Numerical study on 3D nucleate boiling over an oscillating base plate with high wall superheat and multiple nucleation sites

Abstract

This paper is on 3D numerical study on nucleate boiling at high wall superheat of 13.5 K, over an oscillating base plate, using a sharp interface dual-grid level set method (SI-DGLSM)-based in-house code. These studies are performed for two nucleation sites, with two configurations of the computational domain. A micro-layer evaporation model has been used to enable 3D simulations on a coarser grid and higher wall superheats. The size of the computational domain is chosen based on the nucleation site density, reported in experiments, and the present numerical results compare well with the published experimental results; for a stationary horizontal plate under atmospheric pressure. For nucleate boiling on an oscillating plate, bubbles departing from both the nucleation sites synchronize and lock-on with the plate oscillation. Enhancement in heat transfer coefficient is observed in presence of base plate oscillations, which is attributed to increase in rate of phase change as compared to increase in rate of convective heat transfer. Non-uniform distribution of nucleation sites on the base plate leads to formation of local convergence zones on the plate, which in turn affects the motion of bubbles as they rise within the computational domain. The present work is significant as it presents 3D simulations for nucleate boiling under the effect of base plate oscillations—as a promising technique for heat transfer enhancement.

Keywords:

• High heat flux
• inertial frame of reference
• level set method
• nucleate boiling
• oscillating plate

Disclosure statement

No potential conflict of interest was reported by the author(s).