💧 Hydraulics & Hydrology Calculators
15 calculators available
Hydraulics and hydrology are essential disciplines for water resource engineering, drainage design, and fluid mechanics applications. Our calculators cover pipe flow analysis using the Hazen-Williams equation, open channel flow with Manning's equation, energy conservation with Bernoulli's equation, stormwater estimation using the Rational Method, and friction head loss calculation with the Darcy-Weisbach equation.
Available Calculators
Bernoulli Equation Calculator
The Bernoulli Equation Calculator applies the energy equation between two points in a flow system, solving for the downstream pressure from the upstream conditions, velocity change, elevation change and head loss.
Catchment Runoff Calculator
The Catchment Runoff Calculator computes storm runoff depth and volume using the SCS Curve Number method, from rainfall depth, curve number and catchment area.
Culvert Design Calculator
The Culvert Design Calculator computes the full-bore capacity and velocity of a circular culvert under outlet control, and the diameter required for a given design flow.
Froude Number Calculator
The Froude Number Calculator classifies open channel flow as subcritical, critical or supercritical, and returns the critical depth and specific energy.
Head Loss Calculator
The Head Loss Calculator determines friction head loss in a pipe using the Darcy-Weisbach equation, and converts it into pressure drop, loss per metre and the pumping power required to overcome it.
Manning's Equation Calculator
The Manning's Equation Calculator determines the flow velocity and discharge in a rectangular open channel from its dimensions, slope and roughness coefficient.
NPSH Calculator
The NPSH Calculator determines the net positive suction head available at a pump, the margin over its requirement, and the maximum suction lift the system can sustain.
Open Channel Velocity Calculator
The Open Channel Velocity Calculator computes velocity, discharge and Froude number for a trapezoidal channel using Manning's equation.
Orifice Flow Calculator
The Orifice Flow Calculator determines the discharge through a small orifice under a given head, using Torricelli's theorem with a discharge coefficient.
Pipe Flow Calculator
The Pipe Flow Calculator determines flow velocity, cross-sectional area, Reynolds number and flow regime for a circular pipe running full, from the flow rate, diameter and fluid viscosity.
Rainfall-Runoff Calculator
The Rainfall-Runoff Calculator determines peak stormwater discharge from a catchment using the Rational Method, along with the rainfall and runoff volumes over one hour.
Reynolds Number Calculator
The Reynolds Number Calculator determines whether pipe flow is laminar, transitional or turbulent, and returns the corresponding Darcy friction factor.
Settling Velocity Calculator
The Settling Velocity Calculator determines how fast a particle settles in a fluid, using Stokes' law and correcting it with an iterative drag solution beyond its valid range.
Water Hammer Calculator
The Water Hammer Calculator determines the surge pressure from rapid valve closure using the Joukowsky equation, with the critical closure time and relief for slower closure.
Weir Flow Calculator
The Weir Flow Calculator determines discharge over a rectangular sharp-crested weir, applying the Francis correction for end contractions.
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About Hydraulics Engineering
Calculate pipe flow rates, open channel flow using Manning's equation, pressure head with Bernoulli's equation, rainfall-runoff, and head loss in piping systems.
Frequently Asked Questions
What is Manning's equation used for?
Manning's equation calculates the velocity and flow rate in open channels such as rivers, canals, and storm sewers. It uses the channel's hydraulic radius, slope, and roughness coefficient (n) to determine flow characteristics.
What is Bernoulli's equation?
Bernoulli's equation relates pressure, velocity, and elevation in a flowing fluid. It states that the total mechanical energy per unit volume remains constant along a streamline: P + ½ρv² + ρgh = constant.
How do you calculate head loss in a pipe?
Head loss due to friction in a pipe is calculated using the Darcy-Weisbach equation: hf = f × (L/D) × (v²/2g), where f is the friction factor, L is pipe length, D is pipe diameter, v is flow velocity, and g is gravitational acceleration.