# Volumetric Flow Rate - 5W1H

Updated: Nov 5

**What is volumetric flow rate?**

The volumetric flow rate is volume displaced per unit time and it is expressed as

**Why use volumetric flow rate? **

It is a measure of the quantity of the fluid that is being displaced from one place to other.

This is an important parameter when designing pumps, compressors, turbines, piping systems, heat exchangers, etc

**What are the units of volumetric flow rate? **

In the metric system of units,

In the metric/english system of units,

**What is the difference between mass flow rate and volume flow rate?**

The mass flow rate is nothing but a multiplication of volume flow rate with the density of the fluid. It is expressed in kg/s in metric units.

**Why is the volumetric flow rate not a conserved quantity?**

If the fluid is compressible then the volume flow rate may change from place to place with respect to temperature and pressure (in the case of compressors) and it may not be conserved as the density may vary. The mass flow rate is always(and must) a conserved quantity but the volume flow rate is not.

**How to calculate the volume flow rate?**

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