MAT4

Bulk Data Entry Defines constant thermal material properties for conductivity, density, and heat generation.

Format

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MAT4 MID K CP RHO H   HGEN    

Example

(1) (2) (3) (4) (5) (6) (7) (8) (9) (10)
MAT4 24 200   2e5          

Definitions

Field Contents SI Unit Example
MID Unique material identification.
Integer
Specifies an identification number for this material.
<String>
Specifies a user-defined string label for this material entry. 2

No default (Integer > 0 or <String>)

 
K Thermal conductivity.

Default = 0.0 (Real ≥ 0.0)

 
CP Heat capacity per unit mass (specific heat). 4

(Real ≥ 0.0 or blank)

 
RHO Density. 4

Default = 1.0 (Real > 0.0)

 
H Free convection heat transfer coefficient.

Default = 0.0 (Real)

 
HGEN Heat generation capability used with QVOL entries. HGEN is the scale factor used with QVOL.

HGEN is the scale factor and QVOL is the power generated per unit volume, Pin = volume * HGEN * QVOL.

Default = 1.0 (Real ≥ 0.0)

 

Comments

  1. The material identification number/string may be the shared with structural material property definitions (MAT1, MAT2, MAT8, MAT9 or MGASK) but must be unique with respect to other thermal material property definitions (MAT4 or MAT5).
  2. String based labels allow for easier visual identification of materials, including when being referenced by other cards. (example, the MID field of properties). For more details, refer to String Label Based Input File in the Bulk Data Input File.
  3. MAT4 may specify material properties for any conduction elements. MAT4 also provides the heat transfer coefficient for free convection (CONV).
  4. Heat capacity (CP) is defined per unit mass. It is multiplied by density (RHO) to calculate heat capacity matrix in transient heat transfer analysis. If RHO is not defined on MAT4, then positive density from a structural material entry with matching MID is used. If MAT4 does not have a corresponding matching structural material, then the default value of 1.0 is used.
  5. This card is represented as a material in HyperMesh.