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Both calculators run independently — change the inputs on either side to compare results.
Fluid Mechanics
Pump Power Calculator
Calculate the shaft power and motor input power needed to pump a fluid against a given head. Use this for selecting pump and motor sizes in water supply, irrigation, and industrial systems.
Fill in the required fields to see your result.
Fluid Mechanics
Weir Flow Calculator
Calculate the volumetric flow rate of water passing over a weir based on weir width, upstream head, and weir type. Used by civil engineers and hydrologists to measure or control open-channel flow in rivers, canals, and water treatment plants.
Fill in the required fields to see your result.
Key differences
| Pump Power Calculator | Weir Flow Calculator | |
|---|---|---|
| Category | Fluid Mechanics | Fluid Mechanics |
| Inputs required | 5 | 3 |
| Result | Required Power (kW) | Flow Rate (m³/s) |
| What it does | Calculate the shaft power and motor input power needed to pump a fluid against a given head. Use this for selecting pump and motor sizes in water supply, irrigation, and industrial systems. | Calculate the volumetric flow rate of water passing over a weir based on weir width, upstream head, and weir type. Used by civil engineers and hydrologists to measure or control open-channel flow in rivers, canals, and water treatment plants. |