AXIAL FAN FLOW

[Jinder]

I am trying to set up an axial fan rig. I have calculated the max. mass flow through it, and now need to find out what size ORIFICE PLATE should be used. I have a copy of BS 1042, but this is since 1943, far too old with imperial units not metric. This has examples of how to calculate the orifice plate size but isnt too helpful for this day and age. I have looked at the new updated British Standard on-line but it is only in parts and still doesn't give sufficient detail.

I need an equation that is used to find this out. How can I find this out? which British Standard covers this flow measurement?

 

[ChasBean1]

Jinder, how did you &quot;calculate&quot; the max mass flow rate through the fan? This would be more accurately based on the fan operating curve for it's given RPM at zero pressure drop across it. Also, what is the purpose of the orifice plate - are you trying to achieve a critical flow condition (e.g., P1 << .5 P2)?

 

[Jinder]

I worked out the mass flow rate by:
m= rho*V*A
Rho = 1.164030723
Area = 0.035210185

Delta P = 0.5*Rho*V^2
V = (Delta P/0.5*Rho)^0.5
Rad @ mid height = 0.09625

At the moment all it is, is a fan, it need to be used as a rig eventually. I need to extend the flow, and fit in an orifice plate to calibrate the fans characteristics

At a blade speed of 7.559ms the mass flow rate was 0.215kg/s
At a blade speed of 16.127 ms it was 0.476kg/s