete receptors different from grid points ana at height different from domain height).
User interface
WinDimula runs on PC and has a graphical interface for WINDOWS environment (DMS Suite) for input treatment. output results are treated throgh a "Graphical Analysis" module under WINDOWS included (part of) the model.
User community
The model can be applied both for routine applications related to Impact Assesment Analysis and regulatory purposes.
Previous applications
WinDimula has been applied for routine applications related to Impact Assesment Analysis and regulatory purposes.
Documentation status (help)
WinDimula (1.0) includes an on line hypertextual help and an "How to use" paper manual.
A detailed tutorial (educational module) about the use of the model is under developement and will be included in version 2.0.
All documentation is actually in italian only
Validation and evaluation
WinDimula 1.0 has been validate as Dimula 2.1in several ways expecially against other models (see references).
The code is currently under validation against Model Validation Kit data set (National Environmental Research Institute ( Roschilde Denmark) http://www.dmu.dk/AtmosphericEnvirinment/harmoni.htm
(see references)

PORTABILITY AND COMPUTER REQUIREMENTS

Portability
WinDimula 1.0 has been developed on PC with WINDOWS 95 and it can run also under WINDOWS 98 and NT

CPU Time
A simulation included one point source on a 200 x 200 grid points domain runs in few seconds on a Pentium 500 MHz.

Storage
Installation support consist of about 7 MB of compressed files included also the parts of operating systems used to run the package;
the installation depends on the actual status of operating system on the PC, WinDimula directory only can requires about 6 MB.

REFERENCES
P. Cagnetti , V. Ferrara
Two possible simplified diffusionmodels for very low wind-speed, Rivista di Meteorologia Aeronauitica -V.XLII -N. 4.(1982)

M. Cirillo , P. Cagnetti
DIMULA (modello DiffusioneMULtisorgente Atomsferica): un codice multisoregnte per il calcolo della concentrazione in aria, al livello del suolo, degli inquinanti atmosferici,RTI/STUDI-VALSAMB(82) 8:1-31.

M.C. Cirillo, G.C. Clerici e D. Manzi
Manuale d'uso del codice DIMULA(modello di DIspersione MULtisorgente Atmosferica) - versione 1.0.1986.
Rapporto ENEA RT/STUDI/86/2, 1986.

M.C. Cirillo, G. Clerici e D. Manzi
PC-DIMULA: un modello integrato di dispersione atmosferica multisorgente per personal computer.
Bollettino Geofisico. Anno XI, n. 1, Marzo 1988, pp.154-159.

M.C. Cirillo, G. Finzi, F. Fortezza, G. Mamolini, A. Marani, M.C. Mura, M.Tamponi, T. Tirabassi

Modelli per la progettazione e valutazione di una rete di rilevamento per il controllo della qualità dell'aria
Rapporto ISTISAN (Istituto Superioredi Sanità) 90/32 ISSN-0391-1675, 1990

M.C. Cirillo and D. Manzi
PC DIMULA 2. 0: An Atmospheric Multisource Dispersion Model of AirPollutant on Local Scale.
Environmental Software, 1991, Vol. 6, n. 1, pp.43-48.

M.C. Cirillo, G. Finzi, F. Fortezza, G. Mamolini, A. Marani, M. Tamponi, T.Tirabassi
Modelli matematici a supporto delle reti di controllo della qualità dell'aria

Acqua Aria, No. 8, settembre 1992, pp.733-738

Cirillo M.C. and G. Graziani
Regulatory atmospheric short and medium range dispersion models in Italy.
Workshop on Operational Short-range Atmospheric Dispersion Models for Environmental Impact Assessment in Europe, Mol, Nov. 1994, published in
Int. J. Environment and Pollution,Vol. 5, Nos. 4-6, 1995, pp.450-462

G. Briganti, S. Giarola, G. Grippa, G. Zanini, G. Monforti, M. P. Kolarova
WinDimula model evaluation with the Model Validation Kit
Submitted at "Harmonization within Atmospheric Dispersion Modelling for Regulatory Purposes" conference Belgirate (italy) May 28-31 - 2001

Applications and intercomparison with other models (Dimula 2.1)

M.C. Cirillo, G.C. Clerici and D.Manzi

Atmospheric transport of sulphur dioxide on a local scale: a case study
In "Modelling in Ecotoxicology", S.E. Jørgensen Editor, Elsevier, 1990,pp.173-195.

R. Bianconi, M.C. Cirillo, G.Giannotti, S. Mosca, M. Tamponi, G. Tebaldi, T. Tirabassi
Analisi di sensibilità per alcuni modelli di dispersione di inquinanti primari in atmosfera: il DIMULA, l'ISCed il KAPPAG
Acqua Aria, No. 5 Maggio 1991, pp.479-487.

M. Cirillo , A. Poli
An intercomparison of semiempirical diffusion models under low wind speed, stable conditions, Atmospheric Environment (1992) Vol. 26A, No. 5,pp. 765-774.

A. Cucchieri, M.C. Cirillo e D. Gaudioso
L'inquinamento atmosferico da centrali termoelettriche nell'alto Lazio.
Acqua Aria, N. 8, settembre 1993, pp.893-895

D. Manzi , E. Ripamonti
Analisi delle prestazioni dei modelli:DIMULA e ISC a confronto in un caso critico, Acqua-Aria -3 (1994).

Cirillo M.C., Coppi R., Pittau M.G., RomanoD.
Metodologie ottimali per la progettazione di reti di monitoraggio della qualità dell'aria. Ingegneria Ambientale,vol. XXIII, n. 11-12, nov.-dic. 1994, pp. 628-636.

Metallo M.C., A.A. Poli, M. Diana, F.Persia and M.C. Cirillo
Air pollution loads on historical monuments: an air quality model application to the marble Arch of Titus inRome.
The Science of the Total Environment, 171, 1995, pp. 163-172

P.Del Buono, C. Brofferio, S. Racalbuto
Applicazione di modelli standardizzati di diffusione atmosferica all' area ad elevata concentrazione industriale di Taranto: confronti e linee di sviluppo.(1997) in pubblicazione