====== LBLZT ======
===== Description =====
Thermal conduction constitutive law for solid elements at constant temperature (only suited for [[elements:blz2t|BLZ2T]] and [[elements:blz3t|BLZ3T]]).
==== The model ====
This law is only  used for non linear thermal analysis of isotropic solids.
This constitutive law takes account of heat transfer by conduction and heat accumulation in solids, the conductivity and heat capacity of which depend on temperature. This law is used for two or three dimensional heat flow.

==== Files ====
Prepro: LBLZT.F \\
===== Availability =====
|Plane stress state| YES |
|Plane strain state| YES |
|Axisymmetric state| YES |
|3D state| YES |
|Generalized plane state| NO |
===== Input file =====
==== Parameters defining the type of constitutive law ====
^ Line 1 (2I5, 60A1)^^
|IL|Law number|
|ITYPE| 105 |
|COMMENT| Any comment (up to 60 characters) that will be reproduced on the output listing|
==== Real parameters ====
^ Line 1 (5G10.0 ) ^^
|RHOC|heat capacity per unit volume|
|ALAMB1|heat conductivity at direction 1|
|ALAMB2|heat conductivity at direction 2|
|ALAMB3|heat conductivity at direction 3|
|ALFA|coefficient of temperature effect \\  NB: $\vec{q} = \lambda (1-\alpha T) \vec{grad}(T)$|
===== Stresses =====
==== Number of stresses ====
= 4 (for the 2-D state) \\ 
= 5 (for the 3-D state)
==== Meaning ====
__For the 3-D state__
|SIG(1)|conductive heat flow in the X direction $(=q_X)$|
|SIG(2)|conductive heat flow in the Y direction $(=q_Y)$|
|SIG(3)|conductive heat flow in the Z direction $(=q_Z)$|
|SIG(4)|energy accumulated by heat capacity|
|SIG(5)|heat power generated by plastic strains in case of coupled thermo-mechanical analysis.|

__For the other cases__
|SIG(1)|conductive heat flow in the X direction $(=q_X)$|
|SIG(2)|conductive heat flow in the Y direction $(=q_Y)$|
|SIG(3)|energy accumulated by heat capacity|
|SIG(4)|heat power generated by plastic strains in case of coupled thermo-mechanical analysis.|