ISO 14934-1:2010 火災試験—熱流束計の校正と使用—パート1：一般原則 | ページ 6

3.1.1

radiation

emission or transfer of energy in the form of electromagnetic waves with the associated photons

Note 1 to entry: See Reference [1].

3.1.2

heat

energy transferred from one body or system to another due to a difference in temperature

Note 1 to entry: See Reference [3].

Note 2 to entry: Heat is expressed in joules.

3.1.3

heat transfer

transfer of energy from one body or system to another as a result of a difference in temperature

Note 1 to entry: The bodies can be a gas, liquid, solid body, or some combination.

Note 2 to entry: Heat transfer is expressed in watts.

Note 3 to entry: Adapted from definition of ‘heat transfer’ contained in Reference [3].

3.1.4

convection

transfer of heat by movement of a fluid

[SOURCE: ISO 13943:2008, definition 4.54]

3.1.5

heat flux

amount of thermal energy emitted, transmitted or received per unit area and per unit time

Note 1 to entry: Heat flux for fire testing purposes is expressed in watts per square metre.

Note 2 to entry: Outside the fire testing field this definition is given as “heat flux density”.

Note 3 to entry: Adapted from ISO 13943:2008, definition 4.173.

3.1.6

radiosity

total of radiative heat flux emitted and radiative heat flux reflected leaving a surface when no radiative heat flux is transmitted

Note 1 to entry: See Reference [4].

Note 2 to entry: This definition is relevant to method 1 of ISO 14934-2.

Note 3 to entry: Radiosity is expressed in watts per square metre.

3.1.7

black-body radiation source

ideal thermal radiation source which completely absorbs all incident heat radiation, whatever wavelength and direction

Note 1 to entry: Adapted from ISO 80000-7:2008.

Note 2 to entry: A more physical definition of black body radiation source is given in ISO 13943.

3.1.8

irradiance

incident radiative heat flux arriving from all hemispherical directions

Note 1 to entry: Irradiance is expressed in watts per square metre.

3.1.9

emissivity

ratio of the radiation emitted by a radiant source to the radiation that would be emitted by a black-body radiation source (3.1.7) at the same temperature

Note 1 to entry: Emissivity is dimensionless.

[SOURCE: ISO 13943:2008, definition 4.75]

3.1.10

absorptivity

ratio of the absorbed radiant heat flux to the incident radiative heat flux

Note 1 to entry: Absorptivity is dimensionless.

3.1.11

radiative intensity

radiative heat flux per unit solid angle leaving a source in a given direction

Note 1 to entry: Radiative intensity is expressed in watts per steradian.

Note 2 to entry: See Reference [5].

3.1.12

heat flux meter

instrument responding to incident radiative heat transfer, or convective heat transfer to a cooled surface, or both

3.1.13

radiometer

heat flux meter responding to incident radiative heat flux only

3.1.14

total hemispherical radiometer

radiometer equally sensitive to radiative intensity arriving from all directions above the sensing surface

3.1.15

total heat flux meter

heat flux meter responding to both incident radiative heat transfer and convective heat transfer to a cooled surface

Note 1 to entry: The expression “heat flux meter” without the denotation “total” is typically used only when it is not specified whether the instrument is a radiometer or a total heat flux meter.

3.1.16

primary standard

standard that is designated or widely acknowledged as having the highest metrological qualities and whose value is accepted without reference to other standards of the same quantity

[SOURCE: ISO/IEC Guide 99]

3.1.17

secondary standard heat flux meter

heat flux meter with a calibration traceable to a primary standard, used only for calibration of working-standard heat flux meters

3.1.18

working-standard heat flux meter

heat flux meter calibrated by reference to a secondary standard for subsequent use during the course of fire tests

3.1.19

sensing surface

surface of the heat flux meter that detects the irradiance

3.1.20

sensitivity

ratio of the output voltage to the measured quantity

3.1.21

Stefan-Boltzmann constant

σ

constant of proportionality in the expression in the Stefan-Boltzmann law for calculating the radiative heat flux from the absolute temperature

Note 1 to entry: This constant is equal to 5,670 400 × 10⁻⁸ watts per square metre and per kelvin to the fourth power.

Note 2 to entry: See Reference [2].