Tomographic imaging using multi-simultaneous measurements (TIMes) for flame emission reconstructions.

Area of Science:

• Combustion science
• Optical diagnostics
• Fluid dynamics

Background:

• Accurate flame visualization is crucial for understanding combustion processes.
• Existing methods may struggle to resolve complex flow structures and mixing zones.

Purpose of the Study:

• To present and validate the tomographic imaging using multi-simultaneous measurements (TIMes) method for flame emission reconstruction.
• To visualize and analyze three-dimensional flame structures and mixing dynamics.

Main Methods:

• Utilized natural CH* chemiluminescence and seeded alkali metal salt luminescence.
• Employed an array of 29 CCD cameras with bandpass filters for multi-spectral data acquisition.
• Reconstructed instantaneous and time-averaged 3D fields for different Reynolds numbers.

Main Results:

• Successfully reconstructed flame fronts by identifying the interface between burnt and cold gas regions.
• Demonstrated increased mixing in downstream directions for higher Reynolds numbers due to enhanced turbulence.
• Distinguished combustion zones from different streams and their overlap regions within the entire volume.

Conclusions:

• The TIMes method provides detailed 3D insights into flame structure and mixing.
• This technique is effective for analyzing complex turbulent flames and identifying distinct combustion zones.