Characterizing the Atomization of a Liquid Mass

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Canada's commitment to Paris accord can only be realized with a significant reduction in emissions from oil and gas, and transportation sectors. Oil and gas accounts for 26% and transportation for 23% of Canada's total GHG emissions. In North America, combustion of gasoline and diesel fuel make up for 84% of all transportation energy. Therefore, any improvement in combustion energy efficiency, can have a large impact on the total emission. Combustion efficiency and emission intimately relate to the fuel injection and mixing inside the combustion chamber. More and more engines utilize Gasoline Direct Injection (GDI) because of its higher fuel efficiency. In addition, diesel and biodiesel fuels are become more popular, again because of their fuel efficiency. Therefore, further improvements in the fuel efficiency and emission reduction require a better understanding of the fuel injection and atomization processes and development of models to predict these processes. Such models can be implemented in spray combustion codes to modify engine designs, optimize the combustion efficiency, and reduce emissions. ***A novel experiment is proposed that will provide a well-defined characterization of the atomization process. Breakup of an initially stationary (suspended) liquid droplet by a high velocity gas jet will be studied. A systematic study of the breakup of a single droplet allows for the understanding of the effects of both physical and chemical properties of the fuel and injector geometry. Each droplet breakup event generates a certain number of droplets with certain size distribution. If we can model each event, then we will be able to model a liquid atomization process by combining several relevant droplet breakup events. Therefore, a single droplet breakup event will be the basis for our more general atomization model. ***Another goal of the present proposal is to develop a new spray droplet sizing system, so that spray researchers, developers and users can improve their spray nozzles. The proposed system is based on the traditional imaging method, however, it utilizes a novel arrangement for the lighting and the camera system with respect to the spray. A nano-second flash LED will be used to freeze the motion of fast moving droplets. This instrument will allow online characterization of a spray in an industrial setting, which can help all spray users improve system efficiency, reduce fuel consumption, and enhance fuel delivery. The proposed system will cost 20 times less than the currently available systems for spray sizing. An innovation than provides an order of magnitude improvement (10 times) in the existing system, is considered a disruptive innovation. Considering that sprays are used in a broad range of industries, we believe that the proposed device is truly a disruptive innovation.