Cooling Analysis Strategies

Cooling Analysis ObjectivesCooling Analysis Objectives

Cooling analyses are performed to determine (in part) Cooling line placement Minimum cycle time Minimum temperature distribution on cavity and/or core Minimum temperature distribution between cavity and

core Whether high thermal conductivity inserts should be

used

Analysis TypeAnalysis Type

Objectives determines are cooling analyses are run There are two analysis types

Manual analysis• A cycle time is input into the analysis• Best if there is a known cycle time• Best if the cooling layout is poor

Automatic analysis• Calculates the cycle time for you• Best for minimizing cycle time• Automatic analysis should not be run if the cooling layout

is poor, because cycle times will be extended.

Automatic AnalysisAutomatic Analysis

Cycle time is calculated by Making sure the part is 100% frozen

• 100% frozen is the default, but the value can be defined Average of mold surface temperatures (top and

bottom) for all elements is within 1°C of the target mold temperature

Mold temperature convergence tolerance Maximum number of mold temperature iterations Geometric influence

Analysis Advanced ParametersAnalysis Advanced Parameters

Geometry Influence Parameter (GIP)Geometry Influence Parameter (GIP)

Geometric influence option Automatic

• The software calculates the minimum number of surrounding elements required to produce accurate cooling results for each element, which is faster and requires less computing time.

Ideal• The calculation for each element takes

into account all other elements in the model

Automatic

Ideal

Geometry Influence Parameter (GIP)Geometry Influence Parameter (GIP)

How it is used

Geometry Influence Parameter (GIP) TipsGeometry Influence Parameter (GIP) Tips

Use default automatic setting unless an issue arises Good to use when optimizing water lines

Ideal should be used if going on to warpage Parameter can be used but not typically recommended

for warpage Automatic ~ GIP 10, so for large models you can set the

parameter lower• Reduces memory requirements but may affect accuracy of

results Set to a high number (20-30) if Ideal gives problems

Cooling Memory ErrorsCooling Memory Errors

ERROR 702270 Disk Space Free up more disk space for both job manger temp and

project directories Change GIP, especially if running Ideal If using a large model, change GIP to 6-10 Upgrade to higher amount of disk space

ERROR 700080 Memory (RAM + SWAP) Increase swap size

• Swapping to hard drive increases analysis time significantly• Watch CPU usage when swapping, normally under 10%

Upgrade to higher amount of RAM Try to lower element count

Remesh Convert Fusion > Midplane model

Fusion Thickness Change Issue Fusion Thickness Change Issue

MPI allow you to manually change element thickness properties Does not move mesh OK for Flow

Issue for cooling as solver (Boundary Element Method) relies partially on mesh location

Heat flux calculations do use thickness property Typically gives accurate results

This issue affects warp results Most accurate results obtained by making changes in

CAD and re-importing Fusion mesh

When to Run CoolingWhen to Run Cooling

Model part & mold Fill

Optimize filling of the part Balance/size feed system Possible packing

Cooling Minimize temp differences DON’T run filling as input to cool

Flow Optimize packing if necessary, Use cooling as input to Flow,

cooling may have strong influence on packing

Warp Determine type (midplane

only) Determine magnitude Determine cause Reduce warpage

ExerciseExercise

Run a cooling analysis on the dustpan Set inlets locations with

• Reynolds number 10,000• Water temperature 25º C

Run analysis with the following inputs• Mold surface temp: 40º C• Melt temp: 225º C• Mold-open: 5 sec• Inj + Pack + Cooling: Specified 15 sec• Geometry influence: Ideal

Run a second cooling analysis with Automatic IPC Compare the results from the two analyses

Results SummaryResults Summary

Automatic AnalysisSummary of Cavity Temperature Results =====================================Cavity temperature - maximum = 54.6 CCavity temperature - minimum = 29.4 CCavity temperature - average = 39.8 CAverage mold exterior temperature = 26.9 CCycle time = 66.0 s

Specified AnalysisSummary of Cavity Temperature Results =====================================Cavity temperature - maximum = 91.2 CCavity temperature - minimum = 35.6 CCavity temperature - average = 59.0 CAverage mold exterior temperature = 29.2 CCycle time = 20.0 s

Target Mold Temperature 40º C

Specified analysisCycle time 20 sec.

Avg. cavity temp. 59.0ºC

Automatic analysisCycle time 66.0 sec.

Avg. cavity temp. 39.8ºCTarget mold temp. 40ºC

Top TemperaturesTop Temperatures

Max Temp 54.6 ºC

Maximum TemperatureMaximum Temperature

Max Temp 54.6 ºC

Manual analysisCycle time 20 sec.

Avg. cavity temp. 59.0ºCEjection temperature 107ºC

Automatic analysisCycle time 66.0 sec.

Avg. cavity temp. 39.8ºCTarget mold temp. 40ºC

Average TemperatureAverage Temperature

Manual analysisCycle time 20 sec.

Automatic analysisCycle time 66.0 sec.

Target mold temp. 40ºC

Max. Value 46.0º

Time to FreezeTime to Freeze

Manual analysisCycle time 20 sec.

Automatic analysisCycle time 65.6 sec.

Max. Value 15.7 sec

Coolant TemperatureCoolant Temperature

Manual analysisCycle time 20 sec.

Automatic analysisCycle time 65.6 sec.

Max. Value 26.0º

QUESTIONS?QUESTIONS?