STUDI EKSPERIMENTAL PERPINDAHAN KALOR KONVEKSI FLUIDA NANO Al2O3-PROPHYLENE GLYCOL PADA CIRCULAR TUBE DI BAWAH KONDISI FLUKS KALOR KONSTAN
Abstract: This research
was conducted to
examine the thermal
conductivity and heat transfer
characteristic of Al2O3-prophylene glycol
nanofluid on a
circular tube heat exchanger
under constant heat flux conditions. Al2O3 nanoparticles with nominal
diameter of 13 nm were dispersed in prophylene glycol as base fluid at three
different particles concentration
of 0,2%, 0,5%, and 1,0% w/v, respectively. A straight horizontal
stainless-steel tube of 1,2 m length, 0,005 m inner diameter
and 0,0063 m
outer diameter was
used as a
test section. A nickelin coil heater was connected to an AC
regulated power supply to obtain constant
wall heat-flux boundary
condition. The flow
rates were adjusted
to obtain the Reynolds
number specification from
75 to 215.
The result shows that
the effective thermal
conductivity increases from
its base fluid.
The highest enhancement of
thermal conductivity of
the observed nanofluids
is 4,80% for nanoparticles
concentration of 1,0%
w/v. For the
same Reynolds number, heat
transfer increases with the increase of the Nusselt number from base fluid
to nanofluids at
x/Di = 200 with
the highest value
of 27,61% for 1,0%
w/v. At the
Reynolds number variation,
the highest Nusselt
number enhancement at x/Di = 200 reaches 43,49% from Reynolds number 75
to 215 for alumina concentration of 1,0% w/v.
Keywords: Heat transfer
coefficient, Nanofluids, Particle concentrations, Thermal conductivity, Al2O3
nano particle
Kode Jurnal: jptmesindd120019
