Capacity of blower system.

[baks]

Dear All

On one of the systems in our plant we have 2 x 2,4 m³/hr ring blowers installed in parrallel and further upstream a 5m³/hr ring blower installed in series with the two parrallel ones how does one determine the maximum discharge capacity of such a system

THANKS IN ANTICIPATION

 

[TD2K]

Time to break out your calculator or better, spreadsheet. What you need to do is develop the system curve. Basically,what I understand you have is:

A source,
A possible section of inlet piping,
1 blower (you used the term upstream, I'm assuming this is the first blower in the system, 5 m3/hr),
more piping
2, 50% blowers (2.4 m3/hr each)
more piping
final delivery point.

Basically, it's a pressure drop/flow calculation through the system. You'll need to adjust the flow rate through the system until the pressure drops through the piping and change in delivery conditions equal the pressure rises added by the blowers. It's a trial and error calculation thus the best way is to set it up on Excel and curve fit the blower curves so you can easily adjust conditions.

Let's say you were compressing from 0 psig to 20 psig. Adjust the flow rate through the system until the line losses + 20 psi (change in source/delivery pressure) equals the sum of the pressure rise from the blowers that are operating. Change the source or delivery pressure, you get a new flow rate. Change the number of blowers online, you get a new flow rate. Change the fluid properties, you get a new flow rate.