Reynolds number calculator
laminar or turbulent flow
online since 2001
Additional features in download version
save/open resultsprint results
custom fluid properties
K factor for fittings, resistance coefficient
compressible isothermal flow
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Description
- q - volumetric flow rate
- Fluid flow rate in terms of units of volume per unit of time
- ṁ - mass flow rate
- Fluid flow rate in terms of units of mass per unit of time
- V - velocity
- Flow velocity in terms of units of distance per unit of time
- D - pipe diameter
- Internal circular pipe diameter
- H - channel height
- The height of channel for rectangle shaped pipe
- W - channel width
- The width of channel for rectangle shape pipe
- A - area
- Internal pipe cross section area
- ρ - fluid density
- Mass per unit of volume
- T - temperature
- Fluid temperature for gas density calculation based on the ideal gas state equation
- p - pressure
- Fluid pressure at the start of the pipe for gas density calculation based on the ideal gas state equation
- R - gas constant
- Gas constant in terms of energy per unit of mass and temperature, for gas density calculation using ideal gas state equation
- ν - kinematic viscosity
- Result of fluid particles colliding to each other and moving at different velocities in terms of area per square unit of time
- μ - dynamic viscosity
- Result of fluid particles colliding to each other and moving at different velocities in terms of mass per square unit of distance and time
- Re - Reynolds number
- Dimensionless number representing viscous versus inertial forces ratio
Calculation setup
- Select value to input. You should enter selected one. The other two will be calculated
- q
- volumetric flow rate
- ṁ
- mass flow rate
- V
- flow velocity
- Select value to input. You should enter selected one. The other one will be calculated. Available only if the gas is selected fluid
- ρ
- fluid density
- T
- temperature
- Select value to input. You should enter selected one. The other one will be calculated
- ν
- kinematic viscosity
- μ
- dynamic viscosity
- Select fluid type
- liquid
- for incompressible fluids
- gas
- for fluids where ideal gas state equation is used. Enables selection between density and temperature to input.
- Select pipe shape
- round pipe
- full cross section fluid flow
- rectangle pipe
- for rectangle channels and full cross section flow
