عنوان مجله
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PROGRESS IN NUCLEAR ENERGY
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چکیده
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The main goal of the present work is to investigating the effect of non-uniform axial magnetic field with
positive and negative gradients on subcooled nanofluid flow boiling. Also, for better understanding the
existing phenomena, single-phase convection has been studied in the first part. Control volume technique
for discretizing the governing equations, SIMPLEC algorithm for pressure-velocity coupling, and
SST k-u model for turbulent flow have been used in this research, respectively. In the second part, a three
dimensional two-fluid model is used to subcooled flow boiling and the available R-113 boiling experimental
data are used to validate the results. The obtained results indicate that single-phase convection as
well as subcooled flow boiling characteristics change not only by using nanofluid as a working fluid, but
also by applying the non-uniform axial magnetic field. For the case of magnetic field with negative
gradient, single-phase convection heat transfer rate increases. Also for the subcooled boiling flow,
negative magnetic field gradient will lead to increase critical heat flux (CHF), due to the decrease in
evaporation rate in the wall surface which is eventually responsible for wall dryout. As a result, a more
safe operation condition of the industrial equipments can be achieved.
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