This paper was presented at the 4th Micro and Nano Flows Conference (MNF2014), which was held at University College, London, UK. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute, ASME Press, LCN London Centre for Nanotechnology, UCL University College London, UCL Engineering, the International NanoScience Community, www.nanopaprika.eu.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
