Discussion Groups

Simulation Moldflow Insight

Reply
Active Member
andreeccel
Posts: 10
Registered: ‎10-21-2011

Cool analysis

165 Views, 4 Replies
04-11-2012 06:44 AM

Hello,

 

I'm having a small problem in one of my studies here.

When I increase the mold temperature (maintaining all the other variables constants) , the cycle time descreases.

But it should have increased too, because the heat loss flux decreases when the deltaT is lower.

Well, this is happenning in both meshes, Dual Domain and 3D.

Does anyone have ever seen something like that?

 

Thanks,

 

André Eccel Vellwock

Please use plain text.
Valued Contributor
HugoHerrera7042
Posts: 62
Registered: ‎07-07-2009

Re: Cool analysis

04-11-2012 08:22 AM in reply to: andreeccel

interesting

i'm assuming you have the waterline system and the cycle time is set as automatic at a certain frozen % and ejection temperature.

 

from my understanding, when you are running a cooling analysis, the mold surace temperature becomes the target temperature...

 

since you are increasing the mold surface target temperature, i would look into my water inlet temperature. is it the same as before?

 

this means the cooling analysis is looking to reach the mold surface temperature you specified, and if it is hotter, I guess it is obvious that it will be reached in a shorter period of time....does this make any sense? in other words, you are telling the model to tell you how much time would it take to eject the part out of the mold at a hotter mold surface temperature...

 

question: does the time to reach ejection temperature from the flow analysis matches the 'time to reach ejection temperature part' from cooling analysis?

Please use plain text.
Active Member
andreeccel
Posts: 10
Registered: ‎10-21-2011

Re: Cool analysis

04-11-2012 09:46 AM in reply to: HugoHerrera7042

The model with the hotter mold temperature, also the higher the rise of the coolant inlet temperature. But I think that its not obvious that the hotter, the faster to reach the the target mold temperature, because the heat flux would be lower, thus the time would be higher.

Please use plain text.
Active Member
andreeccel
Posts: 10
Registered: ‎10-21-2011

Re: Cool analysis

04-11-2012 10:01 AM in reply to: andreeccel

question: does the time to reach ejection temperature from the flow analysis matches the 'time to reach ejection temperature part' from cooling analysis?

 

answer: No, it doesnt match.

Please use plain text.
Valued Contributor
abakharev
Posts: 62
Registered: ‎08-25-2008

Re: Cool analysis

04-11-2012 07:39 PM in reply to: andreeccel

According to the help for the cooling analysis file:

 

Automatic analysis

An automatic analysis adjusts processing parameters to optimize the cooling time required to achieve a target average mold temperature specified in the Process Settings Wizard and the specified percentage freeze level in the plastic part.

The automatic analysis calculates the cycle time based on two parameters:
  • Achieving a target mold temperature within 1ºC.
  • The percentage of the part that is frozen. 

The higher the target mold temperature the less cooling time is sufficient to achieve the target . Thus, the observed effect. Obviously, someone can achieve the target mold temperature faster if increase the water flow rate in the cooling channels or make them thicker or longer or closer to the cavity, etc...

 

If you are trying to optimize the mold temperature to achieve the best moldings outcomes (including cooling time) I would first start with flow or flow+warp, get the optimal mold temperature, then play with the cooling achieving the required mold temperature in a given cycle time.

Please use plain text.