Gas viscosity measurement with diamagnetic-levitation viscometer based on electromagnetically spinning system
Y Shimokawa1, Y Matsuura1, T Hirano1
1Institute of Industrial Science, The University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan.
The Review of Scientific Instruments
|January 3, 2017
Summary
This study introduces a novel friction-free viscosity measurement system for gases. The innovative method accurately measures gas viscosity, even at very low levels (μPa·s), with high sensitivity.
Area of Science:
- Physics
- Materials Science
Background:
- Traditional viscometry methods often suffer from mechanical friction, limiting accuracy.
- Measuring the viscosity of gases, especially at low levels, presents significant challenges.
Purpose of the Study:
- To develop a novel, friction-free system for accurate gas viscosity measurement.
- To demonstrate the system's sensitivity and accuracy across various gases and temperatures.
Main Methods:
- A graphite-disk probe with an aluminum disk was levitated using diamagnetic effects from a NdFeB magnet.
- Electromagnetically induced torque was used to rotate the probe, enabling friction-free operation.
- Gas viscosity was measured by analyzing the probe's rotational response.
Main Results:
- The system successfully measured the viscosity of eight different gases.
- Accurate viscosity measurements were obtained across a temperature range of 278 K to 318 K.
- The method demonstrated the capability to measure fluid viscosity in the order of μPa·s.
Conclusions:
- The developed friction-free system offers a highly accurate and sensitive method for gas viscosity measurement.
- This technique overcomes limitations of traditional viscometers, enabling precise measurements at low viscosity levels.
- The system shows promise for various applications requiring precise fluid property analysis.
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