Extruded polymer volume vs extrusion hole diameter and length

[AligatorAmy]

Hi,

I have the polymer (PP) extrusion die. The die includes 0.25mm diameter holes. The length of each extrusion hole is 2.5mm (L/D ration is 10).

I need to decrease extrusion hole diameter from 0.25mm to 0.20mm.

I would like to calculate how much less polymer (volume) will be pushed through single 0.20mm diameter extrusion hole when compared to 0.25mm hole, for specific length of extrusion hole.

I am looking for formula/literature. I have searched the literature. However, most of it refers to calculating the extruder speed, etc. I do not want to change extruder speed (polymer pressure), polymer temperature, polymer itself.

Please also refer to attached draft.

I would be very obliged for any help.

Thanks.
Regards