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William (Ruddy) E. Mell

William (Ruddy) E. Mell
Research Combustion Engineer
Threat Characterization and Management
400 N 34th St., Suite 201
Seattle, WA 98103-8600
United States
Phone
206-732-7868
Email
Current Research
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.
Past Research

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).

Research Interest

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).

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.
Education
  • University of Washington, Ph.D., Applied Mathematics, 1994
  • University of Washington, M.S., Applied Mathematics, 1987
  • University of Minnesota, B.S., Geophysics, 1981
Professional Experience
  • 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.
Professional Organizations
  • Associate Editor,  International Association of Wildland Fire,  2009 - Current
    Associate editor
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
Other Publications
https://www.fs.usda.gov/research/about/people/wemell