STUDI EKSPERIMENTAL KARAKTERISTIK PERPINDAHAN PANAS DAN FAKTOR GESEKAN PADA PIPA PENUKAR KALOR BERPENAMPANG BUJURSANGKAR DENGAN HALF LENGTH DAN FULL LENGTH TWISTED TAPE INSERT
Abstract: The work
presents an experimental
study on the
mean Nusselt number, friction factor
and thermal performance
characteristics in the
inner tube (square duct)
of a concentric
tube heat exchanger
with half length
and full length twisted
tape insert. In the experiments,
measured data are
taken at Reynolds number range
between 4000 and 16,000 with water as the test fluid. The full length twisted
tape is inserted into the test tube at single twist ratio of y/w = 4.0 while
the half length twisted tape with the equal twist ratio mounted at the
entry test section.
The half length
twisted tape is
introduced as a swirling flow device for generating a
strong swirl flow at the tube entry until the half tube length before decaying
along the tube.On the other hand, the full length twisted
tape is expected
to produce a
strongly swirling flow
over the whole tube.
The variation of
heat transfer and
pressure loss in
the form of Nusselt
number (Nu) and
friction factor (f)
respectively is determined
and depicted graphically. The experimental result indicates that heat
transfer rate and friction factor
associated by the
half length and
full length twisted
tape consistently higher than those without twisted tape insert (plain
tube). Under the similar operating
conditions, the half
length twisted tape
perform lower Nusselt number
and friction factor
values than the
full length twisted
tape around 48.67% and
82.22%, respectively.In addition,
it is apparent that
the thermal performance of
the inner tube
with the half
length twisted tape
is found to be lower than that with the full length one.
Keywords: Friction factor, Full
length twisted tape, Half length twisted tape, Nusselt number, Reynolds number
Penulis: Tri Istanto, Wibawa
Endra Juwana, Indri Yaningsih
Kode Jurnal: jptmesindd130148
