Papers presented to the 11th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, South Africa, 20-23 July 2015.
This paper presents a three-dimensional geometric optimisation
of conjugate cooling channels in forced convection with
internal heat generation within the solid. Hexagonal cooling
channels configuration are considered and Al2O3-water
nanofluid is used as cooloing fluid because of its promising
superior thermal properties over traditional cooling fluids
The main objective is to optimise the configuration in such a
way that the peak temperature is minimised subject to the
constraint of fixed global volume of solid material. The cooling
fluid is driven through the channels by the pressure difference
across the channel.The elemental volume of the structure and
hydraulic diameter of the cooling channel were considered as
design variables. Also, different values of volume fraction of
Al2O3 nanoparticles added into water that enhanced the cooling
effect are considered. The shape of the channel is allowed to
morph to determine the best configuration that gives the lowest
peak temperature. A gradient-based mathematic optimisation
algorithm (Dynamic-Q) is applied in order to search for the best
optimal geometric configuration that improves thermal
performance by minimising peak temperature for a wide range
of pressure difference. Results obtained show that there are
unique optimal geometry for a given pressure difference. Also,
the results show that the effects of pressure difference, volume
fraction of Al2O3 nanoparticles on minimum peak temperature
and hydraulic diameter of the channel are consistent with those
obtained in the open literature.
