Fluid Calculator

  • Water Viscosity Calculator
    Calculate the dynamic viscosity of water at any temperature using the Vogel relation. Get results in Pa·s, mPa·s and centipoise (cP) instantly.
  • Water Pressure at Depth Calculator
    Calculate hydrostatic water pressure at any depth using P = P_atm + ρgh. Get absolute and gauge pressure in Pa, kPa and atmospheres instantly.
  • Stokes' Law Calculator
    Calculate the terminal settling velocity of a spherical particle in a fluid using Stokes' Law from density, radius, viscosity and gravity.
  • Prandtl Number Calculator
    Calculate the Prandtl number (Pr) from specific heat, dynamic viscosity, and thermal conductivity. Free dimensionless heat-transfer calculator with worked example.
  • Reynolds Number Calculator
    Calculate the Reynolds number from fluid density, velocity, characteristic length and viscosity to determine laminar, transitional or turbulent flow.
  • Prandtl-Meyer Expansion Calculator
    Compute the Prandtl-Meyer function ν(M) for supersonic expansion flow from Mach number and specific heat ratio γ, with the Mach angle output.
  • Pounds per Minute Calculator
    Calculate mass flow rate in pounds per minute (lb/min) by dividing total mass in pounds by elapsed time in minutes. Fast, free, and accurate.
  • Poiseuille's Law Calculator
    Calculate the volumetric flow rate of a viscous fluid through a cylindrical pipe using Poiseuille's Law from pressure, radius, viscosity, and length.
  • Pipe Flow Calculator
    Calculate the volumetric flow rate of a fluid through a round pipe from its inner diameter and velocity using Q = (π/4)·d²·v. Results in m³/s, L/s and m³/h.
  • Pipe Velocity Calculator
    Calculate fluid velocity inside a pipe from flow rate and inside diameter. Supports m³/s, m³/h, L/s and L/min with instant results.
  • Orifice Flow Calculator
    Calculate volumetric flow through an orifice using Q = Cd·A·√(2gh). Enter discharge coefficient, area, head and gravity to get flow rate in m³/s.
  • Manometer Pressure Calculator
    Calculate manometer pressure from fluid column height using P = ρgh. Get results in Pa, kPa, bar, mmHg, and psi instantly.
  • Mach Number Calculator
    Calculate Mach number from object speed and speed of sound using M = v/a. Get the Mach value and flow regime (subsonic, supersonic, hypersonic).
  • Knudsen Number Calculator
    Calculate the Knudsen number (Kn = λ / L) from mean free path and characteristic length, and identify the flow regime: continuum, slip, transitional, or free molecular.
  • Hydrostatic Pressure Calculator
    Calculate hydrostatic pressure with P = ρgh from fluid density, gravity, and depth. Get results in Pa, kPa, bar, and atmospheres instantly.
  • Hydraulic Radius Calculator
    Calculate hydraulic radius (Rh) from cross-sectional area and wetted perimeter using Rh = A / P. Free, instant open-channel flow calculator.
  • Hydraulic Pressure Calculator
    Calculate hydraulic pressure from force and piston area using P = F / A. Get results in pascals, kPa, bar, and psi instantly.
  • Hydraulic Gradient Calculator
    Calculate the hydraulic gradient (i = dh / L) from head loss and flow path length. Free dimensionless gradient and percent slope calculator for groundwater flow.
  • Darcy's Law Calculator
    Calculate groundwater volumetric flow rate using Darcy's law: Q = K·A·(dh/dL). Enter hydraulic conductivity, area, head difference and path length.
  • Darcy-Weisbach Head Loss Calculator
    Calculate pipe friction head loss with the Darcy-Weisbach equation. Enter friction factor, length, diameter, velocity and gravity to get head loss in meters.
  • Differential Pressure Calculator
    Calculate differential pressure (ΔP) as the difference between upstream and downstream pressure. Supports psi, bar, kPa, Pa, mmHg and inH2O.
  • Broad-Crested Weir Flow Calculator
    Compute discharge Q over a broad-crested weir from coefficient, crest width, head and gravity using Q = Cd·b·√g·(2/3)^(3/2)·H^(3/2).
  • Hydraulic Conductivity Calculator
    Calculate hydraulic conductivity K from flow rate, sample length, cross-sectional area, and head difference using Darcy's law. Free online tool.
  • Drag Force Calculator
    Calculate aerodynamic drag force using the drag equation Fd = ½·ρ·v²·Cd·A. Enter fluid density, velocity, drag coefficient and area for instant results.

Categories