thermal conductivity

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thermal conductivity

n.
A measure of the ability of a material to allow the flow of heat from its warmer surface through the material to its colder surface, determined as the heat energy transferred per unit of time and per unit of surface area divided by the temperature gradient, which is the temperature difference divided by the distance between the two surfaces (the thickness of the material), expressed in watts per kelvin per meter.

thermal conductivity

n
(General Physics) a measure of the ability of a substance to conduct heat, determined by the rate of heat flow normally through an area in the substance divided by the area and by minus the component of the temperature gradient in the direction of flow: measured in watts per metre per kelvin. Symbol: λ or k Sometimes shortened to: conductivity
References in periodicals archive ?
Few studies have addressed the need for new testing standards for the determination of the SHGC, U-factor, and electrical performance of STPV systems (and building integrated photovoltaic technologies in general).
Also, the windows selected were high performance, having a total unit performance U-factor of 0.
With a good U-factor and SHGC, Solarban 70XL glass also reduced the chance that the space will overheat, which is very important in our naturally cooled space.
Which of the following statements about U-factor and R-value are true?
The glass is a high performance Softcoat Low Emissivity (Low E) glass to achieve a lower U-factor (heat loss/gain) or Solar Heat Gain Coefficient (SHGC) The glass is sprayed with a coating of metal oxide particles that produce a higher heat reflectance.
For instance, requirements associated with building envelope assemblies have evolved from a single overall average U-factor to specific requirements for each product or material used in each building envelope component.
The thermal models for the prediction of the U-factor were compared with the measurement data taken from the certified product directory database of the National Fenestration Rating Council (NFRC) and CFD simulations.
Alpen High Performance products 9H and L series windows, averaging U-factor of 0.
The curtainwall provides enhanced condensation performance and tow U-Factor, along with panoramic, floor-to-ceiling views.
Specific guidelines for U-factor and solar heat gain coefficient (SHGC) of replacement glass; minimum R-values for insulation; exemptions for lighting replacements of less than 50% of a space, as well as bulb and ballast-only lighting alterations, so long as these don't result in increased power consumption; and requirements for door and roof replacements, as to when additional insulation is mandated, and when it is not.
The National Fenestration Rating Council is a good first stop, since o it rates windows on factors like air leakage and offers a U-factor measurement of how well the window guards against heat loss.