Building a Better Mouse Trap: Extending the Life of the Internal Combustion Engine – Part 1

Introducing Jetfire

I am an MIT trained Mechanical Engineer / MBA and worked for General Motors for over 30 years, with a large part of that time in Propulsion System (a.k.a., Powertrain) Planning.  I really enjoyed working cross-functionally on the development of new and improved product offerings. As Executive Director of Global Propulsion Planning, I had the honor to work with some of the industry’s best propulsion engineers, some of which included Tom Stephens, Dan Hancock, Sam Winegarden, Jim Lanzon, Larry Nitz, Pierpaolo Antonioli, and Dan Nicholson. I learned a lot from them, and the experience taught me a few key things…

1. Understand what problem you are trying to solve,
2. There is always high resistance to adding cost in propulsion system improvements, and
3. If you must add cost, make sure it creates significant customer value, and not solely benefits to the enterprise.

I am currently working as an advisor to Michigan State University Professor Harold Schock, who has a combustion technology based on “Turbulent Jet Ignition” (TJI), which dramatically improves fuel efficiency. The professor has named it “Jetfire”, and that is where this story begins...

Professor Schock was introduced to TJI back in the 80’s by Professor Antoni Oppenheim at UC Berkeley. The concept of TJI, however, has roots back to the USSR, and a Russian engineer named L. A. Gussak who first published his work in 1952, and globally patented it in 1963 – in the middle of the Cold War!. TJI never caught on as it had emissions issues, which Professor Schock says have now been overcome.  

I see TJI as the difference between lighting a campfire with a single match versus a flame thrower (which is something I have witnessed firsthand). In a conventional gasoline engine, there is a spark plug (analogous to the “single match”) that ignites the air/fuel mixture (ie, the campfire) in the cylinder. With TJI, there is a “pre-chamber“ where an air/fuel mixture is ignited by a spark plug. This creates flames which are released into the main chamber (ie, the campfire) through tiny holes (making the flame thrower). The result is faster and more robust ignition. 

TJI is used in Formula 1 today. To quote Mike Magda of EngineLabs “It’s basically the most advanced evolution of ignition since the basic spark plug was invented over a century ago”. Mahle markets a system under the MAHLE Jet Ignition? brand and claims it “facilitates the implementation of ultra lean-burn operation in gasoline engines, improving their efficiency and reducing the formation of pollutants such as nitrogen oxide and particulates.”

Professor Schock’s system, however, is unique (and patented) in that it includes dedicated pre-chamber air injection that extends the useful operating range. The technical name for this is “Dual Mode-TJI”, but as mentioned earlier, Professor Schock calls it Jetfire, and has purchased the rights to the name. Jetfire’s big win is stable combustion of highly dilute stochiometric mixtures (confirmed up to 40% EGR with an indicated thermal efficiency of 42%). 

It is exciting to be involved in this type of innovation and help market it to prospective users. I will share more on this amazing technology in a subsequent post. In the meantime, please feel free to contact me directly with any questions at [email protected].