Find another flow measurement calculator by clicking on the required answer which coincides with the input parameters you already know.

vol flow | mass flow | flow speed | vol | mass | time | |
---|---|---|---|---|---|---|

area |
flow speed | vol flow | ||||

dia |
flow speed | vol flow | ||||

w x h |
flow speed | vol flow | ||||

time |
vol | mass | vol flow | mass flow | ||

vol |
time | density | vol flow | |||

mass |
time | density | mass flow | |||

density |
mass flow | vol flow | mass | vol | ||

flow speed |
area, dia |

- Calculate volumetric flow rate from flow velocity and pipe diameter
- Calculate duct diameter from flow velocity and volume flow rate
- Calculate mass flow rate from volumetric flow rate and density
- Convert volumetric flow rates to other units
- Convert diameter into to other units
- Convert flow speed to other units

## User Guide

This tool will calculate the flow velocity in any units from the specified volumetric flow rate of a substance flowing through a round duct or pipe of a chosen diameter. For each new calculation a unique conversion scale will be generated for the range of volumetric flow rates and flow speeds for the diameter specified.

### Formula

The flow velocity formula used by this calculator is:

v = Q / (π · (ø / 2)²)

Derived from:

v = Q / A

A = π · r²

r = ø / 2

#### Symbols

- Q = Volume flow rate
- v = Flow velocity
- A = Cross-sectional area
- r = Radius
- ø = Diameter

n.b. This formula assumes uniform flow conditions within the entire cross-sectional area of pipe, without any friction losses near to surfaces.

### Volumetric Flow Rate Measured

Enter the volumetric amount of substance that will flow pass in a unit of time.

### Diameter

Enter the inside diameter of the circular pipe or duct.

### Flow Velocity Calculation

This is the speed at which the substance is moving.