Funding to Assist with Engine Knock Research
If you were to do an internet search for what causes engine knock, you’d receive a number of answers. Ramanan Sankaran—a scientific computing specialist at the Oak Ridge Leadership Computing Facility (OLCF), a Department of Energy Office of Science User Facility located at Oak Ridge National Laboratory, and joint faculty member at the University of Tennessee—wants to take Titan through the fuel lines to help identify the right one.
Through funding from the King Abdullah University of Science and Technology (KAUST), Sankaran will be working with two researchers from the KAUST Clean Combustion Research Center, Hong G. Im and Bok Jik Lee. Located along the Red Sea in Thuwal, Saudi Arabia, the center’s main mission is to conduct leading combustion research to tackle future energy and environmental challenges. The facility opened earlier this year.
Based at the OLCF, Sankaran will be working in collaboration with the center in the development of high-fidelity numerical tools for combustion research and applying them in some high-impact numerical simulations. In short, Sankaran and the team plan to develop code to run simulations on Titan to help determine what causes engine knock. Titan, a Cray XK7 supercomputer, is the nation’s fastest supercomputer.
Engine knock occurs when the combustion of the air–fuel mixture in an engine explodes at the wrong point in the sequence. “This improper detonation, as opposed to smoother combustion, is problematic,” Sankaran said. “We want to develop better diagnostics for the cause of those improper detonations.”
Their high-fidelity simulations will help determine how engine knock develops and assist in predicting how the transition from smooth combustion to knocking occurs. The danger with engine knock, Sankaran explains, is that it can damage the engine components.
To get to the root of the problem, he has outlined a number of steps in the research project. First, the team will put together the simulation tool suite and develop the necessary code to run on high-performance computing systems like Titan. Then the researchers will begin the simulations to try to diagnose where the proper fuel mixture goes awry, leading to engine knock.“We are hoping the simulations will be able to accurately predict the transition to engine knock after the onset of the smoothly propagating combustion in the fuel mixture. We will investigate what conditions lead to engine knock and then, after gaining that improved understanding, we will be able to know when to expect engine knock,” Sankaran said.
The initial phase of the research is projected to last around a year. “A year from now,” he said, “we hope to have performed our first simulations.”
A second phase, focusing on improving fuel efficiency and reducing emissions, should follow shortly thereafter.