Flow Field Effects on Flame Kernel Formation in a Spark-Ignition Engine 881639

The effects of mixture turbulence and mean flow velocity on flame kernel formation in a spark-ignition engine were investigated using a disc-shaped optically accessible side chamber.
Three-dimensional flow predictions and LDA measurements were performed to get a better understanding of the flow field in this combustion chamber. Thin wire electrodes were located at a peripheral and a central position introduced into the combustion chamber via the glass windows. High-speed schlieren films at 40 kHz were taken from two orthogonal directions to visualize in detail the formation and development of the flame kernel. The purpose was to gain a better understanding of the interaction of turbulence and flame during the first milliseconds after spark breakdown of a transistorized coil ignition system and a capacitor discharge ignition system.
This study shows that the flame kernel is changed by the turbulence at flame radii of O.5 to 1 mm depending on turbulence intensity. At flame radii of more than 10 mm a fully developed turbulent flame has been formed. The influence of turbulence on the turbulent burning velocity during the flame kernel formation is less than during the main combustion period.


Subscribers can view annotate, and download all of SAE's content. Learn More »


Members save up to 43% off list price.
Login to see discount.
Special Offer: With TechSelect, you decide what SAE Technical Papers you need, when you need them, and how much you want to pay.