are easy in construction and extensively use in
many of the industries. Continuous research is going on to improve its effectiveness
by reducing the thermal boundary layer thickness and increasing the heat transfer
surface area. Perforations in the fins one way that used to improve its effectiveness.
An experimental study submitted to investigate the heat transfer by natural
convection in a rectangular perforated fin plates. Five fins used in this work first fin
non-perforated and others fins perforated by different shapes these fins perforation
by different shapes (circle, square, triangle, and hexagon) but these perforations have
the same cross section area(113 mm2. These perforations distributed on 3 columns
and 6 rows. Experiments produced through in an experimental facility that was
specifically design and constructed for this purpose.
The results show that the drop in the temperature of the non-perforated fin from 72 to
57 oC while the temperature drop in perforated fins, at the same power supplied (126
W) was (72-52 oC), (72-51.5 oC), (72-50 oC) and (72 -48 oC) for shapes (hexagonal,
square, circular and triangular) respectively Figure(9). The largest value of RAF at
triangular perforation and the smaller value occurred in circular perforation. Also,
triangular perforation gives best values of heat transfer coefficient and then the
circular, square, hexagonal, and non-perforation respectivel
الملخص الانجليزي
Extended surface heat exchangers are easy in construction and extensively use in
many of the industries. Continuous research is going on to improve its effectiveness
by reducing the thermal boundary layer thickness and increasing the heat transfer
surface area. Perforations in the fins one way that used to improve its effectiveness.
An experimental study submitted to investigate the heat transfer by natural
convection in a rectangular perforated fin plates. Five fins used in this work first fin
non-perforated and others fins perforated by different shapes these fins perforation
by different shapes (circle, square, triangle, and hexagon) but these perforations have
the same cross section area(113 mm2. These perforations distributed on 3 columns
and 6 rows. Experiments produced through in an experimental facility that was
specifically design and constructed for this purpose.
The results show that the drop in the temperature of the non-perforated fin from 72 to
57 oC while the temperature drop in perforated fins, at the same power supplied (126
W) was (72-52 oC), (72-51.5 oC), (72-50 oC) and (72 -48 oC) for shapes (hexagonal,
square, circular and triangular) respectively Figure(9). The largest value of RAF at
triangular perforation and the smaller value occurred in circular perforation. Also,
triangular perforation gives best values of heat transfer coefficient and then the
circular, square, hexagonal, and non-perforation respectively.
رائد رشاد جاسم | Raaid Rashad Jassem | 4589