Fire Protection Engineering Department PhD Defense
Nathaniel G. Sauer
Zoom link: https://wpi.zoom.us/j/5526108052
Refreshments will be served – RSVP to firstname.lastname@example.org
Burning Behavior of Fuel on Water Under the Influence of Waves
Prof. Ali Rangwala, Advisor–Professor, Department of Fire Protection Engineering Worcester Polytechnic Institute
Prof. Morris Flynn – Professor, Department of Mechanical Engineering University of Alberta
Prof. Jose Torero – Professor and Head of Civil, Environmental, Geomatic & Environmental Engineering, University College London
Leonard Zabilansky, PE – Principal Engineer
National Oil Spill Response Research & Renewable Energy Test Facility
Prof. Albert Simeoni – Professor and Department Head, Fire Protection Engineering Worcester Polytechnic Institute
A quick and effective response is critical to minimizing environmental damage resulting from oil spills at sea. In-situ burning (ISB) is a cleanup and containment method that calls for the gathering and burning of spilled fuel in place on the ocean surface. ISB is a frequently used tool for oil-spill mitigation, during the 2010 Deepwater Horizon spill over 400 burns were conducted which removed approximately 250,000 gallons of oil from the environment. ISB is particularly well
regarded for its speed, effectiveness, and low cost. All fire research to this date has focused on the burning of fuel on a stagnant water sublayer, which is not a realistic boundary condition comparable to what happens in oceans and rivers where the water surface is wavy. This work fills this critical knowledge gap by asking what happens when the water sublayer is wavy. Secondly, it also resolves the water movement imposed by the wave into an equivalent heat transfer convective boundary condition. This boundary condition is then used to solve the burning rate of fuel.
A wave generally has a negative effect on burning by decreasing the burning rate, lowering internal fuel temperatures, and increasing unburnt residues, primarily through an increase in heat loss to the water. To fully understand the nature of this heat loss, the wave's fluid mechanics and heat transfer aspects were analyzed by conducting experiments in three wave tanks capable of sustaining pool fires of 0.1 m, 1 m, and 2 m in diameter. The investigations revealed a strong dependence on the burning rate of the fuel layer with a nondimensional parameter defined as wave steepness equal to the ratio of wave height to wavelength. The experiments show that increasing steepness increases the heat transfer rate at the oil-water interface, reducing the burning rate. Results are also modeled using a 1-D heat transfer model, where heat loss to the wavy water is analyzed by an experimentally determined convective heat transfer coefficient.
Nate joined the Department of Fire Protection Engineering Ph.D. program in January 2019, working under Professor Ali S. Rangwala as a researcher in the Combustion Laboratory. His work has primarily focused on pool fire burning behavior, emphasizing the improvement of environmental fuel spill cleanup. Nate holds a BS in Mechanical Engineering and an MS in Fire Protection Engineering from Worcester Polytechnic Institute.