High-temperature flow field's electron number density measurement by two-wavelength moiré tomography

Area of Science:

• Plasma Physics
• Optical Diagnostics
• Fluid Dynamics

Background:

• High-temperature complex flow fields, such as plasmas, are crucial in various industrial and research applications.
• Accurate measurement of electron number density distribution is essential for understanding and controlling these phenomena.
• Existing indirect methods for electron density measurement can suffer from imprecision.

Purpose of the Study:

• To propose and demonstrate a direct method for measuring electron number density distribution in high-temperature complex flow fields.
• To establish and validate an experimental system for two-wavelength moiré tomography.
• To provide a reliable optical measurement technique for high-density gradient flow fields.

Main Methods:

• Development of a two-wavelength moiré tomography experimental system.
• Utilization of two probe wavelengths (532 nm and 808 nm) for plasma measurement.
• Application of the technique to argon arc plasma as an experimental case.

Main Results:

• Successful direct measurement of electron number density distribution in argon arc plasma.
• Demonstration of the capability of two-wavelength moiré tomography to resolve complex flow fields.
• Validation of the method's accuracy compared to indirect techniques.

Conclusions:

• Two-wavelength moiré tomography offers a direct and precise method for electron number density measurement.
• The developed technique overcomes the imprecision associated with indirect measurement approaches.
• This method serves as a valuable reference for optical measurement and diagnosis of high-temperature, high-density gradient flow fields.