Pressure Drop Calculation

Transcription

1 Troubleshoot the following problem by using the information provided. The first 20 service technicians to fax the correct answer back to us will win $50. * Fax answers to: Jeff (800) Troubleshooting Contest Pressure Drop Calculation Please fill out the attached worksheet complete with pump curve plotted. Unit is a NDV064A111CTL with five vertical bores totalling 1500 feet of 0.75 pipe. Unit: NDV064A111CTL Antifreeze: Methanol (20%) Hose kit: Standard CK4L, 10 feet of Rubber hose. Inside Piping: feet total. Outside Piping: feet total. Circuit Piping: 0.75 Total Fittings: 6 Your Information: Dealer: Technician: Phone: Address: * This contest is part of the WaterFurnace E-News sent on Friday. Answers to this problem must be received by 5pm the following Tuesday to qualify. WFTC023

2 Residential Pressure Drop Calculation Worksheet Job/Client Name GSC Technician Loop Description Total Trench/Bore Number of Circuits Antifreeze Minimum Loop Temperature a. WF Unit gpm ft. of hd. x temp. corr. factor = ft. of hd. 1 b. Hose gpm ft. x ft. of hd./100 ft. = ft. of hd. c. Inside gpm ft. x ft. of hd./100 ft. = ft. of hd. (Flow Center to Unit) Pipe Size TOTAL Unit #1 a. WF Unit gpm ft. of hd. x temp. corr. factor = ft. of hd. b. Hose gpm ft. x ft. of hd./100 ft. = ft. of hd. 2 c. Inside gpm ft. x ft. of hd./100 ft. = ft. of hd. (Flow Center to Unit) Pipe Size TOTAL Unit #2 ft. of hd. Unit TOTAL (Largest of Total Unit #1 and Unit #2) ft. of hd Inside Supply Return Piping(to gpm ft. x ft. of hd./100 ft. = ft. of hd. Pipe Size Outside Supply & Return gpm ft. x ft. of hd./100 ft. = ft. of hd. Pipe Size Circuit gpm ft. x ft. of hd./100 ft. = ft. of hd. Pipe Size 6 Fittings (Add 2 ft. of hd. for every 10 fittings) ft. of hd. TOTAL SYSTEM PRESSURE DROP Total gpm= Total pressure drop= ft. of hd. The purpose of the following formulas is to generate 3 points on the system performance curve. Point 1 Total gpm = 3 gpm per ton = Total pd = pd of the system = Point 2 Total gpm 2 =.667 x gpm = Total pd 2 =.5 x pd = Point 3 Total gpm 3 = 1.33 x gpm = Total pd 3 = 2 x pd = Grundfos Pump Curve - UP26-99 HEAD (FEET) UP26-99 SINGLE UP26-99 DOUBLE Point 1 is generated from the design flow need and the pressure drop (pd) associated with this particular piping system. Points 2 and 3 are generated from point FLOW (GPM) NOTE: If using pumps other than shown, refer to the manufacturer s performance data. for those pumps

3 Unit Pressure Drop Tables Residential Unit Pressure Drop Closed Loop (minimum) Closed Loop (optimum) Series Model & Size Flow Rate Pressure Drop* Flow Rate Pressure Drop* GPM PSI Ft. Head GPM PSI Ft. Head NS NS Envision NS Single Speed NS NS NS NS ND026 Low ND026 High ND038 Low Envision ND038 High Dual Capacity ND049 Low ND049 High ND064 Low ND064 High ND072 Low ND072 High E E E & EZ E Single Speed E E E E E036 Low E036 High E048 Low E & EZ E048 High Dual Capacity E060 Low E060 High E072 Low E072 High ES ES Single Speed ES ES036 Low ES036 High ES048 Low ES ES048 High Dual Capacity ES060 Low ES060 High ES072 Low ES072 High RT Synergy3 RT RT * Pressure Drops shown at 50ºF EWT. For Pressure Drops at other EWTs, use table below. Ent. Water Temp. Correction ºF ºC Factor

4 Pipe Pressure Drop Tables Pressure Drop for Rubber Hose Per 100 ft, of hose, in feet of head BRINE 1 32 F BRINE 4 20% 30 F Viscosity lbm/ft sec Darcy-Weisbach Method Viscosity lbm/ft sec Darcy-Weisbach Method Density lb/ft3 Density lb/ft3 FLOW 1 IPS RUBBER HOSE 1 1/2 IPS RUBBER HOSE FLOW 1 IPS RUBBER HOSE 1 1/2 IPS RUBBER HOSE RATE PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re RATE PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re Rev. 1/06 Rev. 1/06 BRINE 8 25% 30 F BRINE 5 30% PROPYLENE 30 F Viscosity lbm/ft sec Darcy-Weisbach Method Viscosity lbm/ft sec Darcy-Weisbach Method Density lb/ft3 Density lb/ft3 FLOW 1 IPS RUBBER HOSE 1 1/2 IPS RUBBER HOSE FLOW 1 IPS RUBBER HOSE 1 1/2 IPS RUBBER HOSE RATE PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re RATE PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re Rev. 1/06 Rev. 1/06

5 Pipe Pressure Drop Tables (cont.) Pressure Drop, Polyethylene Pipe, SDR 11 Per 100 ft. of pipe, in feet of head BRINE 1 32 F Viscosity lbm/ft sec Density lb/ft3 Darcy-Weisbach Method FLOW RATE 3/4 IPS SDR 11 1 IPS SDR /4 IPS SDR /2 IPS SDR 11 2 IPS SDR 11 PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re Rev. 1/06 BRINE 2 50 F Viscosity lbm/ft sec Density lb/ft3 Darcy-Weisbach Method FLOW RATE 3/4 IPS SDR 11 1 IPS SDR /4 IPS SDR /2 IPS SDR 11 2 IPS SDR 11 PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re Rev. 1/06

6 Pipe Pressure Drop Tables (cont.) Pressure Drop, Polyethylene Pipe, SDR11 Per 100 ft. of pipe, in feet of head BRINE 8 25% 30 F Viscosity lbm/ft sec Density lb/ft3 Darcy-Weisbach Method FLOW 3/4 IPS SDR 11 1 IPS SDR /4 IPS SDR /2 IPS SDR 11 2 IPS SDR 11 RATE PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re Rev. 1/6/06 BRINE 4 20% 30 F Viscosity lbm/ft sec Density lb/ft3 Darcy-Weisbach Method FLOW RATE 3/4 IPS SDR 11 1 IPS SDR /4 IPS SDR /2 IPS SDR 11 2 IPS SDR 11 PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re Rev. 1/6/06

7 Pipe Pressure Drop Tables (cont.) Pressure Drop, Polyethylene Pipe, SDR 11 Per 100 ft. of pipe, in feet of head BRINE 5 30% PROPYLENE 30 F Viscosity lbm/ft sec Density lb/ft3 Darcy-Weisbach Method FLOW 3/4 IPS SDR 11 1 IPS SDR /4 IPS SDR /2 IPS SDR 11 2 IPS SDR 11 RATE PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re PD (ft) Vel ft/s Re Rev. 1/06