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# NO conduction between elements in a body

## NO conduction between elements in a body

(OP)
Hello, I am working with Mechanical APDL, I have built a body, meshed it and filled the volume with solid70 elements.

I have defined thermal loads and calculated a transient analysis where the heat source moves along the workpiece.
The problem is that it seems that olnly the first layer of elements (in which the thermal load is applied) is being affected by the heat.
The next layer of elements has only the TUNIF temperature. Consideing that temperatures over 300ºC are being reached in the first layer I assume that 0.5mm deeper in the workpiece the temperature should be higher than 20ºC.

This is an image of the fist step but the conduction in the z axis is the same all over the analysis.

In the z axis is where I notice the heat is not being conducted. It could also be happening that heat is not being conducted along the XY plane.

I believe that the problem is that elements are not conducting heat to each other but i cant find the problem.

I didn't specifically defined the conduction in the model so this could be the problem.

I say this as a tip to try to solve the problem.

Thanks!!

### RE: NO conduction between elements in a body

(OP)
Hello again.
I have created a simpler model to see if i made any mistakes in the way and the result is the same.
As yuou can see the temperatura stays at 20ºC once you have passed the first layer of elements. I will put two pictures of the model since i dont know how to plot the nodal temperatura and the element grid at the same time.

This is the nodal temperatura in Time=5s

This is the element grid

Also, i write the full program for this rectangle. The program for the image in the first post was too long.

FINISH
/CLEAR
/PREP7

K,1,0,0,0
K,2,100,0,0
K,3,100,50,0
K,4,0,50,0

L,1,2
L,2,3
L,3,4
L,4,1

A,1,2,3,4

MPTGEN,1,10,20,100
MPDATA,KXX,1,1,48,43,40,38,36,34
MPDATA,KXX,1,7,31,27,26,25
!c es el calor especifico, unidades J/Kg*K
MPDATA,C,1,1,500,525,550,600,650,750
MPDATA,C,1,7,800,1250,700,650
MP,DENS,1,7850

!flujo de calor en W/mm^2
qf=50000000

LESIZE,1,,,50,1,,,,1
LESIZE,2,,,25,1,,,,1
LESIZE,3,,,50,1,,,,1
LESIZE,4,,,25,1,,,,1

ET,1,SOLID70

ALLSEL,ALL

ASEL,S,LOC,Z,0
VEXT,ALL,0,0,0,0,2,1,1,1

ASEL,S,LOC,Z,2
VEXT,ALL,0,0,0,0,2,1,1,1

ASEL,S,LOC,Z,4
VEXT,ALL,0,0,0,0,2,1,1,1

ASEL,S,LOC,Z,6
VEXT,ALL,0,0,0,0,2,1,1,1

ASEL,S,LOC,Z,8
VEXT,ALL,0,0,0,0,2,1,1,1

MAT,1
TYPE,1
VMESH,ALL
NUMMRG,NODE

t_sim=5

t_step=0.5

pasos=t_sim/t_step

FINISH
/SOLU

*SET,t_actual,t_step

!tipo de analisis [transitorio]
ANTYPE,4

!tipo de analisis transitorio [completo]
TRNOPT,FULL

!tipo de solver [newton-raphson completo]
NROPT,FULL

!definir la temperatura inicial de todos los nodos a 20º
TUNIF,20

KBC,1

!aumentar el numero maximo de iteraciones. normalmente usado para problemas no luineales
NEQIT,30

*DO,ii,1,pasos

NSEL,ALL
NSEL,S,LOC,Y,50
NSEL,R,LOC,X,10,20

SF,ALL,HFLUX,qf

ALLSEL,ALL

TIME,t_actual

AUTOTS,0

NSUBST,2,2,2

SAVE
SOLVE

RESCONTROL,NORESTART,NONE

*SET,t_actual,t_actual+t_step

*ENDDO

### RE: NO conduction between elements in a body

Check the units you use. I think you have used dimensions in mm and properties in metres.

### RE: NO conduction between elements in a body

(OP)
I think i found the problema.
I have done the VMESH after the VGLUE and it worked, i got to extend the heat along more elements tan the ones in the first line.
I have to check the units too but i think the main problema was this i just wrote. In the script avobe the VGLUE function was not activated but i think this also must be done.

Greetings!

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