Numerical modelling of the aerial drop of firefighting agents by fixed-wing aircraft. Part I: model development
J. H. Amorim
+ Author Affiliations
- Author Affiliations
Centre for Environmental and Marine Studies (CESAM), Department of Environment and Planning, University of Aveiro, 3810-193 Aveiro, Portugal. Email: amorim@ua.pt
International Journal of Wildland Fire 20(3) 384-393 https://doi.org/10.1071/WF09122
Submitted: 30 October 2009 Accepted: 27 July 2010 Published: 5 May 2011
Abstract
The efficiency of the aerial drop of firefighting agents (water and retardants) is extremely dependent on pilot skills in dealing with complex atmospheric conditions, mostly because on-board systems for computer-assisted drops have not yet been used operationally. Hence, numerical modelling tools can be of primary importance for the optimisation of firefighting operations and in the testing of new chemical products. The current work addresses the development of the operational Aerial Drop Model. This numerical tool allows a near real-time simulation of aerial drops with fixed-wing aircraft, while covering the fundamental stages of the process. It copes with a wide range of product viscosities, from water to highly thickened long-term retardants. The Aerial Drop Model simulates the continuous stripping of droplets from the liquid jet by the action of Rayleigh–Taylor and Kelvin–Helmholtz instabilities applying the linear stability theory. The subsequent secondary breakup and deformation of the formed droplets due to aerodynamic forces is based on experimental correlations defined in terms of the dimensionless Weber number. Droplet trajectories are computed by applying a Lagrangian approach, in which a dynamical drag module accounts for the effect of deformation. This operational tool provides an improved understanding of the behaviour and effectiveness of aerially delivered firefighting liquids.
Additional keywords: drop effectiveness, droplet flow, forest fires.
References
Amorim JH (2008) Numerical modelling of the aerial drop of products for forest firefighting. PhD Thesis, University of Aveiro, Portugal.Amorim JH (2011) Numerical modelling of the aerial drop of products for forest firefighting. Part II: model validation. International Journal of Wildland Fire 20, 394–406.
| Numerical modelling of the aerial drop of products for forest firefighting. Part II: model validation.Crossref | GoogleScholarGoogle Scholar |
Amorim JH, Miranda AI, Borrego C, Varela V (2006) Recent developments on retardant aerial drop modelling for operational purposes. In ‘Proceedings of the 5th International Conference on Forest Fire Research’, 27–30 November 2006, Figueira da Foz, Portugal. (Ed. DX Viegas) (CD-ROM) (Millpress: Rotterdam)
Andersen WH, Brown RE, Kato KG, Louie NA (1974a) Investigation of rheological properties of aerial-delivered fire retardant – Final report. USDA Forest Service, Intermountain Research Station, Report 8990-04. (Ogden, UT)
Andersen WH, Brown RE, Louie NA, Blatz PJ, Burchfield JA (1974b) Investigation of rheological properties of aerial-delivered fire retardant extended study – Final report. USDA Forest Service, Intermountain Research Station, Report 8990-05. (Ogden, UT)
Andersen WH, Brown RE, Louie NA, Kato KG, Burchfield JA, Dalby JD, Zernow L (1976) Correlation of rheological properties of liquid fire retardant with aerially delivered performance – Final report. USDA Forest Service, Intermountain Research Station, Report 8990-08. (Ogden, UT)
Asner GP, Scurlock JMO, Hicke JA (2003) Global synthesis of leaf area index observations: implications for ecological and remote sensing studies. Global Ecology and Biogeography 12, 191–205.
| Global synthesis of leaf area index observations: implications for ecological and remote sensing studies.Crossref | GoogleScholarGoogle Scholar |
Beale JC, Reitz RD (1999) Modeling spray atomization with the Kelvin–Helmholtz/Rayleigh–Taylor hybrid model. Atomization and Sprays 9, 623–650..
Belcher SE, Jerram N, Hunt JCR (2003) Adjustment of a turbulent boundary layer to a canopy of roughness elements. Journal of Fluid Mechanics 488, 369–398.
| Adjustment of a turbulent boundary layer to a canopy of roughness elements.Crossref | GoogleScholarGoogle Scholar |
Calogine D, Rimbert N, Séro-Guillaume O (2007) Modelling of the deposition of retardant in a tree crown during fire fighting. Environmental Modelling & Software 22, 1654–1666.
| Modelling of the deposition of retardant in a tree crown during fire fighting.Crossref | GoogleScholarGoogle Scholar |
Cescatti A, Marcolla B (2004) Drag coefficient and turbulence intensity in conifer canopies. Agricultural and Forest Meteorology 121, 197–206.
| Drag coefficient and turbulence intensity in conifer canopies.Crossref | GoogleScholarGoogle Scholar |
Crowe C, Sommerfeld M, Tsuji Y (1998) ‘Multiphase Flows with Droplets and Particles.’ (CRC Press: Florida)
Finney MA (1998) FARSITE: Fire Area Simulator – model development and evaluation. USDA Forest Service, Rocky Mountain Research Station, Research Paper RMRS-RP-4. (Ogden, UT)
Finnigan J (2000) Turbulence in plant canopies. Annual Review of Fluid Mechanics 32, 519–571.
| Turbulence in plant canopies.Crossref | GoogleScholarGoogle Scholar |
Finnigan JJ, Brunet Y (1995) Turbulent airflow in forests on flat and hilly terrain. In ‘Wind and Trees’. (Eds MP Coutts, J Grace) pp. 3–40. (Cambridge University Press: Cambridge, UK)
George CW, Blakely AD (1973) An evaluation of the drop characteristics and ground distribution patterns of forest fire retardants. USDA Forest Service, Intermountain Research Station, Research Paper INT-134. (Ogden, UT)
George CW, Johnson GM (1990) Developing air tanker performance guides. USDA Forest Service, Intermountain Research Station, General Technical Report INT-268. (Ogden, UT)
Giménez A, Pastor E, Zárate L, Planas E, Arnaldos J (2004) Long-term forest fire retardants: a review of quality, effectiveness, application and environmental considerations. International Journal of Wildland Fire 13, 1–15.
| Long-term forest fire retardants: a review of quality, effectiveness, application and environmental considerations.Crossref | GoogleScholarGoogle Scholar |
Grah RA, Wilson CC (1944) Some components of rainfall interception. Journal of Forestry 42, 890–898..
Haider A, Levenspiel O (1989) Drag coefficient and terminal velocity of spherical and non-spherical particles. Powder Technology 58, 63–70.
| Drag coefficient and terminal velocity of spherical and non-spherical particles.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL1MXktV2mtL4%3D&md5=332984c454747bad85da676fc4ab2fefCAS |
Harman I, Finnigan J (2007) A simple unified theory for flow in the canopy and roughness sublayer. Boundary-Layer Meteorology 123, 339–363.
| A simple unified theory for flow in the canopy and roughness sublayer.Crossref | GoogleScholarGoogle Scholar |
Högström U (1996) Review of some basic characteristics of the atmospheric surface layer. Boundary-Layer Meteorology 78, 215–246.
| Review of some basic characteristics of the atmospheric surface layer.Crossref | GoogleScholarGoogle Scholar |
Hsiang L-P, Faeth GM (1992) Near-limit drop deformation and secondary breakup. International Journal of Multiphase Flow 18, 635–652..
| Near-limit drop deformation and secondary breakup.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3sXmt1ejtw%3D%3D&md5=ff1eedd86bd784ba70da92eb75adf22cCAS |
Hsiang L-P, Faeth GM (1995) Drop deformation and breakup due to shock wave and steady disturbances. International Journal of Multiphase Flow 21, 545–560.
| Drop deformation and breakup due to shock wave and steady disturbances.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK2MXmsFWgsr8%3D&md5=3a329dfd7e0165a4534307f5af1a7fd3CAS |
Inoue E (1963) The environment of plant surfaces. In ‘Environment Control of Plant Growth’. (Ed. LT Evans) pp. 23–32. (Academic Press: New York)
IPCC (2007) ‘Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change.’ (Eds RK Pachauri, A Reisinger) (Intergovernmental Panel on Climate Change: Geneva)
Lee CS, Park SW (2002) An experimental and numerical study on fuel atomization characteristics of high-pressure diesel injection sprays. Fuel 81, 2417–2423.
| An experimental and numerical study on fuel atomization characteristics of high-pressure diesel injection sprays.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD38XmvF2rs7k%3D&md5=a73961e97dc508242ee0cb604c95276fCAS |
Lin SP, Reitz RD (1998) Drop and spray formation from a liquid jet. Annual Review of Fluid Mechanics 30, 85–105.
| Drop and spray formation from a liquid jet.Crossref | GoogleScholarGoogle Scholar |
Linne MA, Paciaroni M, Gord JR, Meyer TR (2005) Ballistic imaging of the liquid core for a steady jet in crossflow. Applied Optics 44, 6627–6634.
| Ballistic imaging of the liquid core for a steady jet in crossflow.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2MXht1Cit7bF&md5=a9302d9589b53190aee9c8ecc45d5288CAS | 16270551PubMed |
Liu H (2000) ‘Science and Engineering of Droplets: Fundamentals and Applications.’ (William Andrew Inc.: New York)
Madabhushi RK (2003) A model for numerical simulation of breakup of a liquid jet in crossflow. Atomization and Sprays 13, 413–424.
| A model for numerical simulation of breakup of a liquid jet in crossflow.Crossref | GoogleScholarGoogle Scholar |
Monin AS, Yaglom AM (1971) ‘Statistical Fluid Mechanics: Mechanisms of Turbulence – Vol. 1.’ (The Massachusetts Institute of Technology (MIT) Press: Cambridge, MA, USA)
Morsi SA, Alexander AJ (1972) An investigation of particle trajectories in two-phase flow systems. Journal of Fluid Mechanics 55, 193–208.
| An investigation of particle trajectories in two-phase flow systems.Crossref | GoogleScholarGoogle Scholar |
Novak MD, Warland JS, Orchansky AL, Ketler R, Green S (2000) Wind tunnel and field measurements of turbulent flow in forests. Part 1: uniformly thinned stands. Boundary-Layer Meteorology 95, 457–495.
| Wind tunnel and field measurements of turbulent flow in forests. Part 1: uniformly thinned stands.Crossref | GoogleScholarGoogle Scholar |
Physick WL, Garratt JR (1995) Incorporation of a high-roughness lower boundary into a mesoscale model for studies of dry deposition over complex terrain. Boundary-Layer Meteorology 74, 55–71.
| Incorporation of a high-roughness lower boundary into a mesoscale model for studies of dry deposition over complex terrain.Crossref | GoogleScholarGoogle Scholar |
Raju MS (2005) Numerical investigation of various atomization models in the modeling of a spray flame. National Aeronautics and Space Administration (NASA) Report E-15389. (Washington, DC) Available at http://gltrs.grc.nasa.gov/reports/2005/CR-2005-214033.pdf [Verified 23 March 2011]
Raupach MR, Thom AS (1981) Turbulence in and above plant canopies. Annual Review of Fluid Mechanics 13, 97–129.
| Turbulence in and above plant canopies.Crossref | GoogleScholarGoogle Scholar |
Reitz RD (1987) Modeling atomization processes in high-pressure vaporizing sprays. Atomization and Spray Technology 3, 309–337..
Reitz RD, Bracco FV (1982) Mechanism of atomization of a liquid jet. Physics of Fluids 25, 1730–1742.
| Mechanism of atomization of a liquid jet.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL3sXnsVGhuw%3D%3D&md5=34b8a59bd60f2543563a9938ca655f03CAS |
Rimbert N, Calogine D, Séro-Guillaume O (2002) Modelling of retardant dropping and atomisation. In ‘Proceedings of the 4th International Conference on Forest Fire Research’, 18–23 November 2002, Luso, Coimbra, Portugal. (Ed. DX Viegas) (CD-ROM) (Millpress: Rotterdam)
Séro-Guillaume O, Rimbert N (2005) On thermodynamic closures for two-phase flow with interfacial area concentration transport equation. International Journal of Multiphase Flow 31, 897–920.
| On thermodynamic closures for two-phase flow with interfacial area concentration transport equation.Crossref | GoogleScholarGoogle Scholar |
Simmons HC (1977) The correlation of drop-size distribution in fuel-nozzle sprays. Journal of Engineering for Gas Turbines and Power 99, 309–319..
Stroppiana D, Boschetti M, Confalonieri R, Bocchi S, Brivio PA (2006) Evaluation of LAI-2000 for leaf area index monitoring in paddy rice. Field Crops Research 99, 167–170.
| Evaluation of LAI-2000 for leaf area index monitoring in paddy rice.Crossref | GoogleScholarGoogle Scholar |
Swanson DH, Helvig TN (1973) High-altitude retardant drop mechanization study. Honeywell Inc., Government and Aeronautical Products Division, Final Report, Vol. 1, Contract 26-2888. (Hopkins, MI)
Swanson DH, Helvig TN (1974) Extended high-altitude retardant drop mechanization study. Honeywell Inc., Government and Aeronautical Products Division. Final Report, Contract 26-2888. (Hopkins, MI)
Swanson DH, Luedecke AD, Helvig TN, Parduhn FJ (1975) Development of user guidelines for selected retardant aircraft. Final Report, Contract 26–3332. Honeywell Inc., Government and Aeronautical Products Division. (Hopkins, MI)
Swanson DH, Luedecke AD, Helvig TN, Parduhn FJ (1977) Supplement to development of user guidelines for selected retardant aircraft. Honeywell Inc., Government and Aeronautical Products Division, Final Report, Contract 26-3332. (Hopkins, MI)
Swanson DH, Luedecke AD, Helvig TN (1978) Experimental tank and gating system (ETAGS). Honeywell Inc., Government and Aeronautical Products Division, Final Report, Contract 26-3425. (Hopkins, MI)
Teske ME, Bird SL, Esterly DM, Ray SL, Perry SG (1997) A user’s guide for AgDRIFT 1.0: a tiered approach for the assessment of spray drift of pesticides. Continuum Dynamics, Inc., Technical Note 95-10. (Princeton, NJ)
Teske ME, Kaufman AE, Johnson GM (1999) Collapsing bucket drop test data with a Lagrangian model. In ‘Proceedings of the 12th Annual Conference on Liquid Atomization and Spray Systems (ICLASS)’, May 1999, Indianapolis, IN. (Institute for Liquid Atomization and Spray Systems (ILASS): Irvine, CA)
Tomé M (2004) Modelação da nuvem de retardante químico: optimização no combate aos fogos florestais. PhD dissertation, University of Aveiro, Portugal.
Tomé M, Borrego C (2002) Fighting wildfires with retardants applied with airplanes. In ‘Proceedings of the 4th International Conference on Forest Fire Research’, 18–23 November 2002, Luso, Coimbra, Portugal. (Ed. DX Viegas) (CD-ROM) (Millpress: Rotterdam)
US EPA (2004) User’s guide for the AERMOD meteorological pre-processor (AERMET) – Revised draft. US Environmental Protection Agency (US EPA), Office of Air Quality Planning and Standards Report EPA-454/B-03-002. (Research Triangle Park, NC)
Westerling AL, Hidalgo HG, Cayan DR, Swetnam TW (2006) Warming and earlier spring increase Western US forest wildfire activity. Science 313, 940–943.
| Warming and earlier spring increase Western US forest wildfire activity.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XotFCitbo%3D&md5=0c50ad3f867d0006079217644781016cCAS | 16825536PubMed |
WHO (2007) ‘The World Health Report 2007 – A Safer Future: Global Public Health Security in the 21st Century.’ (World Health Organization: Geneva)
