|
Abstract: Fluid flow and heat transfer characteristics of three types
of plate fin-and-tube surfaces are numerically investigated, plain plate
fin-and-round tube, slotted plate fin-and- round tube, and slotted plate
fin-and oval tube. The ratio of the long axis over the short one of the
oval tube is 2.25 with the same perimeter length as the round tube. The
strips in the slotted fin surfaces are arranged radially, with more
strips located in the downstream part of the fin surfaces. It is found
that the heat transfer rate of the two slotted fin surfaces is
appreciably higher than that of the plain one, and the pressure drop of
the oval tube slotted fin surface is much lower than that of the round
tube slotted surface. When the pumping power of the oval tube surface is
2.5% lower than that of the round tube surface, the heat transfer rate
of the oval slotted fin surface is 7% higher than that of the round tube
surface. It is found that the pressure drop of the oval tube is
significantly lower than that of slotted round-tube fin surface, leading
to its superiority in the thermal-hydraulic performance.
Key words: Enhanced heat transfer mechanism Slotted fin Oval tube
CLC No: TK172
国家973重点基础研究发展规划(G2000026303)和国家自然科学基金(50476046)资助项目.
Received 20040623, received in revised form 20050328
|