How to Calculate Orifice Size for Fluid Flow Dispensing?

[Fred Evans]

hello all,

i need to calculate the size of an orifice that will pass a certain volume of a viscous fluid

per time of say 10 seconds

pressure and viscosity are the variable values.

the application is in the design of a valve for dispensing accurate amounts of
a liquid of a given viscosity. (the liquid is polyurethane prepolymer which is a sticky
fluid of which the viscosity is always known but varies from batch to batch)

the viscosity changes with temperature

Can anyone please suggest a formula ?

Best regards

fred evans

( this is my first post-- and I see i can attach 5 tags-- what is a tag?

 

[anorlunda]

There are many flow calculators online that you can use. Here is one:

https://checalc.com/calc/smallLiqOrifice.html