The flow physics of coaxial sprays have been studied extensively due to the fundamental nature of the interactions between the liquid and gas phases and their many applications. The feedback control of sprays requires an intimate understanding of the physics that determine atomization, as well as those that are responsible for the transport of small liquid drops in a turbulent gas jet. We will review recent experiments where the behaviour of liquid atomization by a high speed coaxial jet has been measured, and the resulting spray (population of droplets, radial concentration and velocities) has been characterized. The detailed interactions of droplets with the background turbulent jet and their effect on the spray distribution will be discussed.
We will then explore different actuation mechanisms to shape the spray to a desired state, that may depend on the application, and show experimental implementations of different multiphysics approaches to control, including electrostatic forcing, acoustic field and flow/swirl pulsation.
About the speaker:
Dr. Aliseda is the PACCAR Professor at the University of Washington in Seattle, WA, USA, where he has been in the faculty since 2006. Since July 2021, he is the Chair of the Department of Mechanical Engineering. He also holds adjunct (courtesy) appointments in Aeronautics and Astronautics and Neurological Surgery. Prior to the UW, he obtained his PhD and did postdoctoral research at the University of California, San Diego. Before his graduate studies at UCSD, he earned a B.Sc./M.Sc. in Aerospace Engineering from the Polytechnic University of Madrid, in 1998. His current interests focus on turbulent and multiphase flows, including flows of interest to energy conversion and environmental problems, such as liquid atomization and cloud microphysics. He also works on biomedical flows, with a special emphasis on the biomechanical basis of cardiovascular disease and the interaction of medical devices with flows in the heart and arteries. He has been a Visiting Professor at the Universidad Carlos 3 de Madrid, the École Normale Supérieure de Lyon and the Laboratoire des Ecoulements Geophysiques et Industriels (LEGI) of the Université Grenoble-Alpes and the École des Mines de Saint-Étienne.