Pressure Drop in Non Circular Ducts
Posted on Tuesday, January 20, 2015 at 12:58 AM

 

Where to Find a Spreadsheet for Pressure Drop in Non Circular Ducts

To obtain a spreadsheet for  pressure drop in non circular ductsclick here to visit our spreadsheet store.  Intended for use in calculating flow rate or frictional head loss and frictional pressure drop, you can buy a convenient spreadsheet for  pressure drop in non circular ducts calculations for a very reasonable price.  This spreadsheet makes calculations with the Hagen Poiseuille equation for laminar flow and with the Moody friction factor and the Darcy Weisbach equation for turbulent flow for flow through an annulus and for flow through a rectangular duct.  Turbulent flow calculations can be made for a general non-circular duct with known cross-sectional area and wetted perimeter.  It is available in either U.S. or S.I. units.  Read on for information about a spreadsheet for pressure drop in a non circular duct calculations.

Turbulent Flow Pressure Drop in Non Circular Ducts

The Moody friction factor is used in the Darcy Weisbach equation for turbulent flow pressure drop through non circular ducts.  The Darcy Weisbach equation is:

Pressure Drop in Non Circular Ducts Equation

Where the hydraulic diameter is used for D in the Darcy Weisbach equation for flow through non circular ducts.  For further discussion of the Moody friction factor and its use in the Darcy Weisbach equation for pipe flow calculations, see the post, "Pipe Flow-Friction Factor Calculations with Excel Spreadsheets."

Laminar Flow Pressure Drop in Non Circular Ducts

For laminar flow in an annulus or laminar flow in a rectangular duct, the Hagen Poiseuille equation should be used.  For flow through an annulus, it is:

Pressure Drop in Non Circular Ducts Laminar Equations
Hagen Poiseiulle equations for laminar flow through an annulus

 

 Example Spreadsheet for Pressure Drop in Non Circular Ducts

A spreadsheet for flow through non circular ducts calculations is partially shown in the image below.  This Excel spreadsheet can be used to calculate the frictional pressure drop and head loss or flow rate for flow through an annulus (laminar or turbulent flow), flow through a rectangular duct (laminar or turbulent flow) or flow through a general non circular duct (turbulent flow only).  This Excel spreadsheet, as well as others for pipe flow calculations, is available in either U.S. or S.I. units for a very reasonable price in our spreadsheet store.

Flow Through Non Circular Ducts - Annulus

Reference:

Bengtson, Harlan,  "Spreadsheet for Flow Through Non Circular Ducts",  An online Blog article.