An insertion gas flow meter is used to measure the flow rate of gases or air. A flow meter measures the amount of gas or liquid flowing through a pipeline and determines the flow which is equivalent to the velocity of the fluid and the cross-sectional area of the pipe.
There are approximately 6-8 flow measurement instruments for measuring the flow rate of gases available. However, the accuracy and rangeability of the devices is different depending on various factors such as the composition of the gas. Large pipeline gas flow meters are usually insertion thermal mass flow meter because they are suitable for measuring the flow rate of different kinds of gases.
Insertion Thermal Mass Gas Flow Meter Principle
An insertion thermal mass gas flow meter uses heat transfer to measure the gas flow rate. By heating one of the sensors of the thermal mass gas flow meter, the heated sensor becomes the flow sensor while a second sensor is maintained at a constant temperature to act as a reference point.
When the gas flows through the heated sensor, they take heat away from the sensor and these cools down the sensor’s temperature. This creates a temperature difference between the heated sensor and the reference sensor. To restore energy, the flow sensor is heated again and the mass flow signal is given by the electrical power needed to maintain the heat of the flow sensor.
Thermal dispersion flow meter calculates the mass rather than the volume of the gas. The main principle used by thermal mass gas flow meter is convection. This is because the flow is measured by detecting the temperature rise created when gas flows through the heated sensor.
Insertion thermal flow sensor Features
Various features make insertion thermal mass gas flow meter applicable for industrial uses. Some of these key features include:
They have no moving parts this makes it easy to maintain since there is low risk of damage or wear and tear. Lacking moving parts also makes insertion thermal mass gas flow meters in a wide range of areas including measuring the flow of saturated gas.
They have an unobstructed flow path
They do not need any pressure or temperature alterations which makes them a low-cost device since there is no need for additional equipment once they have been installed.
They can retain a high level of accuracy in varying flow rates which makes them suitable for use in both large and small pipes.
Insertion thermal mass gas flow meters measure the mass flow instead of the volumetric flow and this makes them more reliable and gives them wide rangeability. The mass flow remains constant since it cannot be affected by density, pressure or viscosity.
Use Insertion Gas Flow Meter
Insertion thermal mass gas flow meters are commonly used to measure the flow rate of gases with a very low velocity. They can also be used to measure the flow rate of gases in a chemical reaction depends on the masses of the individual gases.