“If you make an engine in the United States, chances are you use our software,” said Kelly Senecal, cofounder of Convergent Science, referring to its flagship CONVERGE software for advanced engine simulation. In fact, the software reaches well beyond where it was created in the University of Wisconsin-Madison, with engine manufacturers in the United States, Japan and Europe starting to make the switch as well.
So what is it about CONVERGE that's so appealing? The software is capable of predicting and explaining events within the cylinder of an internal combustion engine, which means it's useful to analyze virtually any type of engine powered by gasoline or diesel fuel. It works by combining computational fluid dynamics (CFD), the analysis of the movement of liquids and gases, with engine design software.
“CFD had been used for simulation,” Senecal said. “They would run a case and see what they could learn from it, but there was no way to incorporate the improvement into the design process automatically.” CONVERGE addresses that drawback.
Engine Engineering the Smart Way
CONVERGE uses an approach borrowed from evolutionary science. A “genetic” process tests incremental changes in engine design and looks to their outcome to evaluate which changes yield the best results. These changes are then implemented and the process begins again. “You have these criteria related to power, efficiency and/or emissions that you use to evaluate the design as it evolves, generation after generation, based on the principles of evolution through natural selection,” said Senecal.
- No user meshing: The software automatically generates the grid at runtime.
- Adaptive mesh refinement (AMR): AMR adjusts the resolution of certain parts of the grid automatically based on user specifications.
- Combustion simulation: CONVERGE includes several advanced models for simulating combustion.
As Senecal noted, design engineers using the software will be able to find answers to questions that previously required costly trial and error to address: “What is the best timing for the fuel injection? When should the spark happen? How do you inject fuel relative to the shape of the head, piston, valves and ports? All of these questions can be answered with modeling, and that's a lot cheaper than shaping metal and testing every design.”
Since fluid dynamics can also be applied to describe events inside jet engines, catalytic converters, pumps and compressors, there's a wide range of applications that could benefit from advanced CFD software such as CONVERGE. As Senecal noted, problems combining fluid flow with fast-moving parts “make CFD difficult if your expertise is analyzing fluid flow in a pipe, but it's pretty easy for us.”