Airflow Visualization and LDV Measurements in a Motored Rotary Engine Assembly Part 2: LDV Measurements

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. The compression stroke flow pattern was characterized by a rotor driven flow, although flow reversals were present. All measurements presented in this study were found to be consistent with the flow visualization study reported in [1]*