Time to reach ejection temperature, part result (Cool analysis)

The Time to reach ejection temperature, part result that is produced by a Cool analysis shows the time required to reach the ejection temperature, which is measured from the start of the cycle.

At the start of the measurement, the part is assumed to be filled with material at its melt temperature (Tmelt).

The Time to reach ejection temperature is calculated on the mold wall temperature. If a part of the mold wall is above the ejection temperature (Teject) at the end of the cycle time provided, then, for a Dual Domain analysis, a warning is posted in the Analysis Log.

To avoid receiving a warning, the following steps can be taken.

Increase the cycle time, to obtain more time for cooling.
If you have already designed a cooling circuit, lower the temperature of the coolants.
Place a cooling circuit in the area where the elements are not freezing

Using this result

Ideally the part should freeze uniformly. Areas of the part that take longer to freeze may indicate hot spots, or thicker cross sections.

Look at the time difference between most of the model freezing and the last area freezing. If this difference is large, determine if the problem is caused by an increased wall thickness or a high mold temperature. If the thickness is high, consider redesigning the part. If the mold temperature is high, modify the cooling layout to eradicate the hot spots.

You can also use the Time to reach ejection temperature, part result in conjunction with the Cooling time variance result to diagnose non-uniform cooling.

This result will help you design a cooling layout for a detailed analysis of part cooling using the Cool analysis. The Time to reach ejection temperature, part result will then provide you with the suggested corrective action.

Things to look for

When viewing the Time to reach ejection temperature, part result, watch for the following:

Uniform polymer freeze distribution.
Check the Circuit Reynolds number result to ensure that the Reynolds number values for each circuit are high; low values indicate inefficient heat extraction. Increase the flow rate into the relevant circuit(s).
Hot spots-try to achieve more uniform cooling.