fluid mechanics Calculators
Last updated: May 2026
Reynolds Number Calculator
Compute the Reynolds number to determine whether pipe or channel flow is laminar, transitional, or turbulent.
Darcy-Weisbach Pressure Loss Calculator
Compute friction pressure loss in a pipe using the Darcy-Weisbach equation, the rigorous standard for all Newtonian fluids and flow regimes.
Bernoulli's Equation Calculator
Compute the total mechanical energy per unit volume of a flowing fluid at a point by summing static pressure, kinetic pressure, and elevation head.
Manning's Roughness Flow Calculator
Estimate average flow velocity in an open channel or partially-full pipe using Manning's equation with hydraulic radius, slope, and roughness coefficient.
Hazen-Williams Flow Calculator
Estimate water flow velocity and discharge in a pressurized pipe using the empirical Hazen-Williams equation.
Venturi Meter Flow Calculator
Determine the volumetric flow rate of a fluid passing through a venturi meter.
Orifice Flow Rate Calculator
Compute the volumetric flow rate of a liquid discharging through a circular orifice under a given hydraulic head.
Pump Power Calculator
Calculate the shaft power a pump must deliver to move fluid through a system against a given total head.
Pipe Flow Velocity Calculator
Find the average velocity of fluid flowing inside a circular pipe from the volumetric flow rate and pipe diameter.
Hydrostatic Pressure Calculator
Calculate the absolute pressure at any depth in a stationary fluid, accounting for atmospheric pressure at the surface.
Pipe Friction Loss Calculator
Estimate the pressure head lost to friction in any pipe system using the Darcy-Weisbach equation.
Tank Drain Time Calculator
Calculate how long it takes to drain a tank from one liquid level to another through a bottom orifice.
Pipe Sizing Calculator
Find the minimum required pipe diameter to keep fluid velocity within safe limits for a given flow rate.
Weir Flow Calculator
Calculate the volumetric flow rate of water passing over a weir based on weir width, upstream head, and weir type.
Pump Affinity Laws Calculator
Predict how a centrifugal pump's flow rate, head, and power change when its speed is varied using the pump affinity laws.
Pipe Flow Calculator
Determine pressure drop in circular pipes using the Darcy-Weisbach equation.
Reynolds Number Calculator
Compute the Reynolds number to classify fluid flow as laminar, transitional, or turbulent.
Pump Power Calculator
Calculate the shaft power and motor input power needed to pump a fluid against a given head.
Orifice Flow Calculator
Calculate volumetric flow rate through an orifice plate or sharp-edged opening given pressure drop and fluid properties.
Open Channel Flow Calculator
Compute flow rate and velocity in open channels — rivers, ditches, and culverts — using Manning's equation.
Hydraulic Jump Calculator
Compute sequent depth, energy loss, and Froude number for a hydraulic jump in an open channel.
Venturi Meter Calculator
Determine the volumetric flow rate through a pipe using upstream and throat pressure readings from a Venturi meter.
Friction Factor Calculator
Find the Darcy-Weisbach friction factor for laminar or turbulent pipe flow from the Reynolds number and pipe roughness.
Bernoulli Equation Calculator
Solve Bernoulli's equation to find downstream pressure in a flowing fluid given upstream conditions, elevation change, and system losses.
Weir Flow Calculator
Calculate volumetric flow rate over rectangular, triangular, or trapezoidal weirs from the head of water above the weir crest.
Darcy-Weisbach Pressure Drop Calculator
Calculates pressure drop along a pipe section using the Darcy-Weisbach equation.
Pipe Flow Reynolds Number Calculator
Computes the Reynolds number for flow inside a pipe to classify the flow as laminar, transitional, or turbulent.
Pump Power and Efficiency Calculator
Calculates the shaft power a pump must deliver to move fluid against a given head, accounting for pump efficiency.
Orifice Flow Discharge Calculator
Calculates the volumetric flow rate through an orifice plate or opening given the upstream-to-downstream pressure difference.
Hydraulic Jump Depth Calculator
Calculates the sequent (conjugate) depth downstream of a hydraulic jump in open channel flow.
Weir Flow Discharge Calculator
Estimate volumetric flow rate (discharge) over a weir structure given its width, head height, and discharge coefficient.
Pipe Network Flow Distribution Calculator
Distribute flow between two parallel pipes based on their diameters, lengths, and roughness using Hardy-Cross principles.
Manning's Equation Open Channel Calculator
Compute flow velocity and discharge in open channels — rivers, canals, and drains — using Manning's equation.
Hazen-Williams Flow Rate Calculator
Calculate water flow rate in pressurised pipes using the Hazen-Williams equation given pipe diameter, hydraulic gradient, and C factor.
Pump Affinity Laws Calculator
Predict how a centrifugal pump's flow, head, and power change when its speed or impeller size is altered, using the pump affinity laws.
Water Hammer Pressure Calculator
Calculates the pressure surge caused by sudden valve closure or rapid flow changes in a pipe.
Hydraulic Jump Calculator
Analyzes hydraulic jump characteristics in open channel flow, including sequent depth, energy loss, and jump length.