Research
Current Research
A limitation of current LED lamps is heat transfer; high temperatures over time degrade performance. Most lamp manufacturers have adopted a large aluminum heat sink to address this issue. The heat sink and the upstream manufacturing of the aluminum have been identified as the primary environmental concern for the lamps. This presents a unique opportunity for research that will improve the thermal performance of the LEDs, reduce the size of the heat sinks, demonstrate cutting edge modeling techniques, and educate the lighting industry about thermal design. Undergraduate students are currently leading the experimental testing of existing LED products and thermal calculations.
Natural convection heat transfer has been shown to exhibit characteristics of chaotic mathematical transitions. Proper Orthogonal Decomposition (POD) is one type of reduced order modeling which has many names and has been used to characterize fluid transitions by prior researchers, but has been applied in a limited way to heat transfer systems. Student researchers are currently performing experimental work that will be compared to CFD models and mathematical predictions of these transitions.
Research on energy efficiency is currently focused on big data and heat transfer problems in building science. We are working to understand key characteristics of building performance, including renewable energy systems like thermal solar systems and photovoltaics. Related work is focused on passive cooling, and innovative HVAC methods. Student researchers are building experimental systems and evaluating data collected.
Prior Research
Diesel emissions and aftertreatment
Research at PNNL focused on the modeling and experimental work related to diesel emissions. Key contributions include technical leadership for laboratory data acquisition systems and innovative approaches to modeling. Supported the team which developed the after-treatment system for the Audi R10 TDI which won Le Mans in 2006.
Thermodynamic properties of ethanol
Research at the Center for Applied Thermodynamics Studies at the University of Idaho focused on thermodynamics. The research team developed a Helmholtz equation of state for the fluid ethanol. The development included a least squares regression to reduce experimental data. The result is the most accurate thermodynamic model for ethanol available, and has been included in industry standard thermodynamic analysis software. Related studies included exergy analysis and the combustion behavior of water-ethanol fuel mixtures.