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[congmin]

The heat generated by maxwell is opposite to the temperature distribution curve





strange



Going out specific heat capacity convection conditions and other issues, making them contrary, is it possible that I have made a mistake in setting the conditions in the steady state thermal module operation

If so, can you tell me, what are the possible conditions? 
Thanks

[Karthik R]

Hello,

What do you mean by the direction being the opposite? Do you mean that the thermal energy should leave your computational domain (as opposed to entering it)? 

I'm not able to make out much from the images you have posted. Could you please post clearer images here so we can take a look and better understand the issue?

Thank you.

Karthik

[congmin]

Hi,Kremella

 

 

First of all thank you for answering me

The imported heat density from Maxwell to steady state thermal is shown in picture 1.
 
It should be that the calorific value on both sides of the board is small, and there are two maximum values in the middle part, but the calorific value in the middle part is less than the two maximum worth points,in picture 2

The distribution should be the almost same as the imported thermal density distribution curve, as shown in picture 3

but the actual result of the steady-state thermal simulation is that the temperature in the middle of the board has not decreased. As
 
 
shown in Picture 4
 
 

what wrong operation of the steady-state thermal module will cause this this results of it?
 
Thanks
 




 

[congmin]

First of all thank you for answering me

The imported heat density from Maxwell to steady state thermal is shown in picture 1

calorific value on both sides of the board is small, and there are two maximum values in the middle part, but the calorific value in the middle part is less than the two maximum worth points,in picture 2 

The distribution should be the almost same as the imported thermal density distribution curve, as shown in picture 3 

the steady-state thermal simulation is that the temperature in the middle of the board has not decreased. As     shown in Picture 4

 

what wrong operation of the steady-state thermal module will cause this this results of it?   Thanks  

 

 

[Karthik R]

Hello,

Even though there is a heat flux difference between the center and the location where you are seeing the maximum, since you are looking at a steady-state temperature profile, it seems to me that you could be getting the correct answer along the line you are plotting. This could be because the difference in the heat flux is small between the location where you are seeing the maximum value and the center of your board.

One way you could verify - If you run a transient simulation, you might see a temperature plot similar to your hand-sketch (especially in the beginning). If you run this transient simulation longer, you should see the same temperature plot that your steady state model is currently showing.

I hope this helps.

Best,

Karthik

[congmin]

Hi Kremella

 

Thank you for your answer.I will try to  run this transient simulation .Thank you so much!!!!!

best

Congmin

[Karthik R]

Excellent! If this answered your question, please mark the appropriate answer as 'Is Solution'. This might benefit others on the community.

Thank you.

Karthik

[congmin]

In the steady-state thermal module, the result is that the workpiece is heated to about 900  celsius. I then went to the transient thermal module to analyze and found that after 900 celsius, the workpiece still heats up. Where does the problem cause this?

[Karthik R]

What do you mean by the heating up of the workpiece? Could you please elaborate?

Thanks.

Karthik

[congmin]

hey

The setting conditions of the steady-state heat and the transient heat are the same. The transient heat is set for 1000 seconds. Check the temperature curve. The transient heat is simulated to about 600 seconds. The workpiece temperature almost reaches the temperature curve of the steady-state heat. Logically, the simulation should be in It stops at about 600 seconds, but the fact is that the temperature of the workpiece keeps rising to 1100 celsius from 600 to 100 seconds. What problem is causing this error

Thank you

congmin

[Karthik R]

I know you are applying the heat flux from your Maxwell run. What other boundary conditions are you applying here?

Is this not your steady-state temperature result? From this plot, it seems like you are getting steady temperatures ~ 1100 degC? Is this not the case?

Thanks.

Karthik

[congmin]

Sorry, this picture is 1100 degrees Celsius I used to draw the current of 70A

 

When I do the transient thermal simulation, I use a current of 65A, so the steady-state temperature curve is about 900 degrees Celsius

 

Transient simulation for 1000 seconds, but 600 seconds has been 900 degrees Celsius, but 600-1000 seconds, the temperature will continue to rise, reaching 1000 degrees Celsius in 1000 seconds. I don't understand, why is it that the steady-state temperature is exceeded and the simulation will continue for a long time after 600 seconds, where is the problem caused?

 

thanks 

congmin

[Karthik R]

Can you please share some screenshots of your transient simulation in Transient Thermal?

Thanks.

Karthik

[congmin]

hi Karthik

Sorry I reply too late, because the computer is simulating other projects before, and I cannot open the transient thermal project

 

I just checked out the problem. My convection heat transfer coefficient was accidentally entered incorrectly. The heat transfer coefficient is different from that in steady-state heat, so this problem

 

The problem has been solved, and as you said, in the transient heat, the initial curve is the same as I imagined. After 20 seconds, the temperature curve is similar to the steady state thermal curve.

 

 

Thank you very much for your patience to answer

congmin

[Karthik R]

Perfect! Good to know!

[congmin]

hi Karthik

 

I now want to set the thermal emissivity of 22MnB5, but I found that I can only fill in a constant value, but the thermal emissivity changes with temperature, so I want to fill in an emissivity table. Is this possible? If so, can you take a screenshot and teach me how to do it?

 

thanks !!!!

congmin

[Karthik R]

Hello,

Please create a new post for any new question that you might have and we will be happy to help. This will greatly help others on the community.

Thanks.

Karthik

[congmin]

hello,karthik

 

https://forum.ansys.com/forums/topic/emissivity-setting-in-constant-form-in-steady-state-thermal-module/

this is new question link

 

thanks 

congmin

[congmin]

 

 

hello,karthik

 

 

 

I have another question about maxwell import loss value to steady state module

 

maxwell cannot be transferred to steady-state heat. The heat density of the steady-state thermal module is not the same as the loss value in maxwell. Ask what, what should I do

 

 can you answer me?

https://forum.ansys.com/forums/topic/maxwel-loss-imported-value-to-steady-state-thermal/

 

 

thanks 

 

congmin