Enigneering Creativity Award: Fluid Mechaical Optimization of Two-Stroke Engines

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The objective of this research in fluid mechanics is to increase the output and fuel economy of an internal combustion (IC) engine by examining the exact flow inside an engine thereby enhancing the mixture of the incoming air and fuel. Better mixing means more complete burning of the fuel which also implies safer emissions. Current techniques involving the fluid mechanics of engine flows are limited particularly in capturing important information regrading fluid turbulence. A new technique has been developed at Michigan State University involving a laser beam which is divided to form a grid of intersecting lines in the engine. With this new technique a wide variety of engine diagnostics and fluid mechanics will be performed. Using the velocity gradient in the region of the grid obtained by the new techniques, the strain rates and vorticity quantities will be determined. Internal engine design would benefit using these quantities since it would be possible to optimize scavenging of the cylinder of burnt gases and minimize mixing with the burnt charge. The new technique offers improved possibilities for pre-combustion mixing of air and fuel.