Computational Simulations of Spray Cooling with Air-Assist Injectors

Abstract

A new computational procedure for simulating air-assist flat sprays with atomization is described and demonstrated for surface cooling applications. This procedure builds upon and utilizes findings from our previous work; particularly the integral form of the conservation equations which are used to derive explicit quadratic formulas for drop size. These formulations relate the local energetic state to initial drop size produced by primary atomization processes. In this manner, the local liquid and gas phase velocities prior to atomization are used in the quadratic formula to provide the initial drop size and the appropriate local velocities are utilized as the initial droplet momentum state in a discrete particle tracking algorithm. This procedure has been performed and compared to experimental data for drop size and velocity. This furnishes a platform to further study the effects of droplet distributions on heat transfer and momentum transfer between the spray and a heated metal surface. This approach is based on the conservation principles and generalizable, so that it can easily be implemented in any spray geometry for accurate and efficient computations of two-phase flows including spray cooling.

Acknowledgements

This work was supported in part by the Ministry of Education (Czech Republic), under the program INTER_ EXCELLENCE (project number LTAUSA19053).

Additional information

Notes on contributors

Benjamin Greenlee

Benjamin Greenlee is currently a graduate teaching/research assistant in Mechanical and Aerospace Engineering, SEMTE at Arizona State University, Tempe, AZ. He expects to complete his Ph.D. in 2022. He has published 3 journal papers in spray atomization and computational heat transfer.

Jung-Eun Park

Jung-Eun Park is a Ph.D. candidate in Mechanical and Aerospace Engineering, SEMTE at Arizona State University, Tempe, AZ. She expects to complete her Ph.D. in 2022. She has published 6 journal papers in spray atomization and heat/fluid flows.

Tae-Woo Lee

Tae-Woo Lee is an Associate Professor in the Mechanical and Aerospace Engineering, SEMTE at Arizona State University, Tempe, AZ. His current research interests are in spray flows, heat transfer in sprays, urban environment, and at global scale. In addition to publishing in journals and conferences, he also has written monographs on thermal and flow measurements, and aerospace propulsion.

Hana Bellerova

Hana Bellerova is a research professor in the Laboratory of Heat Transfer and Fluid Flow, Mechanical Engineering at Brno University of Technology. She has a Ph.D. from the same laboratory and has worked at IBM prior to re-joining the lab.

Miroslav Raudensky

Miroslav Raudensky is a Professor and the director of the Laboratory of Heat Transfer and Fluid Flow, Mechanical Engineering at Brno University of Technology. His laboratory has produced extensive data sets on spray heat transfer processes and has unique capabilities to study high mass flux and surface temperature conditions. Aside from spray heat transfer and fluid research, he flies a small aircraft to exotic locations around the world.