Hydraulic Pressure Drop & Power Calculator

Last updated: 31 Jul 2025 | Author: Brij | Review By: Irshad

Share on :

Use our Hydraulic Pressure Drop & Power Calculator to compute flow velocity, pressure drop, and required pump power from flow rate, pipe diameter, and friction factor.

Flow Rate:

Pipe Diameter:

Pipe Length:

Fluid Density (kg/m³):

Friction Factor:

Hydraulic Results

Flow Velocity:

Pressure Drop:

Pump Power:

The Hydraulic Pressure Drop & Power Calculator helps determine the pressure losses in a fluid system and calculates the power required to overcome these losses. It uses the Darcy-Weisbach equation, which is widely accepted in fluid dynamics for calculating pressure drop due to friction in pipes.

Formulas Used

1. Flow Velocity (V)

The flow velocity is determined by dividing the volumetric flow rate by the cross-sectional area of the pipe:

$V = \frac{Q}{A}$

Where:

$V$ = Flow velocity (m/s)
$Q$ = Flow rate (m³/s)
$A$ = Cross-sectional area of the pipe (m²)

2. Cross-Sectional Area of Pipe (A)

$A = \pi \left( \frac{D}{2} \right)^2$

Where:

$D$ = Pipe diameter (m)

3. Pressure Drop ( $\Delta P$ )

Using the Darcy-Weisbach equation:

$\Delta P = f \cdot \frac{L}{D} \cdot \frac{\rho V^2}{2}$

Where:

$\Delta P$ = Pressure drop (Pa)
$f$ = Friction factor (Darcy)
$L$ = Pipe length (m)
$D$ = Pipe diameter (m)
$\rho$ = Fluid density (kg/m³)
$V$ = Flow velocity (m/s)

4. Pump Power (P)

$P = Q \cdot \Delta P$

Where:

$P$ = Power (W)
$Q$ = Flow rate (m³/s)
$\Delta P$ = Pressure drop (Pa)

Example Calculation

Given:

Flow rate $Q$ = $10 \, \text{GPM}$
Pipe diameter $D$ = $2 \, \text{in}$
Pipe length $L$ = $100 \, \text{ft}$
Fluid density $ρ$ = $1000 \, \text{kg/m}^3$
Friction factor $f$ = 0.02

Step 1: Convert Units

10 GPM = $0.000631 \, \text{m}^3/\text{s}$
2 $\text{in} = 0.0508 \, \text{m}$
100 $\text{ft} = 30.48 \, \text{m}$

Step 2: Calculate Area

$A = \pi \left( \frac{0.0508}{2} \right)^2 = 0.002026 \, m^2$

Step 3: Calculate Velocity

$V = \frac{0.000631}{0.002026} = 0.311 \, m/s$

Step 4: Calculate Pressure Drop

$\Delta P = 0.02 \cdot \frac{30.48}{0.0508} \cdot \frac{1000 \cdot 0.311^2}{2} = 588.4 \, Pa$

Step 5: Calculate Power

$P = 0.000631 \cdot 588.4 = 0.371 \, W$

Check out 1 similar Hydraulic Pressure Drop & Power Calculator :

Hydraulic Pressure Drop & Power Calculator

Help Improve This Calculator

Your suggestions help us make better tools for everyone.