Reynolds number and declared pipe regime
Enter your own density, viscosity and geometry.
- Runs in your browser
- No upload
- Check before download
Enter your own density, viscosity and geometry. For a circular pipe, the teaching profile treats Re below 2000 as laminar, 2000 to 3000 as an uncertain transition and above 3000 as turbulent. For other shapes, the tool gives Re without a pipe flow regime, or a flow rate when the area is unknown. It is not an approval for flow design.
Model, grammar and limits
Re=ρvD/μ=vD/ν; Q=πD²v/4
Numbers can have up to 48 characters, with a decimal point or e, and no thousands separators. Curves use 2 to 501 samples plus up to 16 section endpoints. Use up to 32 forces or sources and up to 16 sections. Springs take 1 to 20 periods with at least 8 samples per period; pendulum angles run from 0 to 179°. Magnus covers −40 to 35 °C over water and −40 to 0 °C over ice; relative humidity 0 to 100%, pressure 5 to 200 kPa, and vapor pressure must be below total pressure. Backup is limited to 1 MiB. Invalid, non-unique or unresolved data are rejected.
Results are numerical idealizations in SI units, shown with up to 10 digits; CSV keeps the numeric values and units. 9.80665 m/s² is the conventional standard g, not local gravity. Uncertainty in your inputs or the model is not estimated, and nothing here is a physical approval.
Calculation and backup stay in this browser. Workers stop after 15 seconds, or when you edit, reset or cancel. Inputs are never uploaded or stored. Input data, formulas and filenames are never sent. Only with your optional consent, Refentra sends aggregate counts of actions and outcomes, without input content.
Use the chosen model
- Model, grammar and limits
Enter your own density, viscosity and geometry. For a circular pipe, the teaching profile treats Re below 2000 as laminar, 2000 to 3000 as an uncertain transition and above 3000 as turbulent. For other shapes, the tool gives Re without a pipe flow regime, or a flow rate when the area is unknown. It is not an approval for flow design.
- Calculate
Re=ρvD/μ=vD/ν; Q=πD²v/4. Numbers can have up to 48 characters, with a decimal point or e, and no thousands separators. Curves use 2 to 501 samples plus up to 16 section endpoints. Use up to 32 forces or sources and up to 16 sections. Springs take 1 to 20 periods with at least 8 samples per period; pendulum angles run from 0 to 179°. Magnus covers −40 to 35 °C over water and −40 to 0 °C over ice; relative humidity 0 to 100%, pressure 5 to 200 kPa, and vapor pressure must be below total pressure. Backup is limited to 1 MiB. Invalid, non-unique or unresolved data are rejected.
- Download CSV report
Results are numerical idealizations in SI units, shown with up to 10 digits; CSV keeps the numeric values and units. 9.80665 m/s² is the conventional standard g, not local gravity. Uncertainty in your inputs or the model is not estimated, and nothing here is a physical approval. Calculation and backup stay in this browser. Workers stop after 15 seconds, or when you edit, reset or cancel. Inputs are never uploaded or stored. Input data, formulas and filenames are never sent. Only with your optional consent, Refentra sends aggregate counts of actions and outcomes, without input content.
Model questions
Model, grammar and limits
Enter your own density, viscosity and geometry. For a circular pipe, the teaching profile treats Re below 2000 as laminar, 2000 to 3000 as an uncertain transition and above 3000 as turbulent. For other shapes, the tool gives Re without a pipe flow regime, or a flow rate when the area is unknown. It is not an approval for flow design. Re=ρvD/μ=vD/ν; Q=πD²v/4
Unit
Flow geometry profile; Diameter/characteristic length; Speed; Density; Viscosity input; Dynamic viscosity; Kinematic viscosity. Numbers can have up to 48 characters, with a decimal point or e, and no thousands separators. Curves use 2 to 501 samples plus up to 16 section endpoints. Use up to 32 forces or sources and up to 16 sections. Springs take 1 to 20 periods with at least 8 samples per period; pendulum angles run from 0 to 179°. Magnus covers −40 to 35 °C over water and −40 to 0 °C over ice; relative humidity 0 to 100%, pressure 5 to 200 kPa, and vapor pressure must be below total pressure. Backup is limited to 1 MiB. Invalid, non-unique or unresolved data are rejected.
Model results
Results are numerical idealizations in SI units, shown with up to 10 digits; CSV keeps the numeric values and units. 9.80665 m/s² is the conventional standard g, not local gravity. Uncertainty in your inputs or the model is not estimated, and nothing here is a physical approval.
Download input backup
Calculation and backup stay in this browser. Workers stop after 15 seconds, or when you edit, reset or cancel. Inputs are never uploaded or stored. Input data, formulas and filenames are never sent. Only with your optional consent, Refentra sends aggregate counts of actions and outcomes, without input content.