| The motivation of this experiment was to determine if exciting the flow in an internal combustion engine geometry could have positive effects on the developing large structures. The intent being a new method to improve the combustion process in internal combustion engine applications, by controlling the in-cylinder flow characteristics. The experiment used a water analog model of an internal combustion engine, and the focus of the study was on the intake stroke. The shear layer formed by the flow entering through the intake valve was perturbed by applying a disturbance about the nominal position of the intake valve. Sinusoidal disturbances with peak to peak amplitudes of 0.35 mm and 1.00 mm and frequencies incrementing by 10 Hz from 10 Hz to 90 Hz were used to excite the flow through various ranges of the intake stroke. The effects of these disturbances on the flow were first examined with flow visualization techniques, and then velocity fields were measured using Molecular Tagging Velocimetry (MTV).; The data, in the tumble plane, showed significant changes in the large scale flow structures. The MTV results of mean circulation and mean kinetic energy indicate up to a 40% increase in mean circulation, and a 30% increase in mean kinetic energy. |
