NetJets is pleased to be working with the engineers and scientists at Princeton to develop new jet fuels with near-zero net greenhouse gas emissions. Princeton has a longstanding history of leadership in aerospace science. We feel they will make great strides with this research.

—Richard Santulli

The NetJets-funded research project provides the opportunity to make substantial progress toward the launching of green technologies not only for corporate jets, but also for commercial aviation and transportation in general, according to Robert Williams, a senior research scientist at the Princeton Environmental Institute and member of the NetJets-sponsored research team. Professor of Mechanical and Aerospace Engineering Fred Dryer will lead the Princeton team, which also includes Associate Professor of Mechanical and Aerospace Engineering Yiguang Ju, and Eric Larson, a research engineer at the Princeton Environmental Institute. In addition, the work will involve collaboration with researchers at the Institute of Transportation Studies at the University of California-Davis.

The Princeton researchers will center their efforts on the synthesis of jet fuels from the gasification of a combination of coal and biomass. A key component of their solution is isolating and storing the carbon dioxide produced during synfuels production.

An especially attractive feature of processing coal and biomass together to make synfuels is that it requires only half the amount of biomaterial as pure biofuel production, while still making fuels with near-zero greenhouse gas emissions, according to Williams.

Air Force Project for Combustion Models. Dryer is also leading a major project funded by the US Air Force to develop computational and kinetic models that accurately simulate the combustion of jet fuel.

The Air Force program is one of the Defense Department’s Multi-disciplinary University Research Initiative (MURI) grants. One of only ten such projects supported by the Air Force this year, the collaboration involves researchers from four institutions:Princeton, Case Western Reserve University, Pennsylvania State University and the University of Illinois-Chicago. The award, with an overall value of up to $7.5 million, will provide support for three years with the option of a two-year extension. Research began in July and the kick-off meeting for the project will be held 17 September in Princeton.

Dryer and his MURI collaborators, including Ju, will develop methods to predict and evaluate how jet fuels will behave in actual engines and characterize the emissions they will produce. While current guidelines specify some overall properties of jet fuels, they do not spell out the actual chemical composition. Depending on the source and processing method, jet fuel typically consists of hundreds to thousands of molecular structures that behave in a variety of ways.

The models developed by the team will represent and characterize the behavior of this broad range of jet fuel species using only a few types of molecular structures as surrogates for the larger whole. Dryer previously developed similar surrogate fuel models to represent gasoline, which are now being used for engine design by the automotive industry.

The rules and methods developed by the research team also will support the future use of alternative jet fuel sources, including liquids derived from coal or biomass, by providing an increased understanding of their combustion properties in comparison to petroleum-derived materials. In order to make alternative jet fuel sources feasible, they need to be compatible with petroleum and produce similar combustion performance. This will only be possible if we fully understand how alternative fuels burn and design engines based on this fundamental knowledge.

—Fred Dryer

According to the US Department of Transportation, aviation is responsible for around 10% of the greenhouse gas emissions from transportation in the nation, or roughly 2.7% of the country’s total greenhouse gas emissions.

In June, the National Aeronautics and Space Administration (NASA) selected Reaction Design to develop fuel models for simulating the operation of jet engines with alternative fuels. The two-year project will be led by Reaction Design with experimental support from researchers at the University of Southern California. (Earlier post.)

Resources:

• EU ETS: The Case of Business and General Aviation (NetJets)

• Workshop on Combustion Simulation Databases for Real Transportation Fuels (NIST 2003)

• DOD/AF Assured Fuels Initiative Update) (July 2007