An optical fiber Fabry-Perot flow measurement technology based on partial bend structure

Area of Science:

• Optical Physics
• Fluid Dynamics
• Sensor Technology

Background:

• Traditional flow measurement often requires invasive probes.
• Developing non-intrusive flow sensing methods is crucial for many applications.
• Optical fiber sensors offer advantages in harsh environments.

Purpose of the Study:

• To present a non-probe optical fiber Fabry-Perot (F-P) flow measurement technology.
• To design and validate a partial bend structure for flow sensing.
• To assess the accuracy and response time of the developed system.

Main Methods:

• Designed a 90° partial bend structure for non-probe flow measurement using pressure difference.
• Utilized fluid simulation to evaluate the pressure difference error of the bend structure.
• Integrated an optical fiber F-P sensor with the bend structure for flow measurement.
• Conducted flow tests across a range of flow rates at ambient temperature.

Main Results:

• Fluid simulation indicated a pressure difference error below 0.05 kPa for the partial bend structure during steady flow.
• The optical fiber F-P sensor demonstrated a pressure test accuracy of 1% full scale.
• Flow tests showed a response time of 1 s for flow rates from 1 m³/h to 6.5 m³/h.
• The overall flow test accuracy of the F-P system was determined to be 4.5%.

Conclusions:

• The optical fiber Fabry-Perot flow test method based on a partial bend structure is effective for fluid flow measurement.
• The non-probe design minimizes flow disturbance and simplifies installation.
• The system exhibits promising accuracy and response times for practical applications.