  Numerical simulation of convective heat transfer over a stationary and
transversely oscillating partial super-hydrophobic cylinder has been performed
using OpenFOAM libraries. Superhydrophobicity of the cylinder surface has been
addressed by means of a partial slip boundary condition. Applying the slip
condition to the surface of the stationary cylinder causes the drag and the rms
lift coefficients to reduce by 46 and 75 percent, respectively. It also
augments the average Nusselt number by 55 percent accompanied by a 21 percent
increase of the natural shedding frequency. The partially superhydrophobic
cylinder has also been investigated and the effects of slip on different
sections of the cylinder surface have been analyzed. Considering the reduction
of force coefficients, it is shown that the application of slip over a 135
segment of the surface is an optimum case, resulting in a 47 and 85 percent
decrease of the drag and the rms lift coefficients, respectively. However, the
fully superhydrophobic cylinder provides higher heat transfer rates. Regarding
the transversely oscillating cylinder, superhydrophobicity extends the primary
synchronization region, and also exhibits different wake dynamics behavior
compared to the no-slip case. The slip over surfaces also causes the average
Nusselt number to become nearly 6 times greater than the no-slip oscillating
cylinder at the lock-in condition. Further analysis based on thermal
performance index (TPI) proves that a high value of TPI = 6 can be reached for
the superhydrophobic cylinder.
