high temperature measurementby thermography on csp, jesús
TRANSCRIPT
Dr. Jesús BallestrínCIEMAT-Plataforma Solar de Almería (SPAIN)
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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HIGH TEMPERATURE MEASUREMENTBY THERMOGRAPHY ON CSP
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Visible range Snake IR vision
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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CCD spectral responseHuman eye response
4th SFERA Summer SchoolMay 15-16, 2013. Hornberg Castle, GERMANY
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Visible range Infrared range
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Visible range Infrared range
4th SFERA Summer SchoolMay 15-16, 2013. Hornberg Castle, GERMANY
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Radiation is the principal way that heat and energy travelthrough the universe.
THERMAL RADIATIONAll matter with a temperature greater than absolute zero emitsthermal radiation. This radiation increases with temperature.
Solar
Solar: 0.1- 4 m5760 K
Solar Thermal
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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1. A blackbody absorbs all incident radiation, regardlessof wavelenght and direction.
2. For a certain temperature and wavelenght, no surface canemit more energy than a blackbody.
3. Altough the radiation emitted by a blackbody is a function ofwavelenght and temperature, it is independient of direction.That is, the blackbody is a diffuse emitter.
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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4th SFERA Summer SchoolMay 15-16, 2013. Hornberg Castle, GERMANY
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0
bE
0d
][)1(
1225/
12
nmmW
neCE TnCb
Planck’s law
][ 2
0
4
mWTdEE bb
Stefan-Boltzmann’s law
][10898.2 6max KnmT
Wien's displacement law Irrad
ianc
e, W
m-2
nm
-1
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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][1067.5 4284
0
KmW
T
dE b
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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),(),,,(
),,,(,
,, TI
TIT
b
e
Emission from real surfaces. Emittance Ɛ
),(),(),(
, TETET
b
Hemispherical spectral
)(
),(),()( 0 ,
TE
dTETT
b
b
Hemispherical
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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IR calibration
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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1
Kirchoff’s law
(T)
),,,(),,,( ,, TT
Opaque
Thermal equilibrium
“A good thermal emitter is a bad reflector and viceversa”
• Perkin–Elmer spectrophotometer in the 175–3300 nm
• Nicolet Magna IR spectrophotometer in the 1350–28500 nm
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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ET 4
d
TdT
41
dddTdT
dTEdT 324
1
• Temperature uncertainty versus Emittance uncertainty
T1
12 % 3% T
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Surface temperature measurement
• High temperatures (> 2000 ºC)
• Low confidence on contact sensors.
• IR detectors: pyrometers and cameras.
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Detector(Pyrometer or IR camera)
Sample
Thermal radiation (Eth)
Solar radiation
Reflected solar radiation (Gr)
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Solar furnace diagram
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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4th SFERA Summer SchoolMay 15-16, 2013. Hornberg Castle, GERMANY
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0 1000 2000 3000 4000 5000
0,01
0,1
1
10
100
1000
0,0
0,1
0,2
0,3
0,4
0,5
0,6
0,7
0,8
0,9
1,0
DNI
Concentrated Solar Radiation
Ref
lect
ance
/ Tr
ansm
ittan
ce
Spec
tral i
rrad
ianc
e [W
m-2 n
m-1]
[nm]
quartz 5mm
B.B. at 500 K
B.B. at 700 K
B.B. at 1100 K
Mirror reflectance
Atmospheric absorption solar bands in a concentrated solar spectrum based on a MODTRAN simulation,black body radiance at several temperatures, quartz transmittance and mirror reflectance.
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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0 1000 2000 3000 4000 50000.01
0.1
1
0
10
20
30
40
50
60
70
80
90
100
700 K
1100 K
R eflected D N I
Ref
lect
ance
/ T
rans
mitt
ance
[%
]
Spec
tral
irra
dian
ce [W
m-2
nm
-1]
W avelength [nm ]
500 K
4275
nm
2710
nm19
00 n
m
M irror reflectance
Q uartz 5m m
4720
nm
3320
nm
2410
nm
Band‐pass filters
Camera transducer: InSb 1500-5000 nm
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Error calculations
FILTERth
FILTERr
FILTERth
FILTERthFILTERrFILTERthFILTERr E
GE
EGEE
)()(
FILTER
FILTER
EdE
TdT
41
)(41)( FILTERrr ET
1)
2)
r(T) ≤ 5%
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Results
Filter Measuring temperature range
Attenuation for solar radiation
Quartztransmittance
(5 mm) = 1900 nm 1080 K ≤ T Atmospheric absorption 93 % = 2410 nm 2000 K ≤ T No attenuation 92 %
= 2710 nm Valid for any T Atmospheric absorption 91 %
= 3320 nm 600 K ≤ T Low reflectivity of the mirrors 86 %
= 4275 nm Valid for any T Atmospheric absorption + Low reflectivity of the mirrors 9 %
= 4720 nm 380 K ≤ T Low reflectivity of the mirrors 0 %
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Thermal radiation attenuation
Beer’s Law
LCL eEE 0
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Thermal radiation attenuation
3.90 3.95 4.00 4.05 4.10 4.15 4.20 4.25 4.30840
845
850
855
860
865
870
875
880
885
890
895
Distance [m]
Tem
pera
ture
[K]
Atmospheric transmissivity test Temperature measurement vs. distance
Black Body Temperature F3320 ([K]) F4720 ([K]) F4275 ([K]) F2700 ([K])
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Error for each selected filter
400 600 800 1000 1200 140016000.01
0.1
1
10
100
1000
Reflectivity 70%
Reflectivity 30%
Reflectivity 50%
Reflectivity 10%
Reflectivity 90%
Rel
ativ
e er
ror [
%]
Temperature [K]
Filter centered at 3320 nm
400 600 800 1000 1200 1400 16000.01
0.1
1
10
100
1000
Temperature [K]
Rel
ativ
e er
ror
[%]
Reflectivity 70%
Reflectivity 30%
Reflectivity 50%
Reflectivity 10%
Reflectivity 90%
Filter centered at 4720 nm
1
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Measurements without quartz window
• Both filters can be used:
Filter centered at 3320 nm. Filter centered at 4720 nm.
Photography Thermography at 3320 nm.
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Temperature correction for quartz window
filtercamera EE
quartzfiltercamera EE 4
filterE
T
4 quartzfilter
W
ET
4quartz
WTT
2000 3000 4000 5000
1E-3
0.01
0.1
1
0
10
20
30
40
50
60
70
80
90
100
DNI Tra
nsm
ittan
ce [%
]
Spec
tral
Irra
dian
ce [W
m-2
nm
-1]
Wavelength[nm]
0.001
4275
nm
2710
nm
1900
nm
Quartz transmittance 5 mm
4720
nm
3320
nm
2410
nm
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Measurements with quartz window
Filter centered at 4720 nm.
• Measurement of the quartz window
Thermography at 4720 nmPhotography
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
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Conclusions
Using the pass‐band filters centered at 3320 and 4720 nm
the measurements are not affected by the reflected solar radiation or by the atmospheric attenuation
allows to measure through quartz windows allows to measure the temperature of the quartz windows the higher the surface temperature, the lower relative error in
the measurement
Nowadays, this camera is being used in the solar furnace of the Plataforma Solar de Almería.
4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
Development of a Radiometry Laboratory
• Two-color pyrometer: 600-1400 ºC (± 0.50 %)
• Two-color pyrometer: 700-2000 ºC (± 0.50 %)
• Solar blind pyrometer: 500-2500 ºC (± 0.30 %)Pass Band Filter: 1390 ± 20 nm
• Spherical black body: 100-1000 ºC (± 0.25 %)
• Cylindrical black body: 300-1700 ºC (± 0.25 %)
• Pyrometer: 600-3000 ºC (± 0.30 %)
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4th SFERA Summer School May 15-16, 2013. Hornberg Castle, GERMANY
• Periodic calibration of heat flux sensors (Present)
• Emittance characterization of material surfaces at high temperatures (Future)
• Periodic calibration of IR pyrometers and cameras (Present)
OBJETIVES OF THE LABORATORY
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