In the cooling channel or channel heat exchanger design, rib, fin or
baffle turbulators are often employed in order to increase the
convective heat transfer rate leading to the compact heat exchanger
and increasing the efficiency. For decades, rib turbulators have been
applied in high-performance thermal systems due to their high
thermal loads. The cooling or heating air is supplied into the passages
or channels with several ribs to increase the stronger degree of cooling
or heating levels over the smooth wall channel. The use of rib
turbulators completely results in the change of the flow field and
hence the variation of the local convective heat transfer coefficient.
The presence of a transverse rib assists to induce the main stream
separation first, and to generate a recirculation zone ahead of it and
then reattachment over the rib itself. A further separation occurring
after the rib and creating a second recirculation zone behind the rib is
followed by another reattachment at the channel wall. If several ribs
exist and their pitch is sufficiently larger than the rib height, these
flow patterns will reoccur along the channel wall. The use of ribs
increases not only the heat transfer rate both for the increased
turbulence degree and for the effects caused by reattachment but also
substantial the pressure loss. The rib geometry and arrangement in
the channel also alter the flow field resulting in different convective