Fluid Mechanics
Flow Rate Calculator
Volumetric flow rate from pipe area and velocity (Q = A·v), in m³/s, L/min and gallons per minute.
Q = A × v = volume ÷ time
Also called volumetric flow rate · q = av
Science · 10 calculators
Fluid Mechanics Calculators
Flow rate, fluid velocity, pressure, Bernoulli's equation, Reynolds number, pipe flow, hydraulics, buoyancy and viscosity.
Fluid Mechanics
Fluid Velocity Calculator
Fluid velocity in a pipe from flow rate and diameter, with the continuity equation for size changes.
v = Q / A
Also called pipe velocity · water velocity
Fluid Mechanics
Pressure Calculator
Pressure from force and area (P = F/A) or fluid depth (P = ρgh), in Pa, bar, psi and atm.
P = F / A
Also called pressure formula · p = f/a
Fluid Mechanics
Bernoulli's Equation Calculator
Pressure, velocity and height relationship in a flowing fluid using Bernoulli's principle.
P₁ + ½ρv₁² + ρgh₁ = P₂ + ½ρv₂² + ρgh₂
Also called bernoulli principle · fluid pressure velocity
Fluid Mechanics
Reynolds Number Calculator
Reynolds number for pipe flow and whether the flow is laminar, transitional or turbulent.
Re = ρvD / μ
Also called re number · laminar or turbulent
Fluid Mechanics
Pipe Flow Calculator
Flow rate, velocity and pressure loss in a pipe using the Hazen-Williams equation.
Hazen-Williams: h_f = 10.67·L·Q^1.852 / (…
Also called pipe flow rate · hazen williams
Fluid Mechanics
Hydraulic Press Calculator
Pascal's law: output force, pressure and piston travel for a hydraulic press or jack.
F₂ = F₁ × A₂ / A₁ (pressure is equal thro…
Also called pascal law calculator · hydraulic force
Fluid Mechanics
Buoyancy Calculator
Archimedes' principle: buoyant force, apparent weight and whether an object floats or sinks.
F_b = ρ_fluid × g × V_displaced
Also called archimedes principle · buoyant force
Fluid Mechanics
Density Calculator
Density, mass or volume (ρ = m/V) — with the result also in g/cm³ and lb/ft³.
ρ = m / V
Also called density formula · mass volume density
Fluid Mechanics
Viscosity Calculator
Convert between dynamic and kinematic viscosity, in Pa·s, poise, cSt and SSU.
ν = μ / ρ
Also called kinematic viscosity · dynamic viscosity
Key fluid mechanics formulas
| Flow Rate | Q = A × v = volume ÷ time |
|---|---|
| Fluid Velocity | v = Q / A · A₁v₁ = A₂v₂ |
| Pressure | P = F / A · P = ρgh |
| Bernoulli's Equation | P₁ + ½ρv₁² + ρgh₁ = P₂ + ½ρv₂² + ρgh₂ |
| Reynolds Number | Re = ρvD / μ |
| Pipe Flow | Hazen-Williams: h_f = 10.67·L·Q^1.852 / (C^1.852·d^4.87) |
| Hydraulic Press | F₂ = F₁ × A₂ / A₁ (pressure is equal throughout) |
| Buoyancy | F_b = ρ_fluid × g × V_displaced |
| Density | ρ = m / V |
| Viscosity | ν = μ / ρ |