Abstract:
This paper presents a geometric optimisation of conjugate cooling channels in forced convection with
internal heat generation. Two configurations were studied; circular channels and square channels. The
configurations were optimised in such a way that the peak temperatures were minimised subject to
the constraint of fixed total global volume. The fluid was forced through the cooling channels by the pressure
difference across the channels. The structure has one degree of freedom as design variable: channel
hydraulic diameter and once the optimal channel hydraulic diameter is found, optimal elemental volume
and channel-to-channel spacing result. A gradient-based optimisation algorithm is applied in order to
search for the best and optimal geometric configurations that improve thermal performance by minimising
thermal resistance for a wide range of dimensionless pressure difference. This optimiser adequately
handles the numerical objective function obtained from CFD simulations. The results obtained show the
behaviour of the applied pressure difference on the optimised geometry. There are unique optimal design
variables for a given pressure difference. The numerical results obtained are in agreement with the theoretical
formulation using scale analysis and method of intersection of asymptotes.
