| Test: |
Thermal Conductivity |
| Goal: |
Transfer heat using TSD BN
coating |
| Application: |
Heat exchanger |
| Test Date: |
October 15, 2004 |
| Test Subject: |
7x5x 94ksi aluminum-scandium
tubing (51.2mm ID x 1067mm L x 1.3mm Thick) |
| Room
Temperature: |
77.54°F |
|
Test 1: Tube NOT Coated with TSD BN Thermal Coating (Blue
Version) |
|
|
Time
(Minutes) |
Room Temperature
(F)
|
Exhaust Air Temperature
(F)
A |
Intake Blower Air Temperature
(F)
E |
Tube Surface Temperature
(F)
B |
Tube Surface Temperature
(F)
C |
Tube Surface Temperature
(F)
D |
|
0 |
77.54° |
77.54° |
194.36° |
78.80° |
78.80° |
78.80° |
|
3 |
77.54° |
175.1° |
194.36° |
82.40° |
96.80° |
109.40° |
|
6 |
77.54° |
182.12° |
194.36° |
88.34° |
105.80° |
122.00° |
|
9 |
77.54° |
182.66° |
194.36° |
88.16° |
106.34° |
122.18° |
|
Test 2: Tube Coated with TSD BN Thermal Coating (Blue Version) |
|
Time
(Minutes) |
Room Temperature
(F)
|
Exhaust Air Temperature
(F)
A |
Intake Blower Air Temperature
(F)
E |
Tube Surface Temperature
(F)
B |
Tube Surface Temperature
(F)
C |
Tube Surface Temperature
(F)
D |
|
0 |
77.54° |
77.54° |
194.36° |
78.80° |
78.80° |
78.80° |
|
3 |
77.54° |
174.74° |
194.36° |
103.28° |
111.92° |
138.20° |
|
6 |
77.54° |
175.64° |
194.36° |
103.28° |
111.20° |
140.00° |
|
9 |
77.54° |
175.46° |
194.36° |
103.10° |
111.56° |
140.00° |
 |
※Exhaust Air Comparison
The test shown exhaust air temperature greatly reduced
with tube coated with BN coating. At 9 minute of testing, the
exhaust air temperature was at
175.46°
(tube w/TSD coating) compared to 182.66°
(tube w/o TSD
coating). |
※Test Conclusion
First off, two aluminum tubing for subject test to compare how the
subject will able to dispense heat quicker with boron nitride coated.
One tube was coated with boron nitride.
A heat blower placed at the end of tube, blow the hot air in from one
end and measured the exit air temperature at the other end. Air blower
cooled the tube exterior at giving room temperature.
The test
result showed that the boron nitride able to attract heat from the alloy and
transfer the heat to be cooled down by air. The boron nitride also
creates a semi-rough surface in which increase the air contact surface.
(see drawing on the left)
With the
increase of air surface temperature and excellent BN thermo property, our
test showed 20 degree F hotter from the surface of the tube coated with TSD
boron nitride. This showed the heat was quickly transferred from inner
tube surface onto boron nitride and cooled by the air. The exhaust air
was 7°
cooler with straight tube coated with boron nitride.
The straight
tube allowed hot air passed through the tube without being cooled by tube
inner wall. Thereof, the straight tube was not a good heat exchanger.
If the test
conducted on actually heat exchanger, the result will
significantly
show lower
exhaust air temperatures
with boron nitride
coating.
We concluded
that the boron nitride is an excellent property to be coated onto oil
cooler, intercooler, radiator, etc. in which the item required to be cooled
by air.
|
