In the present work of heat transfer for hexagonal fins (1mm & 2mm)
grooves on surface and threaded fin is addressed. The test has been performed
on three different fin geometries having hexagonal (1mm)groove,
hexagonal(2mm)groove, threaded fin(0.5mm)pitch and test performed by using
a centrifugal blower, test section, heater and
test panel and Results are obtained for temperature distribution, effectiveness,
efficiencies at a same flow rate of air as it was conducted in forced convection
and the same parameters considered for different values are obtained for
natural convection with different fins as well. In this experiment for forced
convection, the airflow rate is constant i.e, 2.3371 m/sec throughout the
experiment. In natural convection, efficiency for the threaded fin is high with
93.89% and effectiveness of hexagonal (2mm)depth fin is 28.11. In forced
convection, the efficiency of the threaded fin is high with 81.83% and
effectiveness of hexagonal (1mm)depth fin is high with 23.51 was recorded. The
heat transfer rate is higher in natural convection is hexagonal(2mm)depth fin
with 11.41 watts and 21.75 watts in forced convection with
Keywords: Pin-fins, Hexagonal fin, Threaded fin, Efficiency, Effectiveness.
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