🌊 Fluids – Dynamics (Hydrodynamics)

Continuity, Bernoulli, viscosity, flow rate, Reynolds number

A₁v₁ = A₂v₂ Bernoulli Viscosity Reynolds
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💡 Fluid dynamics

Fluid dynamics (hydrodynamics) studies fluids in motion. Continuity equation: mass conservation (A₁v₁ = A₂v₂). Bernoulli's equation: energy conservation (P + ½ρv² + ρgh = constant). Viscosity resists flow. Reynolds number determines flow type (laminar vs turbulent).

Fluid dynamics calculators

Continuity, Bernoulli, viscosity, flow, Reynolds

Area 1 (A₁)
Velocity 1 (v₁)
Area 2 (A₂)
Velocity 2
4.00 m/s
Pressure 1 (P₁)
Velocity 1 (v₁)
Height 1 (h₁)
Velocity 2 (v₂)
Height 2 (h₂)
Density (ρ)
Pressure 2
87.4 kPa
Viscosity (η)
Radius (r)
Velocity (v)
Drag Force (Stokes)
1.88×10⁻⁵ N
Radius (r)
Pressure difference (ΔP)
Viscosity (η)
Length (L)
Flow Rate (Q)
3.93×10⁻⁶ m³/s
Density (ρ)
Velocity (v)
Diameter (D)
Viscosity (η)
Reynolds Number
20000

🌊 Fluid dynamics visualization

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Concept Formula Notes / Units / Conditions
Continuity Equation A₁ v₁ = A₂ v₂ Incompressible fluid → A v = constant
Bernoulli's Equation P + ½ ρ v² + ρ g h = constant Along a streamline; ideal fluid (no viscosity)
Torricelli's theorem v = √(2 g h) Speed of efflux from hole at depth h
Viscosity (Newtonian) F = η A (dv/dx) η = coefficient of viscosity (Pa·s)
Stokes' Law F_d = 6πη r v Laminar flow, small sphere
Poiseuille's Law Q = (π r⁴ ΔP) / (8 η L) Volume flow rate; laminar flow
Reynolds number Re = ρ v D / η Re < 2000 → laminar; Re > 4000 → turbulent

About Fluid Dynamics

Fluid dynamics (hydrodynamics) studies fluids in motion. Key principles include mass conservation (continuity), energy conservation (Bernoulli), and flow resistance (viscosity).

Continuity Equation

Continuity equation: A₁v₁ = A₂v₂ for incompressible fluids. Mass conservation: flow rate is constant. Narrow pipe → faster flow; wide pipe → slower flow.

Bernoulli's Equation

Bernoulli's equation: P + ½ρv² + ρgh = constant along a streamline. High speed → low pressure (Venturi effect). Used for lift, flow measurement, and pressure calculations.

Viscosity and Flow

Viscosity (η) measures fluid resistance to flow. Stokes' law: F_d = 6πηrv for drag on sphere. Poiseuille's law: Q = (πr⁴ΔP)/(8ηL) for flow through tube.

Reynolds Number

Reynolds number Re = ρvD/η determines flow type. Re < 2000 → laminar (smooth), Re > 4000 → turbulent (chaotic). Dimensionless parameter for flow characterization.