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Radiation

This Documentation refers to Metafor version >= 3593. for more informations on changes see MR !167 for technical informations).

for a Metafor version < 3593, please refers to this page.

RadiativeMaterial

The RadiativeMaterial is implemented to take into account the heat exchange between the boundary of a mesh and the surrounding atmosphere (at uniform Temperature) without taking into account any view factor or self exchange between mesh.

the heatFlux (W/m² / mW/mm²) is equal to $flux = -\sigma \epsilon (T^4-T_{amb}^4)$ with :

$sigma$ : the Boltzmann Constant (5.67 × 10-8 W/m²K4)
$\epsilon$ : relative emissivity parameter (1)
$T$ : temperature at the integration point (K)
$T_{amb} : Room temperature (K)

It is design to work with Tm(2)Boundary2D(/3D)Element. By default, the surrounding model has to be defined in Kelvin, but defining the parameter RAY_CELSIUS to True allows using it in a Celsius defined test.

'''
mat = materset.define(no, RadiativeMaterial )
mat .put(param1, value1)
mat .depend(param1, fct1, Lock1)) #optional
...

where

`param1`	name of the property associated to the element (for example `RAY_EMISSIVITY`
`value1`	value of the corresponding property
`fct1`	function which characterizes the dependency of the property (optional: no fct if no dependency)
`Lock1`	Lock which defines the dependency variable of the property (compulsory if there is a dependency)

Parameters

Name	Description	Dependency
`BOLTZMANN_CST`	Boltzmann Constant (required to set units) = $ 5.67e^{-8} W/m^2K^4 $ = $ 5.67e^{-11} mW/mm^2K^4$	Set
`RAY_EMISSIVITY`	Relative emissivity between two gray bodies (solid / room) $\epsilon = \frac{\epsilon_1 * \epsilon_2}{\epsilon_1 + \epsilon_2 - \epsilon_1 * \epsilon_2}$	time
`RAY_TEMP_AMB`	Room temperature (K)	time
`RAY_CELSIUS`	flag to chose Themperature unit system of the test (default : Kevin ⇒ False)	-