Bulk temperature is the velocity-weighted average melt temperature in the thickness direction at current time step.
The equation for calculating the bulk temperature is shown below:
Assuming the gap-wise direction is
, where t is the thickness of the cavity, v is the velocity of the melt, and T is the temperature of the melt.
In this result, the temperature contribution from frozen layer is neglected. The effect of heat convection and viscous heating can be observed from this data. Therefore, it can clearly demonstrate how heat convection affects the temperature distribution of hesitation and viscous heating area.
In general, bulk temperature distribution can reflect the trend of flow path and therefore the actual path of pressure transmission.