Card 9 - MAT Material Property Definition

This optional card defines the material properties of Card 5 elements. If a property is not defined, the default values apply.

Parameters: KODE, N1, keyword, value

KODE

KODE is the code MAT (or 32)

N1

N1 is the material number.

keyword

keyword is the keyword for the property specified.


Keyword	Description
`ABLAT`	If value is ≠ 0, then the material can ablate. Only multilayer shells and solids can abHTLAT late. TPHASE and must be specified for ablative materials. If 1>ABLAT>0, (e.g. .5) then the material ablates, i.e. burns up during phase change. For homogeneous multilayer shells, once a shell layer has ablated, its conductance to adjacent layers is increased by a factor of 100,000, and its in-plane conductance and capacitance are set to 1.E-6 times its value. Similarly, once a solid element has ablated, its thermal conductivity is increased by a factor of 100,000, and its thermal capacitance is set to 1.E-6 times its value. If value >1 and value is an integer, it is interpreted to be the material ID for the ablated phase. For this case charring is assumed to occur during ablation, and the material properties of the charred material are defined by value. A set of MAT Cards with material `ID = value` must be present for this option.
`ABSORPTIVITY`	Surface absorptivity in solar spectrum.
`CAPAPH`	Specific heat above phase change temperature, may not be table-dependent. To specify a table-dependent specific heat above the phase change temperature, specify the specific heat to be table-dependent.
`COEFFTHERM`	Thermal expansion coefficient of the material. Not used.
`CONVAR`	Specified variable that check for material conversion. The keyword is TEMP.
`CONVTO`	Enables properties with material ID = N1 to convert to properties with material ID = value.
`CONVTH`	Specified threshold value of the conversion variable.
`CPP`	Specific heat value at constant pressure. The nominal value for air in SI units is 1007 Nm/ Kg/ °C. For water it is 4187 Nm/Kg/C. For aluminum it is 1088 Nm /Kg /°C, and for steel 669 Nm/ Kg/ °C.
`E`	Emissivity E may be replaced by the keyword NORAD (or -2.34) for materials that do not radiate.
`ELECRES`	Electrical resistivity of material. Default is 0.
`RSPECIFIC`	Specific gas constant of material.
`HTLAT`	Latent heat per unit mass at phase change temperature.
`IRSPEC`	Surface specularity in the IR spectrum.
`IRTRANS`	Surface transmissivity in the IR spectrum.
`IREXTINCT`	IR spectrum extinction coefficient. If this property is specified for a solid element, then during ray tracing calculations the IR spectrum strength of each ray traveling through the element is diminished by a fraction equal to: where `LENGTH` is the length of the path of the ray through the element. `IREXTINCT` is ignored for shell, beam or lump mass elements. If a non-zero IREXTINCT or SOLAREXTINCT property is specified for a solid element, it is automatically surface coated with transparent shell elements with reverse sides. The reduction in the value of the ray strength is considered to be due to absorption by the solid. The power absorbed in the solid element is assigned to the surface coated shell elements, rather than to the solid element itself.
`IREFFRONT`	Index of refraction on the front surface of a transparent material for both the IR and solar spectra. If IREFFRONT is not specified, or is specified to be zero, it defaults to 1. For shell elements, IREFFRONT is the index of refraction on the front surface, and IREFBACK on the reverse side. The bending of a light going through the element ray and incident on the front surface a transparent element is calculated with Snell’s Law: where thtafront is the angle between the incident ray and the surface normal thetaback is the angle between the transmitted ray and the surface normal If sin(thetaback) > 1, transmission is not possible, and full reflection occurs. Each surface of solid elements with IREFFRONT>1 is automatically surface coated with two transparent shell elements: one facing the element, and one facing away. The index of refraction of the element facing the solid is assigned the value of IREFFRONT, and its reverse side is assigned the IREFFRONT value of the adjacent element. The IREFBACK value is ignored for solid elements. If there is no adjacent solid element, or the adjacent solid element does not have an index of refraction value specified, then it is assumed to be a free surface, and the reverse side is assigned an index of refraction value of unity. If the index of refraction through a solid is not uniform, a curved path is calculated for a ray traveling through the solid.
`IREFBACK`	Index of refraction on the back surface of a transparent material. If IREFBACK is not specified or is set to 0, it defaults to IREFFRONT. IREFBACK is ignored for solid elements.
`IRSCATTER`	Specifies the infrared spectrum scattering coefficient in a semi-transparent material. This is also sometimes referred to as the infrared spectrum macroscopic scattering cross section. The units of the scattering coefficient are length^-1. Used only with Monte Carlo ray tracing.
`IRREDIFF`	Infrared diffuse reflectivity. This value is only used when Monte Carlo ray tracing is to be performed and a BRDF table is to be specified for the bidirectional reflectivity of the material. The value should point to a table number.
`KTHERM`	Thermal conductivity.A nominal value for air in SI units is .0263 W /m/ °C. For water it is .603 W /m/ °C, for pure aluminum 249 W /m/°C, for steel 31 W /m/ °C.
`KXX`	Orthotropic or anisotropic thermal conductivity in the material X direction, which is defined on MATVEC Cards. For each orthotropic element the material's orientation vectors must be defined on a corresponding MATVEC Card.
`KYY`	Orthotropic or anisotropic thermal conductivity in the material Y direction, which is defined on MATVEC Cards.
`KZZ`	Orthotropic or anisotropic thermal conductivity in the material Z direction, which is defined on MATVEC Cards.
`KXY`	Anisotropic thermal conductivity in the material XY direction.
`KXZ`	Anisotropic thermal conductivity in the material XZ direction.
`KYZ`	Anisotropic thermal conductivity in the material YZ direction.
`PHASE`	Property describing phase of a material. May be SOLID, LIQUID, GAS, or DAMAGE. Option DAMAGE flags the material as damage interface material and is only valid for cohesive elements. The solver treats damage interface elements by assuming perfect contacts between their upper and lower faces, ignoring their other properties.
`POISSONRATIO`	Poisson's ratio for an isotropic material.
`POISSONRATIO12` `POISSONRATIO23` `POISSONRATIO13`	Poisson's ratio for an orthotropic material.
`REMISS`	Emissivity of the reverse side of an element. Default value is –2.34. If REMISS≥0 is specified, reverse side elements will be automatically created for all the elements of this MAT Card similarly to the Card 9 REVNODE Card `T1 = 0` option, where the reverse and front sides are automatically merged, and the element numbers of the reverse sides are automatically assigned. In case of conflict with a reverse side specified on an existing REVNODE or REVNOM Card, the REVNODE or REVNOM Card definition will prevail.
`RABSORP`	Absorptivity of reverse side of element. Default value is –2.34.
`RSOLSPEC`	Solar spectrum specularity on reverse side of element Default value is 0.
`RIRSPEC`	IR spectrum specularity on reverse side of element. Default value is 0.
`RHO`	Density. For hydraulic elements, this is the density of the fluid at the standard temperature and pressure defined on the HYDENV Card. The nominal value for air in SI units is 1.207 Kg/m³ at a pressure of 101,351 Newtons/m² and temperature of 20 °C. For water it is 1000 Kg/m³. For aluminum it is 2,700 Kg/m³, and for steel 7,850 Kg/m³. If the density of a hydraulic element is table-dependent, its PHASE value should be flagged as LIQUID. The thermal solver supports only constant density for SOLID elements. If the density of a `SOLID` element is provided by a temperature-dependent mass density table, the density at the interpolation temperature is computed using the following Card: `GPARAM 1 335 T2` where T2 is the user-defined interpolation temperature in Kelvin.
`SATRHO`	Saturation density of fluid. Used for CFD calculations only, e.g. when the saturation density of water is specified as a function of temperature for condensation analysis.
`SOLAREXTINCT`	Solar spectrum extinction coefficient. If this property is specified for a solid element, then during ray tracing calculations the solar spectrum strength of each ray traveling through the element is diminished by a fraction equal to: where `LENGTH` is the length of the path of the ray through the element. `SOLAREXTINCT` is ignored for shell, beam or lump mass elements. If a non-zero `IREXTINCT` or `SOLAREXTINCT` property is specified for a solid element, it is automatically surface coated with transparent shell elements with reverse sides. The reduction in the value of the ray strength is considered to be due to absorption by the solid. The power absorbed in the solid element is assigned to the surface coated shell elements, rather than to the solid element itself.
`SOLARSCATTER`	Specifies the solar spectrum scattering coefficient in a semi-transparent material. This is also sometimes referred to as the solar spectrum macroscopic scattering cross section. The units of the scattering coefficient are length^-1. Only used when Monte Carlo ray tracing is to be performed.
`SOLREDIFF`	Solar diffuse reflectivity. This value is only used when Monte Carlo ray tracing is to be performed and a BRDF table is to be specified for the bidirectional reflectivity of the material. The value should point to a table number.
`SPECULARITY`	Surface specularity in solar spectrum.
`TPHASE`	Phase change temperature for phase change material.
`TPHASERANGE`	Specifies the range of temperature ΔT over which the phase change occurs. where T1 is the low end of the temperature range ΔT is the temperature range T2 is the high end of the temperature range T1 must be specified in the TPHASE card.
`TRANSMISS`	Surface transmissivity in solar spectrum.
`VISC`	Dynamic viscosity for 1-node hydraulic elements only. A nominal value for air in SI units is 1.85E-5 Nsec/m², for water .001 Nsec/m². Default = 0.
`YOUNGMODULUS`	Young's modulus for an isotropic material.
`YOUNGMODULUS1` `YOUNGMODULUS2` `YOUNGMODULUS3`	Young's modulus for an orthotropic material.

value

value is the specified value for the material property. If not specified, the default values are zero, except for the following:


Keyword	Default value
`E`	`NORAD` (or -2.34)
`PHASE`	`SOLID` (or 1)
`TPHASE`	1.E6

If material is table or array dependent, for example its properties are described in table n, then value may be the mnemonic Tn (e.g. T210 for table or array 210).

Code example

$ CARD 5
101 SURFACE M2 0 P4 1 2 3 4
$ ELEMENT 101  HAS PROPERTIES DEFINED WITH MAT CARD 2
$ AND PROP CARD 4
|
$ CARD 9
PROP 4 PLANAR 1.6
$ ELEMENTS WHICH REFERENCE PROP CARD 4 HAVE
$ A THICKNESS OF 1.6
$
MAT 2 RHO 2.6
MAT 2 CPP 7.8
MAT 2 E .6
MAT 2 ABSORPTIVITY .4
MAT 2 KTHERM 1.4
$ ELEMENTS WHICH $REFERENCE MAT CARD 2 HAVE
$ DENSITY=2.6, SP. HEAT=7.8, EMISSIVITY=.6,
$ ABSORPTIVITY=.4 AND THERMAL CONDUCTIVITY = 1.4
$
MAT 3 KTHERM T2
TABTYPE 2 KTHERM TEMP
TABDATA 2 .6 -100
TABDATA 2 .5 0
TABDATA 2 .5 100
$ THERMAL CONDUCTIVITY OF MATERIAL 3 IS
$ TEMP. DEPENDENT, DEFINED ON TABLE 2
$
$  This example shows infrared and solar diffuse reflectivity pointing to the
$  same BRDF table.
$
MAT 1 IRREDIF T002
MAT 1 SOLREDI T002
ARRAYTYPE 2 ANG_INC ANG_REF BRDF
ARRAYDATA 2   0.0   0.0  0.8
ARRAYDATA 2   0.0  44.9  0.8
ARRAYDATA 2   0.0  45.0  0.0
ARRAYDATA 2   0.0  90.0  0.0
$
ARRAYDATA 2  44.9   0.0  0.8
ARRAYDATA 2  44.9  44.9  0.8
ARRAYDATA 2  44.9  45.0  0.0
ARRAYDATA 2  44.9  90.0  0.0
$
ARRAYDATA 2  45.0   0.0  0.0
ARRAYDATA 2  45.0  44.9  0.0
ARRAYDATA 2  45.0  45.0  0.8
ARRAYDATA 2  45.0  90.0  0.8

Notes

If material is table or array dependent, for example its properties are described in table n, then value may be the mnemonic Tn (e.g. T210 for table or array 210). For multispectral runs, the IR spectrum properties only (E, IRSPEC, etc.) may be defined to be spectrum-dependent, where the dependent variable on the TABTYPE Card is WAVELENGTH. Within the same run, radiative properties may be defined to have constant IR and solar properties, or be wavelength dependent. TMG will automatically create the appropriate wavelength-dependent tables from IR and solar properties for multispectral runs where necessary, and the appropriate constant solar and IR properties from spectrum-dependent properties for non-multispectral runs. For more information, see Card 9 - PARAM Parameter Card - Optional.

Note for each MAT Card N1 the 7-character group name _M0000N1 (e.g. _M00016 for MAT Card 16) is automatically created.