William (Ruddy) E. Mell
Research Combustion Engineer
400 N 34th St., Suite 201
Contact William (Ruddy) E. Mell
I develop a range of fire behavior models with varying emphasis on physics-based submodels (spanning laboratory to landscape spatial scales) through vegetative fuels (both surface and crown) and the mixture of vegetation and structural fuels comprising the wildland-urban interface. In my work, I collaborate with experimentalists to design and conduct experiments to aid model development and validation. I also use present-day ground-based and aerial technologies to measure fine-scale characteristics of fuels and fire behavior across landscapes and I evaluate new and existing fire behavior models using well- constructed fuel, fire behavior, and smoke databases.
Large eddy simulation methods (LES); numerical combustion; computational fluid dynamics (CFD); effects of physics in fires on vegetation, structures, and the wildland-urban interface; measurement and simulation of wind over complex terrain; thermal radiation modeling; multimaterial simulation of fluid structure interaction processes; laboratory and field measurements of fire behavior, vegetation, and wind; remote sensing measurements of fuels, fire behavior, and smoke.In previous work, I developed efficient two- and three-dimensional high-resolution, problem-dependent thermal radiation solvers for large eddy simulations of fires, including both multigrid and direct solvers; extended microgravity combustion code to include the effects of thermal radiation on the transition from ignition to flame spread; and incorporated flame spread submodels developed by coworkers into a large eddy simulation code to simulate the burning of commodity synthetic materials in a laboratory environment (cone calorimeter).
In previous work, I developed efficient two- and three-dimensional high-resolution, problem-dependent thermal radiation solvers for large eddy simulations of fires, including both multigrid and direct solvers; extended microgravity combustion code to include the effects of thermal radiation on the transition from ignition to flame spread; and incorporated flame spread submodels developed by coworkers into a large eddy simulation code to simulate the burning of commodity synthetic materials in a laboratory environment (cone calorimeter).
Why This Research is Important
The foundation for current fire behavior models in the U.S. Forest Service was constructed in the 1970s. Given the computational resources at the time, this foundation is heavily based on empirical results from laboratory-scale experiments. Affordable computational resources (including cloud computing) and numerical methods for combustion and wind flow have advanced tremendously since the early 1970s. Thus, the stage is set for a renewed evaluation and improvement of the existing models and development of new, more complete physics-based models. This will provide a more complete and robust set of fire behavior modeling tools to meet current challenges, including the wildland-urban interface (risk assessment and mitigation), effective fuel treatments, prescribed fire (fire effects, smoke generation, and transport), and firefighter safety.
- University of Washington, Ph.D. Applied Mathematics 1994
- University of Washington, M.S. Applied Mathematics 1987
- University of Minnesota, B.S. Geophysics 1981
- Combustion Engineer, Pacific Wildland Fire Sciences Lab
2011 - Current
Modeling and measurement of physical processess in wildland and wildland-urban interface fires. Objectives are to advance fire behavior and smoke modeling. These models will support fire managers, forest resource managers, air quality regulaors, smoke modelers, and wildland-urban interface communities.
- Research Scientist, National Institute of Standards and TecnologyBuilding and Fire Research Laboraotry (now subsumed in Engineering Laboratory)
2004 - 2011
Co-Program leader of Wildland-Urban Interface Fire program which included experimental and field measurements and computer model development.
- Research Professor, University of Utah
1999 - 2004
Staff member of the Center for the Simulation of Accidental Fires and Explosions. Developed simulation approaches for microgravity combustion and wildland fires.
- Research Scientist, National Institute of Standards and TechnologyBuilding and Fire Research Lab
1996 - 1999
NIST research staff. Developed, implemented, and tested models for combustion, radiation heat transfer, and flame spread.
- National Research Council Associate, National Institute of Standards and Technology
1994 - 1996
Two year postdoc position at NIST focus on fire modeling.
- International Association of Wildland Fire, Associate Editor (2009 - Current)
Awards & Recognition
- Sjolin Award for International Forum of Fire Research Directors, 2012
Recognizes and outstanding contribution to the science of fire safety or an advance in the state of the art in fire safety engineering practice of extraordinary significance.
- USDA Forest Service, Pacific Northwest Station Director's Award, 2012
- NIST Engineering Laboratory's Communicator Award, 2009
Awarded by the laboratory for excellence in communicating ongoing laboratory sponsored research. Awarded for the project leading to the publication: "Numerical simulation and experiments of burning Douglas fir trees".
- Harry C. Bigglestone Award, 2001
International award sponsored by the Fire Protection Research Foundation. Honors most outstanding paper published in Fire Technology. Awarded for paper entitled: "A heat transfer model for fire fighters' protective clothing".
- Presidential Early Career Award for Scientists and Engineers (PECASE), 2001
Highest honor bestowed by the United States government on outstanding scientists and engineers in the early stages of their independent research careers. Awarded by NASA for work on the simulation of g-jitter effects on combustion processes.
- National Research Council Postdoctoral Research Associateship, 1994
Two year postdoc at the National Institute of Standards and Technology's Building and Fire Research Laboratory
- Vanella, Marcos ; McGrattan, Kevin ; McDermott, Randall ; Forney, Glenn ; Mell, William ; Gissi, Emanuele ; Fiorucci, Paolo . 2021. A multi-fidelity framework for wildland fire behavior simulations over complex terrain.
- Ziegler, Justin P.; Hoffman, Chad M.; Collins, Brandon M.; Knapp, Eric E.; Mell, William (Ruddy). 2021. Pyric tree spatial patterning interactions in historical and contemporary mixed conifer forests, California, USA.
- Mueller, Eric V; Skowronski, Nicholas S.; Clark, Kenneth L.; Gallagher, Michael R.; Mell, William E.; Simeoni, Albert ; Hadden, Rory M. 2020. Detailed physical modeling of wildland fire dynamics at field scale - An experimentally informed evaluation.
- Ritter, Scott M.; Hoffman, Chad M.; Battaglia, Mike A.; Stevens-Rumann, Camille S.; Mell, William E. 2020. Fine-scale fire patterns mediate forest structure in frequent-fire ecosystems.
- Ziegler, Justin P.; Hoffman, Chad M.; Collins, Brandon M.; Long, Jonathan W.; Dagley, Christa M.; Mell, William . 2020. Simulated fire behavior and fine-scale forest structure following conifer removal in aspen-conifer forests in the Lake Tahoe Basin, USA.
- Dietenberger, Mark A.; Boardman, Charles R.; Shotorban, Babak ; Mell, William ; Weise, David R. 2020. Thermal degradation modeling of live vegetation for fire dynamic simulator.
- Morandini, F. ; Santoni, P.A. ; Tramoni, J.B. ; Mell, W.E. . 2019. Experimental investigation of flammability and numerical study of combustion of shrub of rockrose under severe drought conditions.
- Liu, Yongqiang ; Kochanski, Adam ; Baker, Kirk R.; Mell, William ; Linn, Rodman ; Paugam, Ronan ; Mandel, Jan ; Fournier, Aime ; Jenkins, Mary Ann; Goodrick, Scott ; Achtemeier, Gary ; Zhao, Fengjun ; Ottmar, Roger ; French, Nancy H. F.; Larkin, Narasimhan ; Brown, Timothy ; Hudak, Andrew ; Dickinson, Matthew ; Potter, Brian ; Clements, Craig ; Urbanski, Shawn ; Prichard, Susan ; Watts, Adam ; McNamara, Derek . 2019. Fire behaviour and smoke modelling: model improvement and measurement needs for next-generation smoke research and forecasting systems.
- Ziegler, Justin P.; Hoffman, Chad M.; Battaglia, Mike A.; Mell, William . 2019. Stem-maps of forest restoration cuttings in Pinus ponderosa-dominated forests in the interior West, USA.
- Prichard, Susan ; Larkin, Sim N.; Ottmar, Roger ; French, Nancy H.F.; Baker, Kirk ; Brown, Tim ; Clements, Craig ; Dickinson, Matt ; Hudak, Andrew ; Kochanski, Adam ; Linn, Rod ; Liu, Yongqiang ; Potter, Brian ; Mell, William ; Tanzer, Danielle ; Urbanski, Shawn ; Watts, Adam . 2019. The fire and smoke model evaluation experiment a plan for integrated, large fire atmosphere field campaigns.
- Weise, David R.; Fletcher, Thomas H.; Johnson, Timothy J.; Hao, WeiMin ; Dietenberger, Mark ; Princevac, Marko ; Butler, Bret ; McAllister, Sara ; O’Brien, Joseph ; Loudermilk, Louise ; Ottmar, Roger ; Hudak, Andrew ; Kato, Akira ; Shotorban, Babak ; Mahalingam, Shankar ; Mell, William E. 2018. A project to measure and model pyrolysis to improve prediction of prescribed fire behavior.
- Hoffman, Chad M.; Sieg, Carolyn H.; Linn, Rodman R.; Mell, William ; Parsons, Russell A.; Ziegler, Justin P.; Hiers, J. Kevin. 2018. Advancing the science of wildland fire dynamics using process-based models.
- Mueller, Eric V; Skowronski, Nicholas ; Thomas, Jan C.; Clark, Kenneth ; Gallagher, Michael R.; Hadden, Rory ; Mell, William ; Simeoni, Albert . 2018. Local measurements of wildland fire dynamics in a field-scale experiment.
- Parsons, Russell A.; Pimont, Francois ; Wells, Lucas ; Cohn, Greg ; Jolly, W. Matt; de Coligny, Francois ; Rigolot, Eric ; Dupuy, Jean-Luc ; Mell, William ; Linn, Rodman R. 2018. Modeling thinning effects on fire behavior with STANDFIRE.
- Perez-Ramirez, Y. ; Mell, William E.; Santoni, P. A.; Tramoni, J. B.; Bosseur, F. . 2017. Examination of WFDS in modeling spreading fires in a furniture calorimeter.
- Thomas, Jan C.; Mueller, Eric V.; Santamaria, Simon; Gallagher, Michael; El Houssami, Mohamad; Filkov, Alexander; Clark, Kenneth; Skowronski, Nicholas; Hadden, Rory M.; Mell, William; Simeoni, Albert. 2017. Investigation of firebrand generation from an experimental fire: Development of a reliable data collection methodology.
- Filho, Guenther Carlos Krieger; Bufacchi, Paulo ; Santos, José Carlos; Veras, Carlos Alberto Gurgel; Alvarado, Ernesto C.; Mell, William ; Carvalho, João Andrade. 2017. Probability of surface fire spread in Brazilian rainforest fuels from outdoor experimental measurements.
- Ziegler, Justin Paul; Hoffman, Chad; Battaglia, Michael; Mell, William. 2017. Spatially explicit measurements of forest structure and fire behavior following restoration treatments in dry forests.
- Mueller, Eric V.; Skowronski, Nicholas; Clark, Kenneth; Gallagher, Michael; Kremens, Robert; Thomas, Jan C.; El Houssami, Mohamad; Filkov, Alexander; Hadden, Rory M.; Mell, William; Simeoni, Albert. 2017. Utilization of remote sensing techniques for the quantification of fire behavior in two pine stands.
- Bova, Anthony S.; Mell, William E.; Hoffman, Chad M. 2016. A comparison of level set and marker methods for the simulation of wildland fire front propagation.
- Hoffman, C. M.; Ziegler, J.; Canfield, J.; Linn, R. R.; Mell, W.; Sieg, C. H.; Pimont, F. 2015. Evaluating crown fire rate of spread predictions from physics-based models.
- Mueller, Eric; Skowronski, Nicholas; Clark, Kenneth; Kremens, Robert; Gallagher, Michael; Thomas, Jan; El Houssami, Mohamad; Filkod, Alexander; Butler, Bret; Hom, John; Mell, William; Simeoni, Albert. 2015. Initial results from a field experiment to support the assessment of fuel treatment effectiveness in reducing wildfire intensity and spread rate.
- Mueller, Eric; Skowronski, Nicholas; Simeoni, Albert; Clark, Kenneth; Kremens, Robert; Mell, William; Gallagher, Michael; Thomas, Jan; Filkov, Alexander; Houssami, Mohamad El; Hom, John; Butler, Bret. 2014. Fuel treatment effectiveness in reducing fire intensity and spread rate - An experimental overview.
- Mueller, Eric; Mell, William; Simeoni, Albert. 2014. Large eddy simulation of forest canopy flow for wildland fire modeling.
- Morvan, Dominique ; Meradji, Sofiane ; Mell, William . 2013. Interaction between head fire and backfire in grasslands.
- Hoffman, Chad M.; Sieg, Carolyn H.; Morgan, Penelope; Mell, William Ruddy; Linn, Rodman; Stevens-Rumann, Camille; McMillin, Joel; Parsons, Russell; Maffei, Helen. 2013. Progress in understanding bark beetle effects on fire behavior using physics-based models.
- Hoffman, Chad M.; Morgan, Penelope; Mell, William; Parsons, Russell; Strand, Eva; Cook, Steve. 2013. Surface fire intensity influences simulated crown fire behavior in lodgepole pine forests with recent mountain pine beetle-caused tree mortality.
- Maranghides, Alexander; Mell, William. 2012. Framework for addressing the national wildland urban interface fire problem determining fire and ember exposure zones using a WUI hazard scale.
- Michaletz, S.T.; Johnson, E.A.; Mell, W.E.; Greene, D.F. 2012. Timing of fire relative to seed development controls availability of non-serotinous aerial seed banks.
- Parsons, Russell A.; Mell, William E.; McCauley, Peter. 2011. Linking 3D spatial models of fuels and fire: Effects of spatial heterogeneity on fire behavior.
- Morvan, Dominique ; Hoffman, Chad ; Rego, Francisco ; Mell, William . 2011. Numerical simulation of the interaction between two fire fronts in grassland and shrubland.
- Morvan, Dominique; Meradji, Sofiane; Mell, William. 2011. Numerical study of the interaction between a head fire and a backfire propagating in grassland..
- Parsons, Russell A.; Mell, William; McCauley, Peter. 2010. Modeling the spatial distribution of forest crown biomass and effects on fire behavior with FUEL3D and WFDS.
- Hoffman, Chad; Parsons, Russell; Morgan, Penny; Mell, Ruddy. 2010. Numerical simulation of crown fire hazard following bark beetle-caused mortality in lodgepole pine forests.
- Zipperer, Wayne; Long, Alan; Hnton, Brian; Maranghides, Alexander; Mell, William. 2007. Mulch flammability.
- Forney, Glenn P.; Mell, William. 2007. Visualization and modeling of smoke transport over landscape scales.