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The purpose of this work was to develop a high speed flow visualization system which could be used to observe the behavior of the air flow in a steady flow cylinder head assembly. This type of experimental rig has been used by engineers for many years to evaluate valve discharge coefficients. This study is believed to be the first high speed flow visualization of the air flow in a system of this type. Particular emphasis was placed on the characterization of intake generated swirl and tumble motions within the cylinder. A 40 watt copper vapor laser was used to expose motion picture films at 5000 frames per second. The light scattering medium was phenolic microballoons. Based on the flow visualization results, selected LDV measurements were made to quantify the visual observations. A propylene glycol aerosol was used for seeding in the LDV experiments.

An experimental study of the blowby past the apex seals and its controlling effect on the flow field was conducted in a motored rotary engine. A high speed flow visualization technique and laser Doppler anemometry (LDA) measurements were applied to analyze the blowby past two--piece and three-piece engine apex seals under motored conditions of 2000 rpm crank shaft speed. A light sheet from a 40 watt pulsed copper vapor laser was synchronized with a high speed rotating prism camera to record light scattered off microballoon particles onto motion picture films photographed at 5000 frames per second. A sequence of photographs is selected from the films to demonstrate the blowby characteristics past the apex seals and their effect on the flow field during the intake and compression strokes. Detailed LDA velocity measurements using propylene glycol as seeding particles, 0.6 μm in diameter, are also presented to quantify the blowby past the apex seals.

Laser Doppler velocimetry (LDV) has been used to make ensemble averaged and root mean square (RMS) velocity measurements at a crank shaft speed of 675 rpm in a motored rotary engine assembly. Sapphire windows on both ends of the side housings allowed forward scatter optical access. Measurements were taken during the intake and compression strokes. Also, measurements were made in the major plane (defined by the major axis and the normal to the side housing) near the central housing wall to quantify the blowby that has proven to be a dominating feature in the intake flow pattern. This phenomenon has not been previously reported in the literature and has a major impact on how the Rotary Combustion Engine (RCE) combustion process can be numerically simulated. The intake stroke flow pattern was found to be dominated by a large scale vortical structure circulating in the opposite direction from the rotor motion.