Temperature, runner (transient from start-up) result

The Temperature, runner (transient from start-up) result is a Dual Domain result that shows the temperature of the runner as it changes with time, from the beginning of the first start-up cycle until the mold temperature stabilizes.

This result is based on the transient mold surface temperature, which includes the clamp open time. It is calculated by averaging all the laminate temperature results through the thickness of the runner for each time step and plotting them on the surface of the runner. The temperature laminate results are calculated using a finite difference method through the thickness of the runner.

This calculation takes into account the Mold-melt Heat Transfer Coefficients (HTC) values, which you can set on the Mesh tab of the Solver parameters dialog, in the Advanced options of the Process Settings.

Tip: The lower the HTC value, the greater the resistance to heat transfer between the polymer and the mold.

Using this result

Use this result to find localized hot or cold spots, and determine whether they will affect cycle time and part warpage. If there are hot or cool spots, you may need to adjust the cooling channels. Use a cutting plane to investigate hot or cold spots inside the part.

The difference between the temperature across the top or bottom face of the part and the target mold temperature should not be greater than ±10°C.

The runner temperature can be studied more closely by reducing the temperature range. To do this, click on (Home tab > Results panel > Results), selecting (Scaling pane > Set Scale) and decrease the value in the Max box.

Note: If you animate the result, it will show you how the temperature changed over the duration of the analysis inside the solid model.

Tip: You can create an XY plot of the transient runner temperature, on any given node to see how the temperature at that node varies with time. Click on Results in the Results pane of the Home tab, then click (New Plot > Plot) and scroll down to the result. Remember to change the Plot type to XY plot.

Things to look for

When viewing the Temperature, runner (transient from start-up) result, watch for the following.

• Regions that freeze off early. The gate should not freeze before the part.
• Hot and cold regions.
• The cooling pattern. Is it evenly distributed?