thermal transmittance


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Related to thermal transmittance: Thermal conductivity

thermal transmittance, U-value

The time rate of heat flow per unit area under steady conditions from the fluid on the warm side of a barrier to the fluid on the cold side, per unit temperature difference between the two fluids.
References in periodicals archive ?
showed their work of "Thermal transmittance of window systems and effects on building heating energy use and energy efficiency ratings in South Korea." And they measured the thermal performance (U-factor) of different window systems and analyzed their effects on energy savings.
* desired air leakage rate and thermal transmittance of the building's envelope were not achieved in the case of the community centre;
The results of the matrix calculation are two complex values, thermal admittance [Y.sub.nn] and thermal transmittance [Y.sub.mn] which can be expressed by the amplitude and phase shift.
Table Modeled building energy performance Building energy Thermal transmittance [U.sub.N], W/[m.sup.2]K performance class Walls Floor Roof Windows Doors A 0.12 0.14 0.10 1.00 1.00 A+ 0.11 0.12 0.09 0.85 0.85 A++ 0.10 0.10 0.08 0.70 0.70
Energy properties of the building Average thermal transmittance 0.115 Thermal capacity 17.84 of non-transparent areas of external walls, of envelope, W/[m.sup.2]K MJ/K Average thermal transmittance 0.79 Thermal capacity 34.29 of transparent areas of of internal envelope, W/[m.sup.2]K partitions, MJ/K Air change rate of the 0.39 Time constant of 277 building at 50 Pa pressure active internal difference, [h.sup.1] surfaces, h Internal heat gains, 2.1 W/[m.sup.2](Feist et al.
The thermal transmittance value of glass results in much higher heat loads than one gets with solid insulated walls.
The latest benefit to emerge from green facades and roofs is thermal transmittance. Layers of greenery increase insulation properties by reducing wind velocity on a building's envelope.
The effect of vertical air gaps to thermal transmittance of horizontal thermal insulating layer, Journal of Civil Engineering and Management 15(3): 309-315.
Among the sustainable measures incorporated into the final design of 1347 Bristow Street are a condensing gas-fired boiler with flat panel hydronic radiators equipped with thermostats; fiberglass-framed windows with low thermal transmittance values; and energy-efficient appliances and lighting.
Insulated sections within the doors comply with UK building regulations for thermal transmittance and provide good weather resistance.
Knowledge of the thermal transmittance of insulating pallet and cage cover materials is of considerable importance in determining their suitability tot use in the transport, movement and storage of ambient, chilled and frozen food products.