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Factors Affecting Measurement Accuracy of Mass Flow Meters - Focus on Microfluidic Control Technology

The mass flow meter directly measures the mass flow rate of the medium passing through the flow meter, and also measures the density of the medium and indirectly measures the temperature of the medium. The mass flow meter cannot control the flow rate. It can only detect the mass flow of liquid or gas, and output the flow value by analog voltage, current or serial communication. The mass flow meter is flexible, powerful, and cost-effective. It is a new generation flow meter. The mass flowmeter is based on Coriolis force. There are two parallel flow tubes inside the sensor, the drive coil is installed in the middle, the detection coil is installed at both ends, and the excitation voltage provided by the transmitter is applied to the drive coil. Perform a reciprocating cycle of vibration. The mass flow meter is a relatively accurate, fast, reliable, efficient, stable and flexible flow measuring instrument, which has been widely used in petroleum processing, chemical industry and other fields.
The most remarkable feature of the mass flow meter is that it can directly measure the mass flow rate of the medium, without being affected by factors such as pressure and temperature of the working state of the medium. Factors affecting the accuracy of mass flowmeter measurement:
1. Environmental vibration impact
The mass flow meter can operate in a vibrating environment, but must be isolated from vibration, such as a flexible tube connected to the vibrating tube and a support frame that isolates vibration. However, it should be prevented that the vibration frequency is the same as the operating frequency or harmonic frequency of the mass flowmeter. Multiple instruments of the same model are installed in series or in parallel, especially on the same support gantry. The vibration of the working frequency between the mass flow meters will affect each other, causing abnormal vibration, which will make the instrument inoperable in severe cases. When ordering, it can be specially proposed to the manufacturer to stagger the working frequency of the two series mass flow meters.
2, fluid density impact
The change in fluid density changes the mass of the flow measurement system, causing the balance of the mass flow meter sensor to change, resulting in a zero offset. If a particular liquid is measured, as long as it is zeroed under the actual density of the liquid used, the density during use does not change much, and generally there is no problem. However, when measuring several liquids with large differences in density on one pipe, there is an additional error of zero point variation.
3, fluid viscosity effect
Mass flow meters measure a wide range of liquid viscosities and exhibit good measurement performance. Although there are reports that viscosity affects measurement accuracy, there is very little experimental data. The viscosity of the liquid changes the damping characteristics of the system, which affects the zero offset; it has a certain degree of influence on the flow meter flow measurement at low flow rates.

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