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『MFC mass flowmeter calibration』Related information(clamp on meter|electromagnetic meter|venturi meterrotameter|orifice meter|ultrasonic flow meter|mass flow meter|coriolis mass flow meter|coriolis flow meter|magnetic flow meter|magmeter flow meter|magflow flow meter|mag meter flow meter|electromagnetic flow meter|vortex flow meter|turbine flow meter|thermal mass flow meter|thermal flow meter|rotameter flow meter)
1. Bubble rate of tube furnace
The bubble rate of tube furnace is mainly controlled by gas flow meter. The typical adjustment range of standard laboratory equipment is 10-500 sccm (standard milliliters/minute), and the specific value needs to be accurately set according to the requirements of the reaction process. 1. The core backup section control parameter gas flow rate is the primary parameter for directly controlling the bubble generation rate, which is usually accurately adjusted and displayed through a mass flow controller (MFC) or a rotor flowmeter. Its rate unit is usually sccm (standard milliliters per minute) or slm (standard liters per minute)
2. Influencing factors Gas type: Different gases (such as Ar, N ₂, H ₂) have different viscosity and density, and their actual flow characteristics may vary under the same flow rate setting. Pipeline pressure: The pressure difference between the intake pressure and the pressure inside the furnace tube directly affects the gas flow rate. Temperature: High temperatures in furnace tubes can significantly alter the volume and viscosity of gases, affecting their flow behavior. Liquid medium: If bubbles are generated from a pipe submerged in liquid, the viscosity, surface tension, and liquid level height of the liquid will be key factors. Measurement and observation methods: For bubbles generated from the liquid, high-speed cameras can be used for counting and velocity analysis. For the airflow directly inside the high-temperature pipeline, it is usually measured by a calibrated flow meter rather than directly observing bubbles. Before introducing flammable gases such as hydrogen (H ₂), it is necessary to ensure that the entire gas system is well sealed and un
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2. Why is the measurement value of soap film/float flowmeter inconsistent with the flow measurement value of MFC?
The measurement values of soap film/float flowmeter are inconsistent with those of MFC (mass flow controller), mainly due to the difference in measurement principles and reference conditions between the two. The specific analysis is as follows
1. Differences in measurement principles and reference conditions. Soap film/float flowmeter: belongs to the working condition flowmeter, directly measures the volume flow rate under actual working conditions (working conditions), and the results are significantly affected by temperature and pressure.
. For example, in high-temperature or high-pressure environments, the gas volume expands, and the measured operating flow rate will be higher than the value under standard conditions. MFC (Mass Flow Meter): It belongs to the standard condition flow meter and measures the volume flow rate or mass flow rate under standard conditions (20 ℃, 1atm). It automatically compensates for temperature and pressure changes through sensors and algorithms internally, so the output value is not affected by operating condition fluctuations.2. Conversion relationship between operating conditions and standard condition flow rate. The measured values of the two need to be compared through the following formula: Standard condition flow ra