Air Jet cone angle

[Francis]

I need to calculate the cone angle of the air jet coming out of a hole on the circumference of a pressurized air pipe. Please tell me a source from where I can get the relevant formula or see a sample calculation.
Thanks.

 

[butelja]

Perry's Chemical Engineers Handbook has a section on "Turbulent Free Jets" in chapter 5. The jet divergence angle, alpha, is given as 20° for distances less than 100 diameters from the orifice. The correlation given is valid for distances varying from 7 to 100 jet diameters, with initial jet velocities from 2.5 to 50 m/s.