INTERNAL ROOM PRESSURE REGULATON WITH MOTORIZED DAMPER
INTERNAL ROOM PRESSURE REGULATON WITH MOTORIZED DAMPER
(OP)
Hi friends!
I have been asking me about what practical is controlling internal positive room pressure using arrangaement composed by Internal Pressure Sensor (as Magnahelic) + modulating motorized damper.
How quick is the control response? Is a realiable design? Wath level of precise control is achieved?
Thanks,
schola
I have been asking me about what practical is controlling internal positive room pressure using arrangaement composed by Internal Pressure Sensor (as Magnahelic) + modulating motorized damper.
How quick is the control response? Is a realiable design? Wath level of precise control is achieved?
Thanks,
schola





RE: INTERNAL ROOM PRESSURE REGULATON WITH MOTORIZED DAMPER
The problem is that pressure and flow are not linear. The pressure varies by the square of the cross-sectional area. So, a simple sensor and modulating actuator will constantly overshoot/undershoot.
You can measure this yourself. Typically, you will find that with a simple butterfly damper, there is no reduction in flow (pressure) until the last ~25% of movement. Multi-bladed, opposed blade, and airfoil-blade dampers will minimize this somewhat, but cannot remove the essential squared relationship.
Venturi valves, such as those made by Phoenix, are inherently linear by virtue of their geometric design.
RE: INTERNAL ROOM PRESSURE REGULATON WITH MOTORIZED DAMPER
If you balance the system manually first and also if you have variable volume systems, this may not be a difficult task.
RE: INTERNAL ROOM PRESSURE REGULATON WITH MOTORIZED DAMPER
I think the criticality of your application dictates what solution you need to apply.For eg,if it is a biocontanined lab,the investment on venturi valve is well worth it.On the other extreme,if it is a control room, a manual damper can do the job.