Sheet1The Spitzglass EquationPressure unitsTemperature UnitsLength unitsViscosityVolume flowratehttp://excelcalculations.blogspot.com

ParameterspsiaRinPa sft^3/dayInlet pressure (absolute)1PaKmcPm^3/sOutlet pressure (absolute)0.0253milesPressure, std condition (absolute)14.7UnitValue in ImperialTemperature std condition (absolute)520Inlet pressure11Mean temperature of line (absolute)520Outlet pressure10.0253Inside diameter6.065Pressure, std condition114.7Pipe length2160Temperature std condition1520Gas relative density (air=1)0.6Mean temperature of line1520Mean gas compressibility1Inside diameter16.065Pipeline efficiency1Pipe length10.0340909091Elevation of exit above entrance0Gas relative density (air=1)Mean gas compressibilityFlowrates (std conditions)Pipeline efficiencySpitzglass Low Pressure2794842.15876289Pipe effective roughnessSpitzglass High Pressure537841.929502596Mean gas viscosity2ERROR:#REF!s10Le0.0340909091Spitzglass low pressure12794842.15876289Spitzglass high pressure1537841.929502596

Sheet2The Spitzglass Equation for Sizing Gas Pipelines

Originally published in 1912, the Spitzglass Equation is used for sizing fuel gas pipes (although now it is superseded by better correlations). Two versions of the equation exist; one for low pressures (below 1 psi or 6.9 kPa) and another for medium pressures (above 1 psi or 6.9 kPa). However, both equations are typically used at near-atmospheric conditions, with pipe diameters below 10 inches (otherwise the friction factor is not accurately modeled).

This Excel spreadsheet solves both versions of the Spitzglass equations, with full units support.

The equations implemented are as follows

Spitzglass Low Pressure (1 psi)

The notation is given here. These equations differ slightly to those versions typically presented in the literature because they include the effect of gas compressibility, and vertical pipe travel (i.e. potential energy).

I've also implemented other equations for sizing gas pipelines, including the Weymouth Equation, Panhandle Equation and the IGT Distribution Equation.

Sheet3