Temperature, runner (transient) result

The Temperature, runner (transient) result is a Dual Domain result that shows the average temperature across the thickness of the runner, calculated at each time step of the cycle.

This result is based on the transient mold surface temperature at each step of the cycle. 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

You should expect to see that thicker regions of the runner are hotter than the thinner sections of the runner or gate. The cooling solver does not take shear heating into account hence the thinner sections, such as gates, should not be hotter than thicker sections. This result shows the time taken for the average temperature to reach a given value, such as ejection time or freeze time. This result can also be used to find the ideal position of cooling channels, since the effect of the cooling channel position in relation to a runner can be seen.

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 runner temperature on any given node to see how the temperature at that node varies with time. To do this, click (Home tab > Results panel > Results), 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) result, watch for the following.

• Check that the average temperature is well below the ejection temperature for the material at the end of cooling, so that the part can be ejected successfully.
• Look out for problems with smaller runner sections cooling too fast.
• Check that the gate is not freezing too quickly