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' - Unlevel Pressure Distribution System Design - 10/25/04 <br /> 1. Lay out system in order of highest to lowest elevation <br /> Line 1 Elevation 111.2 ft Length 92 ft <br /> Line 2 Elevation 110.2 ft Length 92 ft <br /> Line 3 Elevation ft Length ft <br /> �- <br /> Linei 4 Elevation ft Length ft <br /> Line� 5 Elevation ft Length � ft <br /> 2. Change in Elevation over the Trenches <br /> Highest elevation-lowest elevation: 111.2 - 110.2 = 1.0 feet <br /> 3. Total Head=head at orifices(2ft)+change in elevation(2) 2 ft + 1.0 ft = 3.0 feet <br /> (if greater than 5 feet modify design) <br /> 4. Calculate pressure head for each system <br /> 1. Highest Trench Elevafion the Head=2 feet <br /> 2. Po+ (E1 -Ex)=DEx <br /> Line 1 Elevation 111.2 2+ [E1 -E1]=2+ [ 111.2 - 111.2 ] = 2.0 feet <br /> Line 2 Elevation 110.2 2+[E1 -E2]=2+ [ 111.2 - 110.2 ] = 3.0 feet <br /> Line 3 Elevation 0.0 2+ [E1 -E3]=2+ [ 111.2 - 0.0 ]= 0.0 feet <br /> Line 4 Elevation 0.0 2+[E1 -E4]=2 +[ 111.2 - 0.0 ]= 0.0 feet <br /> Line 5 Elevation 0.0 2+[E1 -E5j=2 + [ 111.2 - 0.0 ] = 0.0 feet <br /> 5. Determine flow rate per hole(See figure E-6) <br /> Line 1 Pres 2.0 Perf Diameter 7/32 = 0.80 gpm <br /> Line 2 Pres 3.0 Perf Diameter 7/32 = 0.98 gpm <br /> Line 3 Pres 0.0 Perf Diameter = gpm <br /> Line 4 Pres 0.0 Pert Diameter = gpm <br /> Line 5 Pres 0.0 Perf Diameter = gpm <br /> 6. Calculate flow for Line 1 <br /> Number of perForations= len th of pipe-2)/spacing]+1 <br /> [( 92 ft-2ft) / 3 ft]+1 = 31 pertorations(Check figure E-4 to make sure it is ok) <br /> Flow= number of perforations x flow rate <br /> 31 perf x 0.80 gpm = 24.8 gpm <br /> 7. Calculate the gallons per foot for Line 1 <br /> Gallons/length= 24.8 gpm / 92 ft= 0.27 gpm/ft <br /> E�Perforation Discha e in GPM E-d Maximum Number of 1/4 inch pertorations <br /> Pressure r lateral to uarantee<10°k discha e variation <br /> Head Perforation Diameter in inches Perforation <br /> feet 1/8 3/16 7/32 1/4 Spacing <br /> 1 0.18 0.42 0.56 0.74 feet 1 inch 1.25 incl 1.5 inch 2.0 inch <br /> 1.5 0.22 0.51 0.68 0.90 2.5 8 14 18 28 <br /> 2 0.26 0.59 0.80 1.04 3.0 8 13 17 26 <br /> 2.5 0.29 0.65 0.88 1.17 3.3 7 12 16 25 <br /> 3 0.32 0.72 0.98 1.28 4.0 7 11 15 23 <br /> 4 0.37 0.83 1.13 1.47 5.0 6 10 14 22 <br /> 5 0.41 0.94 1.26 1.65 Page 1 of 2 <br />