I remember seeing a report by Jeff Christian of ORNL decades ago
that looked into the change in conductivity for insulation
products as a function of temperature. I recall he found
something like a 10% change over the range of ambient
temperatures. If you're interested, you should do a Google Search
of the technical literature (or ORNL reports) and see if you find
something.
Joe
Joe Huang White Box Technologies, Inc. 346 Rheem Blvd., Suite 205A Moraga CA 94556 yjhuang@xxxxxxxxxxxxxxxxxxxxxxxx http://weather.whiteboxtechnologies.com for simulation-ready weather data (o) (925)388-0265 (c) (510)928-2683 "building energy simulations at your fingertips"
On 1/11/2017 10:42 PM, Amrita Ghosh
amritaghosh1986@xxxxxxxxx [EnergyPlus_Support] wrote:
Hi,
Can anyone tell me if U-value of a material changes with temperature?
While evaluating the U-value, if the convective heat transfer coefficients (h) change, the U-value changes. But does it also change when the temperature, indoor or outdoor, changes? Since the equation states: U=Q/(A. deltaT)where deltaT= temperature difference between indoor and outdoor.
Thank you,Amrita
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