Pump Head & Pressure
Hydraulic Head Conversions
Pressure to Head
Pump Head
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Head to Pressure
Pressure
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Hydraulic Power
Hydraulic Power
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Head & Pressure Relationships
Pressure to Head Conversion
H = P / (ρ × g)
H = Hydraulic head (m)
P = Pressure (Pa)
ρ = Fluid density (kg/m³)
g = Gravitational acceleration (9.81 m/s²)
P = Pressure (Pa)
ρ = Fluid density (kg/m³)
g = Gravitational acceleration (9.81 m/s²)
Head to Pressure Conversion
P = H × ρ × g
Inverse relationship: pressure is the hydrostatic load exerted by a column of fluid at height H
Common Reference Pressures
1 bar = 10.2 m head of water (at 1000 kg/m³, g=9.81)
1 psi = 0.703 m head of water
1 atm = 10.33 m head of water (standard)
1 atm = 760 mmHg
1 psi = 0.703 m head of water
1 atm = 10.33 m head of water (standard)
1 atm = 760 mmHg
Pump Power from Head & Flow
P = Q × ρ × g × H / 1000
P = Power (kW)
Q = Volumetric flow (m³/s)
ρ = Fluid density (kg/m³)
H = Total head (m)
Q = Volumetric flow (m³/s)
ρ = Fluid density (kg/m³)
H = Total head (m)
Hydraulic Power from Flow & Pressure
P = Q × ΔP / 1000
P = Hydraulic power (kW)
Q = Volumetric flow rate (m³/s)
ΔP = Pressure difference or system pressure (Pa)
Alternative (using head):
P (kW) = Q (m³/s) × ρ (kg/m³) × g (m/s²) × H (m) / 1000
Q = Volumetric flow rate (m³/s)
ΔP = Pressure difference or system pressure (Pa)
Alternative (using head):
P (kW) = Q (m³/s) × ρ (kg/m³) × g (m/s²) × H (m) / 1000
Power Conversions
| From | To | Multiply by |
|---|---|---|
| kW | hp | 1.3410 |
| hp | kW | 0.7457 |
| kW | W | 1000 |