Chimneys vapor flow, pressure drop

The pressure drop of the vapor flowing through the chimneys. The liquid on the tray has to develop enough liquid head to flow against the higher pressure below the tray. 

The pressure drop of the vapor flowing through the chimneys is... 

The chevron collector features a high open area for vapor flow, and is therefore a low-pressure-drop device. Pressure drop is usually less than 0.1 in of water (74). This type of collector is most suitable for vacuum applications. This collector also acts as a vapor distributor accordingly, the distance required between the top of this collector and the support plate above is less than 12 in (74). The short vertical distance requirement of this device compared to the chimney tray often makes it less expensive than the chimney tray. 

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