Why is a Cryogenic Flow Meter Necessary for Liquid Nitrogen Mass Flow Measurement?
The field of science that focuses on studying the physical properties of substances under low temperature conditions, including products obtained at low temperatures and their measurement techniques, is known as low temperature physics. Cryogenic liquids, defined as substances with temperatures below -238°F, play a crucial role in this field. Industrial cryogenic flow meters are used to measure the flow rate of various cryogenic liquids such as liquid nitrogen (N2), refrigerated liquids, coolants, neon (Ne), liquid argon, CO2, methane, hydrogen, carbon monoxide, and liquid helium. These flow meters find extensive applications in the dairy industry, food storage, cooling systems, chilling and freezing applications, mechanical cryocoolers, thermally insulated containers, and medical applications.
Challenges in Measuring Cryogenic Liquids and Available Flow Meter Devices
Measuring the flow rate of cryogenic liquids, particularly liquid nitrogen, is challenging due to their extreme cold temperatures. Only a few flow meter devices are capable of accurately detecting cryogenic liquefied nitrogen. For instance, a magnetic flow meter can detect temperatures as low as -25°C, while an oval gear flow meter can handle liquid temperatures as low as -40°C. Digital variable area rotameters can detect temperatures as low as minus 34°F. However, Silver Automation Instruments offers a Coriolis flow meter that can detect temperatures as low as -200 °C (73K) which can be used as
liquid nitrogen mass flow measurement.
Coriolis Mass Flowmeters for Liquid Nitrogen Mass Flow Measurement
Coriolis mass flowmeters are widely used for liquid nitrogen mass flow measurement. These meters work by utilizing the Coriolis force principle, which is directly proportional to the mass flow when the fluid flows through the vibrating pipe. Coriolis mass flow meters are particularly suitable for measuring the flow of high-viscosity non-Newtonian fluids, such as latex, paint and coating vitamin slurry, paper pulp, water, heavy oil, polymer, bitumen, and vapors. They are also effective for measuring high-temperature and cryogenic liquid flows. Coriolis flow transmitters can handle low temperature fluids like cryogenic liquid nitrogen, argon, and helium.
Technical Specifications for Selecting a Cryogenic Flow Meter for Liquid Nitrogen Measurement
When selecting a cryogenic flow meter for liquid nitrogen, certain technical specifications should be considered. The minimum temperature for fluid temperature is -200 °C (-328 °F). The cryogenic flow meters come in different sensor sizes, ranging from 1/8" to 8". It has a pressure rating of up to 200 bars and a precision of ±0.2%FS. The wet parts material for the cryogenic flow sensor is made of stainless steel 316L. The power supply can be either external 24VDC or 220V AC, and the output signal can be 4-20mA or pulse 0-1000HZ with RS485 communication. The cryogenic flow meter has a protection level of IP65 and be explosion-proof with an intrinsically safe ExiallCT5 rating. It also has a digital display to show the cryogenic liquid mass flow rate, totalized flow, and liquid temperature. Optionally, it can be equipped with insulating housings and a heating jacket to prevent freezing of the sensor.
Conclusion: Importance of Cryogenic Flow Meters in Accurate Liquid Nitrogen Flow Measurement
In conclusion, a cryogenic flow meter is essential for accurately measuring the flow rate of cryogenic liquids like liquid nitrogen.
Coriolis mass flow meters are highly suitable for this purpose, offering advanced and accurate measurement capabilities. When selecting a cryogenic flow meter, it is important to consider the technical specifications to ensure optimal performance in measuring liquid nitrogen mass flow rates.