One of the main objectives of #HugYourEngine is to shine a spotlight on individuals who are helping make internal combustion engines cleaner and more efficient. This spotlight is on Scott Sluder.
Scott Sluder joined Oak Ridge National Laboratory’s Fuels, Engines, and Emissions Research Center in 1998 and is presently a senior research staff member. Scott has experience in fuel property effects on emissions and combustion, alternative fuels, emissions controls, advanced combustion techniques, and heat exchanger fouling. His work was a critical part of the 2000 EPA ultra-low sulfur diesel rulemaking as well as EPA’s 2010 and 2011 E15 waiver decisions. Scott’s work was on the relationships between NMOG emission and NMHC emissions, resulted in correlations that were adopted into both California LEV III and EPA Tier 3 regulations, and his work on the R factor for fuel economy calculations has been influential in efforts to update the R value used by EPA.
Scott is a member of CRC’s Advanced Vehicles, Fuels, and Vehicles Committee, past vice-chair of SAE’s Engineering Meetings Board and past chair of SAE’s Land & Sea Operating Group. Scott is an SAE Fellow and past winner of SAE’s Forrest R. McFarland and Lloyd L. Withrow Distinguished Speaker Awards. Scott earned his BS and MS in Mechanical Engineering at the University of Tennessee and is a Registered Professional Engineer in the state of Tennessee.
Kelly Senecal (KS): Why did you get started in combustion research?
Scott Sluder (SS): I was inspired by the DOE student vehicle technology competition program while in college and became involved in the program as a student. That exposure to the automotive world “sparked” my interest in the field, leading me first to graduate school and later into my career at ORNL.
KS: What are you working on now?
SS: I’ve worked on a lot of engine, fuel, and emissions-related topics in my career, but most recently I’ve been focused on improving spark-ignition engine efficiency through increasing fuel anti-knock performance.
KS: Describe your lab facilities.
SS: ORNL has been involved in engine research since the mid-1980s, and has developed an extensive array of labs and capabilities to support fuels, engines, and emissions research. I’m an engine researcher, and so I spend most of my time in an engine dynamometer lab that is set up to support multi-cylinder engines, usually those applicable to passenger cars. The engine labs are usually crowded with a breadth of instrumentation. Sometimes it’s hard to find the engine hidden among all the supporting equipment needed to study it!
KS: What’s your favorite type of flame?
SS: Readers who know me will know that I’m more an “applications” engineer rather than someone who is really knowledgeable about “flames.” Having said that, the great majority of the U.S. light-duty fleet is powered by spark-ignited engines that rely on a premixed flame that expands to consume the cylinder charge. So, the near-term opportunities for improving energy use and greenhouse gas emissions in this transportation sector are in improving this robust, time-tested engine design. We may be able to make headway on efficiency improvement through lean-burn technology as well, provided we can solve the associated emissions challenges in a robust, cost-effective manner.
KS: What’s your favorite fuel?
SS: In the spark-ignited fleet, the lowest-risk means of improving efficiency is through improving the anti-knock performance of the fuel to enable engines to use higher compression ratios. The fuels we need to support that pathway include fuels with higher research octane number and octane sensitivity. To simultaneously reduce environmental impact of transportation, we need those fuels to additionally be renewable and/or low-carbon. In at least one recent study that I completed comparing various blendstocks that might help us reach those goals, mid-level ethanol blends proved to be the most effective at boosting octane ratings for a typical petroleum base stock. As a result, they provided the best potential energy efficiency and tailpipe CO2 emissions benefits for a given blend level, although they do not always provide better fuel economy (miles-per-gallon) simultaneously.
KS: What advice would you give students thinking about going into combustion research?
SS: Humans have been burning things for thousands of years, and we still don’t know all there is to know about combustion in terms of making it cleaner and more efficient. It is a challenging and rewarding field and an opportunity to help shape the future of energy use in transportation and power generation. If it’s an area you’re excited about, come join the team!
KS: Is the IC Engine dead?
SS: All the projections that you can find about future powertrains for transportation conclude that the majority of powertrains for at least the next 50 years will include an engine. Many of those engines will be designed to operate as an integral part of a hybridized powertrain. The reason is simple: we still have not found a battery technology that can match the energy-carrying potential of a liquid fuel and simultaneously be both long-lasting and inexpensive. One day that battery might appear; there’s certainly a lot of effort to find that solution. Until it does, though, engines will still be an important part of transportation solutions.
KS: How is your work helping improve fuel efficiency or reduce emissions?
SS: I’ve had the privilege to work on projects that have contributed in a concrete way to the reduction of sulfur in diesel fuel, raised the allowable blend level of ethanol in gasoline to 15%, and reduced the cost of emissions compliance tests for automotive OEMs. I hope that my current focus on improving engine efficiency through increasing fuel anti-knock performance can contribute to the body of work that may lead the nation towards a more efficient, high-octane future.