Baffles - Circuit heat removal efficiency result

[teopado89]

Hi everyone, i have this problem:

i run a cool+fill+pack+warp analysis using ASMS2014.

My prodecure it always the same:

i receive a solid geometry of the cooling system from mold designer, i creates lines to simulate che circuit.

I import this IGES file into moldflow, i assing the property of channel (10mm diameter) and baffles (18mm diameter).

I mesh them.

I check connectivity of all the circuit.

I add inlets (5 degrees lower than mold temperature)

I set mold open time and cycle time.

Run the analysis.

Today looking at the result "Circuit heat removal efficiency result" i found strange things:

1) almost all the circuit has a value of zero (0.02) so it's quite useless because it doesn't extract heat, and in some channel it's also "-1" so it's giving heat to the mold.

2) the baffle changes a bit color but "in the wrong direction", i mean Moldflow says there is more extraction of heat (very low value, 0.1) in the part of the baffle far away from the plastic, and in the same baffle the closest part to the plastic extracts less heat (0.02), and it doesn't make sense.

3) Also i set the inlet at 80 degrees, and all the circuit never exceeds this temperature, and i think it's impossible because water in a mold at 5 degrees higher temperature (and with hot plastic inside) should rise its temperature.

I was thinking the cooling circuit war oversized (and for this reason it didn't extract heat), but also deleting almost half of the entire cooling circuit, the result doesn't change.

The only difference compared to my usual analysis was that today i inserted two plastic inserts (because the part is a three shots rear lamp) and the 3d mesh represents the last shot.

For this reason i tried to delete the two inserts and i run a cool+fill+pack+warp analysis with the same cooling circuit and only the mesh of the last shot, it's sequential gate (only the gate, not the full runner system). This last analysis it's equal to the previous one, just without the 2 inserts.

BUT the Circuit heat removal efficiency result is the same.

May you help me please?

Thanks

[teopado89 · Accepted solution]

Hi everyone, 

my local support answered:

it could be a right result, it depends of the mold temperature.

If it's high the cooling circuit removes heat, viceversa it gives heat, because it's main purpose is to keep temperature and reduce variations.

He told me the most important result to look at is the mold temperature, the more uniform, the better.

Also about variations of temperature in the cooling circuit, they can be very content (also less than 0.5 degrees).

Bye