Differences

This shows you the differences between two versions of the page.

--- planning:thermal_protection:thermal_protection_works:insulation_works_-_evidence_no.1_measurements_at_a_highly_insulated_wall [2019/02/21 11:30] – cblagojevic
+++ planning:thermal_protection:thermal_protection_works:insulation_works_-_evidence_no.1_measurements_at_a_highly_insulated_wall [2022/01/25 10:53] (current) – ggrosskopf
@@ Line 48: / Line 48: @@
 =====  Very low heat flows  =====
-Since all three temperature curves are very close together we can see that little heat escapes from the exterior surface of the brick wall: If that were the case the exterior of the brick would be a lot colder than the center of the brick and even more so than the interior surface. Yet, the temperature measured at the exterior of the brcik is hardly below that of the interior plaster: at an average of 23.4 degrees Celsius on the outside and 24.1 degrees on the inside.
+Since all three temperature curves are very close together we can see that little heat escapes from the exterior surface of the brick wall: If that were the case the exterior of the brick would be a lot colder than the center of the brick and even more so than the interior surface. Yet, the temperature measured at the exterior of the brick is hardly below that of the interior plaster: at an average of 23.4 degrees Celsius on the outside and 24.1 degrees on the inside.
 These findings can even be used for a rough estimation of quantitative results: The mean temperature decrease in the brick part, including the layer of interior plaster, amounts to 0.63 degrees, and to 19.4 degrees between the exterior surface of the brick wall and the external plaster on the insulation layer. This means that the insulating effect provided by the insulation layer is increased by a factor of 19.4/0.63 ≈ 31 compared with that of the brick wall. This result is even better than the theoretical value of approx. 28.5 resulting from a simple U-value calculation: In building physics, the “insulating effect“ is defined as the thermal resistance of a building component resulting from its thickness divided by its thermal conductivity. The factor of 31 is deliberately called a “rough estimate” and would only be obtained precisely if the temperatures inside the components were exactly identical at the beginning and end of the time period. However, this is not the case. More exact calculation results will only be obtained by looking at a much longer timeframe. In that case, a variation in temperature at the beginning and end of the period would play a minor role.\\