Thermal Resistance

thermal resistance

[′thər·məl ri′zis·təns]

(electronics)

effective thermal resistance

(thermodynamics)

A measure of a body's ability to prevent heat from flowing through it, equal to the difference between the temperatures of opposite faces of the body divided by the rate of heat flow. Also known as heat resistance.

McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

Thermal resistance

The resistance (R-value) to the passage of heat provided by the roof, walls, or floors of a building.

Illustrated Dictionary of Architecture Copyright © 2012, 2002, 1998 by The McGraw-Hill Companies, Inc. All rights reserved

thermal resistance

The reciprocal of thermal conductance.

McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.

The following article is from The Great Soviet Encyclopedia (1979). It might be outdated or ideologically biased.

Thermal Resistance

 

(or heat resistance), the capacity of the surface or a layer of a body to resist the propagation of thermal molecular motion.

A distinction is made between (1) total thermal resistance, which is the reciprocal of the heat-transmission coefficient, (2) surface thermal resistance, which is the inverse of the heat-transfer coefficient, and (3) thermal resistance of a layer, which is equal to the ratio of the thickness of the layer to its thermal conductivity. The thermal resistance of a complex system—for example, multilayer thermal insulation—is equal to the sum of the thermal resistances of its parts. Thermal resistance is numerically equal to the thermal head required for the transfer of a unit of heat flow of 1 watt per sq m to the surface of a body or through a layer of a substance and is expressed in m² · °K/W.

The Great Soviet Encyclopedia, 3rd Edition (1970-1979). © 2010 The Gale Group, Inc. All rights reserved.