IRLab Quantitative Thermography

Images collected with infrared thermography can be very useful for gaining insight into thermal phenomena such as thermal bridging and natural convection. But as a research tool it is even more valuable to extract numerical data from the images and produce maps of surface temperature.  This is called quantitative infrared thermography and can be very challenging.  We have developed procedures that allow collecting and processing the infrared data to enable obtaining results that are as accurate as possible.  The main difficulties in using infrared to measure temperature are correcting the measurement for reflected radiation and proper referencing of the relative radiometric measurement.  Efforts are underway to develop standardized test procedures for using infrared to quantify surface temperatures in the types of thermal test chambers used to test building products.  But for now, information on how we perform quantitative thermography is available in some of our technical papers.  One of these papers presents temperature results for a series of insulated glazing units.  This is an example of our goal to make available a database of surface temperatures results for various types of windows.  These data sets are available for download at the link below.  The data are for the warm side surface of various types of air-filled insulating glazing units subjected to ASHRAE winter design conditions and are similar to the graph below. 
 

tempgraph.JPG (17010 bytes)
This graph shows the distribution of surface temperatures down the middle of a typical dual-pane, insulated glazing unit.  This unit has aluminum spacers and a 1/2" gap. The thermal image of the entire glazing is also available.

  

           Technical paper on the surface temperatures of insulated glazing units

           Download text data of IGU surface temperatures

 

For more information on Infrared Thermography Laboratory research and facilities contact:

Howdy Goudey
Building Technologies Program
510-486-6046 (fax)