  Multiphase flow in parallel channels is often an efficient approach to manage
heat and energy distribution in engineering systems. However, two-phase flow
with heating in parallel channels is prone to maldistribution, resulting in
sub-optimal performance and in some cases, permanent damage. This challenge
requires accurate flow modeling in parallel channels to mitigate or design
against the adverse effect of two-phase flow maldistribution. The nonlinear
nature of multiphase flow results in a multiplicity of predicted solutions for
the same condition, thereby creating significant challenges in modeling flow
distribution. Therefore, this study focuses on solving this challenge by
applying entropy generation analysis and the conservation of mass, momentum
balance, and energy balance to predict two-phase flow distribution in a
two-parallel-channel assembly with a numerical model. Both model predictions
and experimental data show that equally distributed flow becomes severely
maldistributed with a decrease in flow rate, resulting in significant change
(>30%) in the entropy generation rate. We show that the entropy analysis can be
applied in distinguishing between stable and unstable flow distribution, like
the linear stability analysis used in previous studies. We also surpass the
limit of applying linear stability analysis by using entropy analysis to
identify the most feasible end state in a maldistribution process.
