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Cummins, Tula Technology Team Up to Reduce Emissions
Cummins Inc. and Tula Technology, Inc. will collaborate on a technical demonstration of diesel Dynamic Skip Fire (dDSF), which controls cylinder deactivation to reduce emissions and fuel consumption.

Cummins Inc. and Tula Technology used a Cummins X15 Efficiency Series 6-cylinder diesel engine and modified it to incorporate Tula’s Dynamic Skip Fire to reduce emissions and fuel consumption.
Photo: Cummins
Cummins Inc. and Tula Technology, Inc. will collaborate on a technical demonstration of diesel Dynamic Skip Fire (dDSF), which controls cylinder deactivation to reduce emissions and fuel consumption.
Started in early 2019, the goal of this project was to optimize cylinder deactivation strategies for diesel engines to address the upcoming, more stringent NOx regulations.
“We will continue to innovate the diesel engine system to make it lighter, more reliable, powerful and fuel-efficient, and we are encouraged by the progress demonstrated in this collaboration and what it could mean for future diesel technology,” said Lisa Farrell, director of advanced system integration at Cummins.
The team used a Cummins X15 Efficiency Series 6-cylinder diesel engine and modified it to incorporate Tula’s Dynamic Skip Fire to control combustion and deactivation on a cylinder event basis. Even with the low-load cycle being proposed by the California Air Resources Board, the modeling of dDSF technology predicted reductions in NOx emissions and CO2.
“Demonstrating the capability to improve fuel efficiency while also achieving very effective emissions control is extremely important for all diesel engine applications in the future,” said R. Scott Bailey, president and CEO of Tula Technology.
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