Resources, Tools and Basic Information for Engineering and Design of Technical Applications!
mobile - visible on handheld devices - alternatively go to www.engineeringtoolbox.com!
Engineering ToolBox > Water Flow in Tubes - Reynolds Number
Turbulent or laminar flow is determined by the dimensionless Reynolds Number.
The Reynolds number is important in analyzing any type of flow when there is substantial velocity gradient (i.e., shear.) It indicates the relative significance of the viscous effect compared to the inertia effect. The Reynolds number is proportional to inertial force divided by viscous force.
The flow is
The table below shows Reynolds Number for one liter of water flowing through pipes of different dimensions:
| Pipe Size | ||||||||||
| (inches) | 1 | 1 1/2 | 2 | 3 | 4 | 6 | 8 | 10 | 12 | 18 |
| (mm) | 25 | 40 | 50 | 75 | 100 | 150 | 200 | 250 | 300 | 450 |
| Reynolds number with one (1) liter/min | 835 | 550 | 420 | 280 | 210 | 140 | 105 | 85 | 70 | 46 |
| Reynolds number with one (1) gal/min | 3800 | 2500 | 1900 | 1270 | 950 | 630 | 475 | 380 | 320 | 210 |