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Mass flow rate vs Volumetric flow rate is what we must use in flow measurement and control. In this post, we compare the concept of volume flow and mass flow and the conversion between the two.

Commonly used flow meters, such as orifice plates. Turbine flowmeter. Vortex flowmeter. Electromagnetic Flowmeter. Rotameter. The flow measurement value of ultrasonic flowmeter and oval gear flowmeter is the volume flow of fluid. Coriolis mass flow meters and thermal gas mass flow meters measure mass flow.

Sino-Inst offers a variety of  volume flow and mass flow meters for flow measurement. If you have any questions, please contact our sales engineers.

## What is Flow Rate?

Flow rate refers to the ratio of the amount of fluid flowing through the cross-section of the pipe to the time it takes for that amount to pass through the cross-section. Flow is divided into volume flow and mass flow.

## What is volume flow?

The volume flow rate is the flow rate expressed by the volume of the fluid quantity.
The volume flow is expressed by the formula: qv=V/t=u×A.
In the formula: qv is the volume flow, m3/s.
V is the unit flow volume, m3.
t is the unit time, s.
u is the average flow velocity in the pipe, m/s.
A is the cross-sectional area of ​​the pipeline, m2.

Among the commonly used flow meters, such as orifice plates, turbine flow meters, vortex flow meters, electromagnetic flow meters, rotameters, ultrasonic flow meters and oval gear flow meters, the flow measurement value is the volume flow of the fluid.

Featured Volume Flow Meters

## What is mass flow?

Mass flow rate refers to the flow rate of fluid quantity expressed by mass.
The mass flow rate can be expressed by the formula: qm=m/t=ρ×u×A.
In the formula, qm is the mass flow rate, kg/s.
m is the unit fluid mass, kg.
ρ is the fluid density, kg/m3.
t is the unit time, s.
u is the average flow velocity in the pipe, m/s.
A is the cross-sectional area of ​​the pipeline, m2.

Featured Mass Flow Meters

## Mass Flow Rate vs Volumetric Flow Rate-How to convert ?

1. If the mass flow of the flow is known and needs to be converted into volume flow, the following formula can be used: qv=qm/ρ. In the formula, qv is volume flow, m3/s. qm is mass flow, kg/s. ρ is fluid Density, kg/m3.
2. If the volume flow rate of the fluid is known, it needs to be converted into a mass flow rate, which can be done with the formula: qm=qv×ρ.

## Density, Mass Flow, and Volumetric Flow

A description on the relationship between density, mass flow rate and volumetric flow rate. The following video provides a good explanation.