Unified Modeling Suite for Two-Phase Flow, Convective Boiling, and Condensation in Macro- and Microchannels

Abstract

The present paper focuses on the unified modeling suite for annular flow that the authors have and continue to develop. Annular flow is of fundamental importance to the thermal design and simulation of microevaporators and micro-condensers for compact two-phase cooling systems of high heat flux components for the thermal management of computer chips, power electronics, laser diodes and high energy physics particle detectors. First, the unified suite of methods is presented, illustrating in particular the most recent updates. Then, results for convective evaporation of refrigerants in non-circular multi-microchannel configurations for microelectronics cooling are presented and discussed. The annular flow suite includes models to predict the void fraction, the entrained liquid fraction, the wall shear stress and pressure gradient, and a turbulence model for momentum and heat transport inside the annular liquid film. The turbulence model, in particular, allows prediction of the local average liquid film thicknesses and the local heat transfer coefficients during convective evaporation and condensation. The benefit of a unified modeling suite is that all the included prediction methods are consistently formulated and are proven to work well together, and provide a platform for continued advancement based on the other models in the suite.

Fundamental issues, mechanisms and models of flow boiling heat transfer in microscale channels

“…Cioncolini [107]. The three-zone heat transfer models and a flow pattern based heat transfer model the three zone model and the annular flow model were evaluated with the database.…”

“…Fig. 29(a) Comparison of the whole R134a heat transfer coefficient data to the flow pattern based model combining the three zone heat transfer model [87] with the unified annular flow heat transfer model [106,107]. Fig.…”

“…Several flow pattern-based mechanistic models for two phase flow and heat transfer in microscale channels have been developed over the past decades [87,[105][106][107]. In particular,…”

On the Phenomenal Mechanisms and Prediction Methods of Flow Boiling Heat Transfer in Microchannels

“…In particular, various new mechanistic models for flow boiling in microscale channels such as three zone heat transfer model for elongated bubbles in microchannels by Thome et al [42,43], recent updated version of three zone model by Costa-Patry and Thome [48] and annular flow heat transfer models covering both macro-and microchannel by Cioncolini and Thome [49] and Thome and Cioncolini [50]. The three-zone heat transfer models and a flow pattern based heat transfer model the three zone model and the annular flow model were evaluated with the database.…”

Pressure drop prediction in annular two-phase flow in macroscale tubes and channels

“…As will be shown, this new improved annular flow pressure drop prediction method is physically sound, is very simple to implement and use, and is superior in accuracy to existing pressure drop correlations. This new pressure drop prediction method is part of the unified annular flow modeling suite that is currently being developed by the authors (Cioncolini et al, 2009a(Cioncolini et al, , 2009bCioncolini and Thome, 2010, 2011, 2012a, 2012bMauro et al, 2014;Thome and Cioncolini, 2016). The great advantage of a unified suite of prediction methods is that all the models included are formulated consistently and are proven to work well together, thus providing a framework for analysis, modeling and future development.…”