An Investigation of Unsteady, In-Cylinder Flows of a Mock-Up Internal Combustion Engine Using Particle Image Velocimetry

Particle Image Velocimetry is frequently used in fluid mechanics and aerodynamics research to provide accurate, quantitative information on the instantaneous structure of a variety of flow fields. This technique provides a nonintrusive means of capturing vital, whole-field details of internal and external flows, such as vortex size and strength, not usually possible through other flow investigation techniques. Due to practical difficulties, the utilization of this method for the study of combustion chamber flow within an internal combustion engine is still relatively uncommon. This study used a TSI Particle Image Velocimetry system to identify two-dimensional flow patterns and velocities on a vertical plane within an optically accessible mock-up combustion chamber including an actuated inlet valve. The data collected served to prove that despite the difficulties inherit in the experimental setup, PIV can be used to obtain useful information relating to two-dimensional internal flows, including unsteady combustion chamber flows. Adjustable parameters within the TSI software allow for instantaneous data to be collected and studied with the inlet valve at any position during the intake process. This type of study will be highly beneficial to the future development of engine head and intake valve design to improve internal combustion engine efficiency and performance.