emissivity


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e·mis·siv·i·ty

(ē'mi-siv'i-tē),
The giving off of heat rays; a perfect "black body" has an emissivity of 1, a highly polished metallic surface may have an emissivity as low as 0.02.

emissivity

(ĕm″ĭ-sĭv′ĭ-tē)
The ability of a substance or surface to emit radiant energy.
References in periodicals archive ?
Within the cavity, the absorptivity must equal the emissivity.
The current low-e coatings have an emissivity approaching zero and reduce radiation heat transfer.
However, the emissivity and heat capacity of the materials themselves should also be taken into account to ensure a good cooling performance when these materials are coated with a high reflective coating.
The approach taken in this study is to simplify the model to the essential elements so as to be able to understand the effects of key model parameters with particular emphasis on the emissivity of the surface.
The generalized emission equation given in (4) can be used to derive a method for characterizing the emissions of mobile sources of an urban area, by describing the emissivity R of its roadway segments; the size of the roadway segments can be selected based on the characteristics of the district area and the spatial scale of the study.
The blades are made of polished metal so that the assembly has a low effective emissivity when the blades are closed to cover the baseplate.
In case of satellite measurements, the surface associated with a pixel is not in thermal equilibrium and is composed of areas with different characteristics of reflectance and emissivity.
It's a somewhat thorny distinction, but you shouldn't go astray if you can remember two things: first, the lower the U-Factor the more insulated the window, and second, since a window's U-Factor is the measure of its Emissivity, a LowU window will most often be referred to as a Low-E window.
Heat Mirror has low emissivity and solar reflective film inside of an insulating glass unit.
With a user interface designed for intuitive operation and available in six languages, users can access advanced features such as adjustable emissivity, alarms and data logging with a few pushes of a button via a soft-key menu displayed on the dot-matrix LCD screen.
Because it is a low emissivity (low-e) surface, DuPont Tyvek ThermaWrap increases the thermal performance of walls by ultimately reducing the transfer of radiant heat both into and out of homes.