STUDI EKSPER-IMENTAL PERPINDAHAN KALOR KONVEKSI FLUIDA NANO TIO2-ETHYLENE 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 TiO2-ethylene glycol
nanofluid on a
circular tube heat exchanger
under constant heat
flux conditions. TiO2 nanoparticles with nominal diameter of 21 nm were dispersed
in ethylene 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
400 to 700. The
result shows that the
effective thermal conductivity
increases from its base fluid.
The highest enhancement of
thermal conductivity of
the observed nanofluids
is 8,62% 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
30,55% for 1,0% w/v.
At the Reynolds
number variation, the
highest Nusselt number enhancement at x/Di = 200 reaches
73,6% from Reynolds number 400 to 700 for titania concentration of 1,0% w/v.
Keywords: Heat transfer
coefficient, Nanofluids, Particle concentrations, Thermal conductivity, TiO2
nano particle
Kode Jurnal: jptmesindd120004
