The way that the formula for Reynolds Number is usually expressed requires that all the parameters are expressed in consistent units. However, in practice it is uncommon for the data to all be in a consistent set of units and often the flow data is available as a mass or volumetric flowrate rather than a velocity. The Reynolds Number calculator in Uconeer will allow any mix of units and you can select the form of flowrate that you have available. In addition, the calculator allows the use of kinematic viscosity if that is what you have available.
When you select any one of Velocity, Mass Flowrate or Volumetric Flowrate as the input data, the calculator will automatically calculate the other two. This is a useful conversion in itself as it is often required to calculate a fluid velocity from a flowrate (or vice versa) for a given pipe size.