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Dynamic characteristics of a simple constant-temperature hot-wire anemometer
1Department of Mechanical Engineering, National Taiwan University, Taipei, Taiwan, Republic of China.
The Review of Scientific Instruments
|June 1, 1979
Summary
This study analyzes a constant-temperature hot-wire anemometer, finding its frequency response is limited by the operational amplifier
Area of Science:
- Fluid dynamics and instrumentation engineering.
Background:
- Hot-wire anemometers are crucial for measuring flow velocity.
- Understanding their dynamic response is essential for accurate measurements, especially in transient flows.
Purpose of the Study:
- To analyze and experimentally validate a simple constant-temperature hot-wire anemometer system.
- To investigate the influence of operational amplifier characteristics on the anemometer's frequency response.
Main Methods:
- Theoretical analysis of the anemometer's governing equations, incorporating finite open-loop gain.
- Experimental testing in a shock tube for transient flow conditions.
- Electronic tests to evaluate system parameters.
Main Results:
- Measured natural frequency and damping coefficients align well with theoretical predictions.
- The finite open-loop gain of the operational amplifier significantly limits the frequency response, particularly with short probe cables.
Conclusions:
- The theoretical model accurately predicts the anemometer's dynamic behavior.
- Operational amplifier gain is a critical factor for high-frequency measurements in hot-wire anemometry.
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