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EN 1992-1-2 deals with the design of concrete structures for the accidental situation of fire exposure and is intended to be used in conjunction with EN 1992-1-1 and EN 1991-1-2. This part 1-2 only identifies differences from, or supplements to, normal temperature design. Part 1-2 of EN 1992 deals only with passive methods of fire protection.
Conversely, thermal resistance (R) measures the opposition to the heat current in a material or system. It is measured in units of kelvins per watt (K/W) and indicates how much temperature difference (in kelvins) is required to transfer a unit of heat current (in watts) through the material or object.
The construction industry makes use of measures such as the R-value (resistance) and the U-value (transmittance or conductance). Although related to the thermal conductivity of a material used in an insulation product or assembly, R- and U-values are measured per unit area, and depend on the specified thickness of the product or assembly.
Thermal contact resistance is significant and may dominate for good heat conductors such as metals but can be neglected for poor heat conductors such as insulators. [2] Thermal contact conductance is an important factor in a variety of applications, largely because many physical systems contain a mechanical combination of two materials.
In heat transfer, the thermal conductivity of a substance, k, is an intensive property that indicates its ability to conduct heat. For most materials, the amount of heat conducted varies (usually non-linearly) with temperature. [1] Thermal conductivity is often measured with laser flash analysis. Alternative measurements are also established.
It is also used to construct valves for molten zinc. [11] Molybdenum is used in mercury wetted reed relays, because molybdenum does not form amalgams and is therefore resistant to corrosion by liquid mercury. [12] [13] Molybdenum is the most commonly used of the refractory metals. Its most important use is as a strengthening alloy of steel.
According to the United States Department of Energy, in 2018 process heat accounted for approximately 50% of energy use in the manufacturing sector, as well as 30% of Greenhouse gas emissions. [1] Accordingly, it is the target of significant efforts to introduce new forms of carbon neutral or at least lower carbon process heat supplies.
A heating element is a device used for conversion of electric energy into heat, consisting of a heating resistor and accessories. [1] Heat is generated by the passage of electric current through a resistor through a process known as Joule heating. Heating elements are used in household appliances, industrial equipment, and scientific ...