where expertise comes together - since 1996 -

The Largest Open Access Portal of Nondestructive Testing (NDT)

Conference Proceedings, Articles, News, Exhibition, Forum, Network and more

where expertise comes together
- since 1996 -

FI Test- und Messtechnik GmbH

780 views
Technical Discussions
zaki
, Joined ,

zaki

,
Joined

09:19 Nov-27-2002
IR Thermography


Just for curiosity..

In Thermography method, measurement appear in Temperature (oC), but theoritically the measurement is performed in term od total receiving radiation power (W). Is there any relationship between temperature vs. radiation..



    
 
 
Alberto Monici
Engineering, Leak Detection Service - Thermography Service -
ETS Sistemi Industriali, Italy, Joined Aug 2002, 17

Alberto Monici

Engineering, Leak Detection Service - Thermography Service -
ETS Sistemi Industriali,
Italy,
Joined Aug 2002
17
09:55 Nov-27-2002
Re: IR Thermography
Dear Mr.Zaki
For a black-body the relationship is that gived by Plank's law, in wich:
W= (2*pi*h*c^2)/((lambda^5)(e^(hc/lambdakT)-1))
in which W is the spectral emissivity [Watt/m^2*meter] and T is the black-body temperature in Kelvin.
The intergal of the Plack formula in all the lambda possible give the Total Energy Emission (Stefan-Boltzmann law):
Wt=k*T^4
where k is the Stefan-Boltzmann constant.
For a grey-Body (like that normally measured in nature), the emissivity of the body, its spectral transmittance and the spectral absorbing coefficient give a total emittance below then a black-body. So the formula is: Wt=E*k*T^4, where E is the ratio between emittance of grey and black bodies.
I Hope to be exhaustive for your couriosity. Don't exitate to contatct me for any other question.


:
: Just for curiosity..
.
: In Thermography method, measurement appear in Temperature (oC), but theoritically the measurement is performed in term od total receiving radiation power (W). Is there any relationship between temperature vs. radiation..
.



    
 
 
Robert Paynter
R & D, Research Assistant
U of Oxford, United Kingdom, Joined Jun 2001, 14

Robert Paynter

R & D, Research Assistant
U of Oxford,
United Kingdom,
Joined Jun 2001
14
01:33 Dec-02-2002
Re: IR Thermography
Alberto Monici wrote:
: Dear Mr.Zaki
: For a black-body the relationship is that gived by Plank's law ...

:: Just for curiosity..
:
: In Thermography method, measurement appear in Temperature (oC), but theoritically the measurement is performed in term od total receiving radiation power (W). Is there any relationship between temperature vs. radiation..
: .
.
Alberto Monici gave the total, but most sensors have a limited band of detection and you need to allow for that. CMT (Cadmium/Mercury/Telluride) is the favourite at typical ambient temperatures because it's response ends up being almost linear in this range. InSb (Indium Antimonide) can do these low temperatures but is much better (more linear) at higher (600K +).
They are well behaved responses so will be calibrate within the camera.

As a user you need to take care that the emission of your observed surfaces is taken into account - some are unexpectedly good with IR eg. white snow.

Robert


    
 
 

Product Spotlight

Digital Radiography for Concrete Inspection

In the construction industry (buildings, bridges) there is a need for fast non- destructive means,
...
most commonly to locate targets (Pipes, Re-bars, Conduit, Fittings etc.) within concrete structures prior to drilling, cutting or coring. Measuring reinforcements is also performed for static calculations and to detect corrosion problems and damages. Cracks and voids can also be visualized. The examinations are not only restricted to concrete constructions; they can also be applied to reinforced masonry made of natural stones or bricks.
>

GEKKO, Standard and Advanced phased-array for Easier inspection

With a 64-channel parallel architecture, GEKKO is a flaw detector offering at the same time conven
...
tional UT, standard PAUT, TOFD and real-time Total Focusing Method (TFM). GEKKO improves the detection, with better defects characterization and sizing as well as for misoriented defects. Some procedures require standard UT, others TOFD or PA. GEKKO includes all these techniques to offer a versatile and field-ready equipment. - 64:64 parallel channels - + 4 additional TOFD - Conventional UT channels - International code compliance: ASME, AWS, API, ASTM, ISO-EN Watch the video: https://youtu.be/kuEY_RwWS3Q
>

Webinar: FMC & Advanced Focusing Techniques for Improved Ultrasonic Inspections

Phased array ultrasound is now a commonly accepted inspection technology. Now there is excitement ar
...
ound new techniques in Phased Array: Full Matrix Capture (FMC) & Total Focusing Method (TFM). Our webinar on December 5 & 6 will illustrate how these techniques, implemented on a TOPAZ64 instrument, can improve the results of existing inspections. Register today.
>

MUSE Mobile Ultrasonic Equipment

The MUSE, a portable ultrasonic imaging system, was developed for in-field inspections of light-weig
...
ht structures. The MUSE consists of a motor-driven manipulator, a water circulation system for the acoustic coupling and a portable ultrasonic flaw detector (USPC 3010). The MUSE provides images of internal defects (A-, B-,C- and D-scan).
>

Share...
We use technical and analytics cookies to ensure that we will give you the best experience of our website - More Info
Accept
top
this is debug window
s