Flow Rate Calculator

With this tool, it is possible to easily calculate the average flow rate of fluids by changing each of the three variables: length, pressure and bore diameter. The effects on the predicted flow rate are then given in three graphs, where in turn two of the variables are kept constant and the flow rate is plotted against a range of values of the third.

To begin calculating, enter the figures in the boxes below. If a value is not available for any one of the variables, then please leave the field blank and the program will select its own value. After scrutinising the results, it may be necessary to adjust a variable to provide an improved set of graph profiles to send to the enquirer.

Results

Please click on the tabs below to view the graph and data.

Quantity Fluid Flow vs Hose Length

Quantity Fluid Flow vs Pressure

Quantity Fluid Flow vs Bore Diameter

Quantity Fluid Flow vs Hose Length Data
Length20.00040.00060.00080.000100.000120.000140.000160.000180.000200.000
Qty fluid flow (ltrs/min)95.27368.45856.20248.80743.72739.96137.02634.65632.68931.023
Bore dia (mm)25252525252525252525
Pressure (bar)7777777777
Bore dia (ins)0.9840.9840.9840.9840.9840.9840.9840.9840.9840.984
Pressure (psi)102.900102.900102.900102.900102.900102.900102.900102.900102.900102.900
Length (ft)65.667131.333197.000262.667328.333394.000459.667525.333591.000656.667
Qty fluid flow (gals/min)20.96015.06112.36410.7389.6208.7918.1467.6247.1926.825
Coefficient C20.10520.10520.10520.10520.10520.10520.10520.10520.10520.105
Velocity V( ft/sec)10.6027.6186.2545.4314.8664.4474.1203.8563.6383.452
Bore dia (ft) D0.0820210.0820210.0820210.0820210.0820210.0820210.0820210.0820210.0820210.082021
EquivTtl head fluid h (ft)237.644237.644237.644237.644237.644237.644237.644237.644237.644237.644
Quantity Fluid Flow vs Pressure Data
Pressure1.4002.8004.2005.6007.0008.4009.80011.20012.60014.000
Qty fluid flow (ltrs/min)19.55527.65533.87139.11043.72747.90051.73855.31058.66661.839
Bore dia (mm)25252525252525252525
Length100100100100100100100100100100
Bore dia (ins)0.9840.9840.9840.9840.9840.9840.9840.9840.9840.984
Pressure (psi)20.58041.16061.74082.320102.900123.480144.060164.640185.220205.800
Length (ft)328.333328.333328.333328.333328.333328.333328.333328.333328.333328.333
Qty fluid flow (gals/min)4.3026.0847.4528.6049.62010.53811.38212.16812.90613.605
Coefficient C20.10520.10520.10520.10520.10520.10520.10520.10520.10520.105
Velocity V( ft/sec)2.1763.0773.7694.3524.8665.3305.7576.1556.5286.881
Bore dia (ft) D0.0820210.0820210.0820210.0820210.0820210.0820210.0820210.0820210.0820210.082021
EquivTtl head fluid h (ft)47.52995.058142.587190.115237.644285.173332.702380.231427.760475.289
Quantity Fluid Flow vs Bore Diameter Data
Bore Diameter5.00010.00015.00020.00025.00030.00035.00040.00045.00050.000
Qty fluid flow (ltrs/min)0.0912.2048.79221.98943.72775.790119.849177.478250.177339.374
Pressure (bar)7777777777
Length100100100100100100100100100100
Bore dia (ins)0.1970.3940.5910.7870.9841.1811.3781.5751.7721.969
Pressure (psi)102.900102.900102.900102.900102.900102.900102.900102.900102.900102.900
Length (ft)328.333328.333328.333328.333328.333328.333328.333328.333328.333328.333
Qty fluid flow (gals/min)0.0200.4851.9344.8389.62016.67426.36739.04555.03974.662
Coefficient C2.3149.97614.45817.63820.10522.12023.82425.30026.60227.767
Velocity V( ft/sec)0.2521.5332.7183.8234.8665.8576.8047.7158.5929.441
Bore dia (ft) D0.0160.0330.0490.0660.0820.0980.1150.1310.1480.164
EquivTtl head fluid h (ft)237.644237.644237.644237.644237.644237.644237.644237.644237.644237.644

Flow Rate of Fluids in Pipes

The quantity of fluid that will be discharged through a hose depends on the pressure applied at the feed end, the hose length and bore diameter. The surface character of the bore, the number, and shape of bends incorporated in the run of the hose also influence the flow rate.

The pressure is sometimes stated as ‘head of water’. If the head is given in metres of water, each 1-metre head (3.28 ft) induces 0.1 bar (1.47 psi.) pressure.

All formulae for finding the amount of fluid that will flow through a hose at a given time, are approximate. The graphs above are generated from calculations assuming the hose to be in good condition and laid in a straight line. With this being the case, they will be accurate to within 10% of the actual results obtained.

If the set of conditions entered in the model generate negative answers, then clearly it is necessary to adjust the variables as appropriate until a realistic result is obtained.

Caution: Ensure the hose selected is suitable for working at the design pressure selected.