COOL, FLOW, PACK, and WARP modules

The injection molding simulation is performed with four analysis modules: COOL, FLOW, PACK, and WARP.


Performs heat transfer analysis with the objective of obtaining the distribution of temperature within the mold. During the injection molding cycle, computed temperatures vary by location, and also over time. The effects of the cavity filling and the mold's cooling system are included in the COOL simulation. Since temperature changes occur relatively slower compared to the speed at which the cavity is filled, an approximation is made in the software that allows the COOL simulation to be conducted first, separately from the FLOW simulation. Temperature results from COOL are stored in a database for use in subsequent FLOW and PACK simulations.

To further simplify the problem, you can optionally skip the COOL simulation, and simply enter temperature data as either a single uniform value for the entire cavity surface ( Fill Settings PropertyManager > Mold Temperature ), or by selecting various surfaces and specifying their temperature values ( Boundary Conditions > Mold Temperature PropertyManager ).

The COOL analysis module is available with the SOLIDWORKS Plastics Premium product.


Predicts how material fills the cavity. It accounts for heat transfer between the material and mold during filling, and predicts the changes to viscosity as the material begins to solidify. Results of the FLOW simulation include distributions of pressure and temperature within the cavity, and detection of potential short shots and weld lines.

You can control how material is injected into the cavity by specifying either filling time, an injection flow rate, or screw velocity profile. Selecting AUTO, the software applies the process parameters automatically (Fill Settings PropertyManager).


Evaluates the material freezing process in the cavity. During PACK, pressure is applied to the injection system to cause additional material to enter the cavity as the part shrinks and freezes. To control the switch over from FLOW to PACK, you can specify a time value, or a cavity fill percentage ( Fill Settings PropertyManager > Flow/Pack Switch Point in Filled Volume ).

You can run PACK with a constant or variable pressure, specified as an absolute value, or as a percentage of the injection pressure from the end of the FLOW simulation (Pack Settings PropertyManager > Profile).

PACK results predict the temperature time history at every point of the part, allowing you to evaluate hot spots, gate freeze, and cycle time. Distributions of pressure, stress, and shrinkage results are also available from PACK simulation.

From FLOW and PACK analysis, you can estimate the optimal process conditions, such as: filling time, injection pressure profile, pressure holding time, proper melt temperature and mold temperature. Furthermore, you can acquire information about the optimal mold design parameters such as: gate position, runner design, and cavity thickness.


Predicts the final shape and dimensions of the part, after it has been ejected and fully cooled. The WARP module uses residual stress data results from FLOW and PACK. Unlike the finite volume flow analysis used in FLOW and PACK, the WARP simulation is based on the finite element method, and the plastic part is considered a linear elastic body (small deformations are considered). Gates and runners may be excluded from WARP to focus only on the trimmed cavity part.

The WARP analysis module is available with the SOLIDWORKS Plastics Premium product.