Static Pressure Calculator

L = CENTER DISTANCE INCHES 34DUCT DIA 18

VELOCITY 1500Q = Air Flow Rate, CFM 2650.725 1. Enter number for L in inches D = DUCT DIA IN FEET 1.5 2. Enter Duct Diameter

A = AREA, Feet Squared 1.76715 3. Enter Velocity V = AIR VELOCITY, Feet Per Minute 1500 4. Enter C - dynamic loss coefficient

VP = VELOCITY PRESSURE 0.1402741 5. Then get SP for each piece of ductL = CENTER LINE DISTANCE, Feet 2.83333333 6. Do this for each duct piece to get Total SP for systemC = DYNAMIC LOSS COEFFICIENT 1.25

DUCT STATIC PRESURE = FRICTION LOSS + DYNAMIC LOSS

SPF = FRICTION LOSS 0.00516676SPD = DYNAMIC LOSS 0.17534262

SP = STATIC PRESSURE 0.18051

PART L Center Distance in InchesFactory Installed Riser 4

Field Installed Riser 4Straight Duct Depends on Length

Adjustable Duct Depends on Length minus Minimum OverlapAdaptor (all sizes) 13

90 Elbow (8" diameter) 1590 Elbow (10" diameter) 1690 Elbow (12" diameter) 17.590 Elbow (14" diameter) 18.790 Elbow (16" diameter) 2190 Elbow (18" diameter) 2290 Elbow (20" diameter) 23.590 Elbow (24" diameter) 26.545 Elbow (8" diameter) 8.8

45 Elbow (10" diameter) 9.545 Elbow (12" diameter) 10.245 Elbow (14" diameter) 10.945 Elbow (16" diameter) 11.645 Elbow (18" diameter) 12.345 Elbow (20" diameter) 1345 Elbow (24" diameter) 14.4Duct Tee (8" diameter) 15

Duct Tee (10" diameter) 17Duct Tee (12" diameter) 19Duct Tee (14" diameter) 21Duct Tee (16" diameter) 23Duct Tee (18" diameter) 25Duct Tee (20" diameter) 27Duct Tee (24" diameter) 31

Y Tee (12" diameter) 28Y Tee (14" diameter) 30Y Tee (18" diameter) 33.5Y Tee (20" diameter) 35.5Y Tee (24" diameter) 54

Off Set Collar 4 when matched with horizontal run

8" Duct DiameterDuct Component Dynamic Loss Coefficient

RISER/FRISER 0.017STRAIGHT/ADJ See Design Guide

ADAPTOR (8 TO 12) 0.79790 ELBOW 0.40045 ELBOW 0.150DUCT TEE 1.250

10" Duct DiameterDuct Component Dynamic Loss Coefficient

RISER/FRISER 0.013STRAIGHT/ADJ See Design Guide

ADAPTOR (10 TO 14) 0.47090 ELBOW 0.42045 ELBOW 0.150DUCT TEE 1.250

12" Duct DiameterDuct Component Dynamic Loss Coefficient

RISER/FRISER 0.011STRAIGHT/ADJ See Design Guide

ADAPTOR (12 TO 18) 0.79790 ELBOW 0.44045 ELBOW 0.150DUCT TEE 1.250

Y TEE 0.600

14" Duct DiameterDuct Component Dynamic Loss Coefficient

RISER/FRISER 0.010STRAIGHT/ADJ See Design Guide

ADAPTOR (14 TO 20) 0.52290 ELBOW 0.46045 ELBOW 0.150DUCT TEE 1.250

Y TEE 0.600

16" Duct DiameterDuct Component Dynamic Loss Coefficient

RISER/FRISER 0.008STRAIGHT/ADJ See Design Guide

ADAPTOR (16 TO 24) 0.79790 ELBOW 0.480

45 ELBOW 0.150DUCT TEE 1.250

18" Duct DiameterDuct Component Dynamic Loss Coefficient

RISER/FRISER 0.006STRAIGHT/ADJ See Design Guide

90 ELBOW 0.50045 ELBOW 0.150DUCT TEE 1.250

Y TEE 0.600

20" Duct DiameterDuct Component Dynamic Loss Coefficient

RISER/FRISER 0.005STRAIGHT/ADJ See Design Guide

90 ELBOW 0.52045 ELBOW 0.150DUCT TEE 1.250

Y TEE 0.600

24" Duct DiameterDuct Component Dynamic Loss Coefficient

RISER/FRISER 0.004STRAIGHT/ADJ See Design Guide

90 ELBOW 0.54045 ELBOW 0.150DUCT TEE 1.250

Y TEE 0.600

Straight and Adjustable Dynamic Loss Coefficient Table

Straight and Adjustable Dynamic Loss Coefficient Table

Duct Velocity (V) = CFM/Area (in ft sq) = FPM

Round Area8" = 50.24 in sq or 0.348 ft sq10" = 78.5 in sq or 0.545 ft sq

12" = 113.04 in sq or 0.79 ft sq14" = 153.86 in sq or 1.07 ft sq16" = 200.96 in sq or 1.40 ft sq18" = 254.34 in sq or 1.77 ft sq20" = 314.00 in sq or 2.18 ft sq24" = 452.16 in sq or 3.14 ft sq

Square Area12" = 144 in sq or 1.00 ft sq14" = 196 in sq or 1.36 ft sq16" = 256 in sq or 1.78 ft sq18" = 324 in sq or 2.25 ft sq20" = 400 in sq or 2.78 ft sq22" = 484 sq in or 3.36 ft sq24" = 576 sq in or 2.00 ft sq