Pressure Drop Calculator

Overview

Engineering reference data for Pressure Drop Calculator in fluid mechanics.

Key Formulas

Reynolds Number

$Re = \frac{\rho v D}{\mu}$

Ratio of inertial to viscous forces — determines flow regime.

Bernoulli's Equation

$P + \frac{1}{2}\rho v^2 + \rho g h = \text{const}$

Conservation of energy for steady, inviscid, incompressible flow.

Continuity Equation

$A_1 v_1 = A_2 v_2$

Conservation of mass for incompressible flow.

Darcy-Weisbach

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

Pressure drop due to friction in a pipe.

Variables

Symbol	Description	Unit
$Re$	Reynolds number	—
$\rho$	Fluid density	kg/m³
$v$	Flow velocity	m/s
$D$	Characteristic dimension	m
$\mu$	Dynamic viscosity	Pa·s
$P$	Pressure	Pa
$f$	Darcy friction factor	—

Practical Applications

For quick engineering calculations, online tools can be valuable. The linked resource provides a convenient calculator for single-phase pressure drop in steel pipes:

Online Calculator: pipingnews.com/flowrate.htm

When to Use This Calculator

• For initial estimates during system design
• When pipe specifications match standard steel pipe dimensions
• For single-phase, incompressible fluid flow

Limitations to Consider

1. Material Specific: Results apply primarily to steel pipes
2. Flow Regime: May not account for all turbulent flow conditions
3. Fluid Properties: Assumes constant fluid properties along the pipe length

For critical engineering applications, always verify results against manual calculations using the Darcy-Weisbach equation and Moody diagram methodology outlined in the Key Formulas section.

References

• Original Source