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Dia AirProcedure for Air in DuctworkGlobal InputsDesign Static Press Loss:0.08"wg / 100'KINEMATIC VISCOSITY:0.0001623FT^2/SECAir Spec Vol:13.1061598952Ft^3/# DAfor comparisonDuplicateUDFCell M83AirDiaLong-Hand version of the UDF AirDiaCFM =6Dia =2.15712.15711st table (or Do Loop Until in macro) get within 50% of the diameterLoop until the "Diff" turns positivedia DCFMAbsRoughVelRelRoughRey#fCalcDarcy-WDesignDiffDup Col A2.0060.00032750.00180047080.039960.110.08-0.032.003.0060.00031220.00120031390.044010.020.080.063.004.5060.0003540.00080020930.049360.000.080.084.506.7560.0003240.00053313950.045880.000.080.086.7510.1360.0003110.0003569300.068810.000.080.0810.1315.1960.000350.0002376200.103220.000.080.0815.1922.7860.000320.0001584130.154830.000.080.0822.7834.1760.000310.0001052760.232250.000.080.0834.1751.2660.000300.0000701840.348370.000.080.0851.2676.8960.000300.0000471220.522560.000.080.0876.89115.3360.000300.000031820.783830.000.080.08115.33Vlookup2.002nd table (or Do Loop Until in macro) gets within 5% of the diameterDesignLoop until the "Diff" turns positivedia DCFMAbsRoughVelRelRoughRey#fCalcDarcy-WDesignDiffDup Col A2.0060.00032750.00180047080.039960.110.08-0.03492.002.1060.00032490.00171444840.040380.090.08-0.0112.1002.2160.00032260.00163342710.040820.070.080.0082.2052.3260.00032050.00155540670.041270.060.080.02292.322.4360.00031860.00148138740.041750.050.080.03482.432.5560.00031690.00141036890.042240.040.080.04412.552.6860.00031530.00134335130.042750.030.080.05162.682.8160.00031390.00127933460.043280.020.080.05742.812.9560.00031260.00121831870.043830.020.080.06212.953.1060.00031140.00116030350.044400.010.080.06583.10Vlookup2.10Perform slope and projection calc; use another Do Loop Until in macroLoop Until "LoDiff is negative and "HiDiff" is positiveLo DiaLo CFMAbsoluteLo VelLoRelRoughLo Rey#Lo fCalcLo D-WLoDesignLo DiffHi DiaHi CFMRoughnessHi VelHiRelRoughHi Rey#Hi fCalcHi D-WHiDesignHi DiffSlopeProj Dia2.0979060.00032500.00171644890.040370.09140.08-0.01140.207132.15282.1021060.00032490.00171344800.040390.09050.08-0.01052.1506860.00032380.00167443780.040590.08110.08-0.00110.179272.15712.1549960.00032370.00167143700.040610.08040.08-0.00042.1549060.00032370.00167143700.040610.08040.08-0.00040.177252.15712.1592160.00032360.00166743610.040630.07960.080.0004Verification of ProjDia, ProjDia plus .0001 and ProjDia minus .0001Verification Usingdia DCFMAbsRoughVelRelRoughRey#fCalcDarcy-WUDF AirPD2.157160.00032360.00166943650.040620.080000.08000Using the calculated diameter2.157060.00032360.00166943660.040620.080020.08002Using the calculated diameter minus .0001 inches2.157260.00032360.00166943650.040620.079980.07998Using the calculated diameter plus .0001 inches

Dia Air

DiameterDiff = Design Loss - Actual LossDiff vs Diameter in 1.5 x Steps

Cap Air

DiameterDiff = Design Loss - Actual LossDiff vs Diameter in 1.05 x Steps

ExamplesProcedure for Air in DuctworkGlobal InputsDesign Static Press Loss:0.08"wg / 100'KINEMATIC VISCOSITY:0.0001623FT^2/SECAir Spec Vol:13.1061598952Ft^3/# DA622.282Range from 1 CFM to 1,000,000 CFMUDFLong-Hand version of the UDF AirCapDiameter =12inchesCFM =622.28622.281st table (or Do Loop Until in macro) get within 50% of the diameterLoop until the "Diff" turns positiveUDF AirPDCFMDiaAbsRoughVelRelRoughRey#fCalcDarcy-WDesignDiffDup Col A1120.00031.2730.0003001310.489340.00000.0800-0.081.000.000010120.000312.7320.00030013080.048930.00010.0800-0.0810.000.0001100120.0003127.3240.000300130790.029320.00300.0800-0.08100.000.00301000120.00031273.2410.0003001307870.018720.19220.08000.111000.000.192210000120.000312732.4060.00030013078730.0155015.92080.080015.8410000.0015.9208100000120.0003127324.0620.000300130787280.015001540.05220.08001539.97100000.001540.05221000000120.00031273240.6200.0003001307872770.01494153442.95310.0800153442.871000000.00153442.9531Vlookup100.002nd table (or Do Loop Until in macro) gets within 5% of the diameterDesignLoop until the "Diff" turns positiveCFMDiaAbsRoughVelRelRoughRey#fCalcDarcy-WDesignDiffDup Col A100.00120.0003127.3240.000300130790.029320.00300.0800-0.08100.00150.00120.0003190.9860.000300196180.026650.00620.0800-0.07150.00225.00120.0003286.4790.000300294270.024380.01270.0800-0.07225.00337.50120.0003429.7190.000300441410.022450.02630.0800-0.05337.50506.25120.0003644.5780.000300662110.020840.05480.0800-0.03506.25759.38120.0003966.8670.000300993170.019490.11540.08000.04759.381139.06120.00031450.3010.0003001489750.018390.24490.08000.161139.06Vlookup506.252nd table (or Do Loop Until in macro) gets within 5% of the diameterDesignLoop until the "Diff" turns positiveCFMDiaAbsRoughVelRelRoughRey#fCalcDarcy-WDesignDiffDup Col A506.25120.0003644.5780.000300662110.020840.05480.0800-0.0252506.25531.56120.0003676.8070.000300695220.020660.05990.0800-0.0201531.56558.14120.0003710.6470.000300729980.020490.06550.0800-0.0145558.14586.05120.0003746.1800.000300766480.020320.07170.0800-0.0083586.05615.35120.0003783.4890.000300804800.020160.07840.0800-0.0016615.35646.12120.0003822.6630.000300845040.020000.08570.08000.0057646.12678.42120.0003863.7960.000300887290.019840.09380.08000.0138678.42712.34120.0003906.9860.000300931660.019690.10260.08000.0226712.34747.96120.0003952.3350.000300978240.019540.11220.08000.0322747.96785.36120.0003999.9520.0003001027150.019390.12280.08000.0428785.36Vlookup615.35646Perform slope and projection calc; use another Do Loop Until in macroLoop Until "LoDiff is negative and "HiDiff" is positiveLo CFMLo CFMAbsoluteLo VelLoRelRoughLo Rey#Lo fCalcLo D-WLoDesignLo DiffHi CFMHi CFMRoughnessHi VelHiRelRoughHi Rey#Hi fCalcHi D-WHiDesignHi DiffSlopeProj CFM645.47120.0003821.8400.000300844190.020000.08560.08000.0056645.470.0002437373622.667085.4976804783646.76120.0003823.4860.000300845880.019990.08590.08000.0059646.76622.04120.0003792.0070.000300813550.020120.07990.0800-0.0001622.040.0002360768622.287079.7331600371623.29120.0003793.5920.000300815180.020110.08020.08000.0002623.29621.66120.0003791.5220.000300813050.020120.07990.0800-0.0001621.660.000235946622.287079.730191782622.90120.0003793.1060.000300814680.020120.08010.08000.0001622.90

Procedure for Air in Ductwork; Examples of AirDia, Wcalc and AirPDIn these examples, we will use Global Inputs (applicable to all calcs) for Design Static,Kinematic Viscosity and Specific Volume. They are "absolute references" in the UDF's.Global InputsDesign Static Press Loss:0.08"wg / 100'KINEMATIC VISCOSITY:0.0001623FT^2/SECAir Spec Vol:13.1061598952Ft^3/# DAFor each leg, we can input a flow (CFM) and Absolute Roughness in columns B and C respectively.The Duct Diameter is automatically calculated in in column DFor a Rectangular equivalent, enter the height in column F and the width is calculated in column GThe results are verified by calculating the actual pressure drop and the equivalent diameterUDFVerificationVerificationUDFINPUT AWcalcTest AreaUDFEquiv Diaduct legairflow QAbsoluteAirDiaheight awidth bto enter theAirPDusingcfmRoughnessinininUDF AirDia"wg / 100'Huebscher116000.000517.251417.860.0800017.25214000.000316.271415.840.0800016.27310000.00114.691412.900.0800014.69410000.000514.451412.500.0800014.45510000.000314.341412.300.0800014.34Likewise the Capacity can be calculated using the diameter calculated above and comparedto the flow from column B above for verification.UDFThis example sheet can be easily modified to be used as a simpleduct legDiameterAbsoluteAirCapduct analyzing tool.inches\Roughnessin117.25190.00051600216.27110.00031400314.68640.0011000414.45340.00051000514.33780.00031000