2011 International Conference on Alternative Energy in Developing Countries and Emerging Economies
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Multiport minichannel
test section
Copper plate
Heating plate
95 mm
Water outlet
Pressure tap: Outlet
Outlet water temperature
Pressure tap: Inlet
Water inlet
Inlet water temperature
4
3
2
1
5
6
7
10
9
8
Thermocouplesensors
Fig. 2. Schematic diagram of the test section.
III. E
XPERIMENTAL APPARATUS AND METHOD
The schematic diagram of the experimental apparatus
is shown in Fig.1. The main components of the apparatus
are a test section, water loop, and the data acquisition
system. The complete schematic diagram of the test
section is shown in Fig. 2. The test section is an
aluminium rectangular multiport minichannel, in which
each channel has a hydraulic diameter of 1.2 mm, 95 mm
long, and 24 numbers of channels. The regulated DC
power supply is used to provide the voltage for the
heating plate. The voltage and electrical current values
are measured by a multimeter (Fluke 336 meter) which
has uncertainty of ±2% for voltage and ±1% for current.
The copper plate with 5 mm thickness was installed
between the multiport minichannel tube and DC heating
plate. The uncertainty of the electrical power from the
heating tape is ±2.24%.
The close loop of water consist of the 60 L storage
tanks, a 1200 W electrical heater, and cooling coil
immerged inside the storage tank. The temperature of
water was kept constant as required value via electrical
heater and R134a cooling system by temperature
controllers. After the temperature of the water is adjusted
to achieve the desired value, the water is pumped out of
the storage tank, and is passed through a flow meter, a
test section, and returned to the storage tank. The flow
rates of the water are regulated by adjusting the
controlled valve and measured by the flow meters
installed before entering the test section. The T-type
thermocouples are installed to measure the inlet and
outlet of water temperature, the tube wall temperature,
and the storage tanks temperature. The pressure
transducer (Model: Baumer E913) was installed to
measure the pressure drop across the test section.
Experiments were performed with a various
temperatures and flow rates of water entering the test
section. The range of experimental conditions tested in
this study is listed in Table 1. The uncertainties of
measured quantities and calculated parameters are shown
in Table 2.
