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Indexed by:期刊论文

Date of Publication:2018-01-01

Journal:INTERNATIONAL JOURNAL OF NUMERICAL METHODS FOR HEAT & FLUID FLOW

Included Journals:SCIE

Volume:28

Issue:10

Page Number:2442-2462

ISSN No.:0961-5539

Key Words:Phase change; Lattice Boltzmann method; Droplet; Falling; Freezing trend

Abstract:Purpose The freezing phenomenon of a falling droplet is a frequently encountered phenomenon in various applications, such as spray crystallization, hail formation and artificial snowmaking. Therefore, this paper aims to understand the freezing processes of a falling droplet without and with initial horizontal velocity in a cold space.
   Design/methodology/approach The freezing processes of a falling droplet were characterized using a modified enthalpy-based lattice Boltzmann method.
   Findings The temperature field, streamlines and freezing process of the falling droplet were investigated and analyzed. The lower part of the droplet was frozen earlier than the upper part. The freezing trend slowed down in the later stage of the freezing process. The droplet shape was related to the initial vertical velocity, nucleation temperature and initial horizontal velocity.
   Originality/value A modified enthalpy-based lattice Boltzmann method is proposed. In the model, the improved pseudo-potential model is used and the radiation is considered. This method was firstly used to simulate the freezing process of a falling droplet. By examining these freezing processes in detail, the freezing trend and the effect factors of droplet deformation and freezing time were obtained, respectively.