Research on Dynamic Temperature at Outlet of Centrally Staged Combustor Based on TDLAS Technology

Area of Science:

• Combustion Engineering
• Laser Spectroscopy
• Thermodynamics

Background:

• High-frequency oscillations are a challenge in centrally staged combustors.
• Accurate real-time temperature monitoring is crucial for oscillation suppression.
• Traditional contact methods fail to capture turbulent flow temperature dynamics.

Purpose of the Study:

• To investigate the influence of combustion parameters on temperature uniformity.
• To evaluate the capability of Tunable Diode Laser Absorption Spectroscopy (TDLAS) for non-contact temperature measurement.
• To analyze TDLAS performance at different acquisition frequencies (1 kHz vs. 10 kHz).

Main Methods:

• Utilized non-contact Tunable Diode Laser Absorption Spectroscopy (TDLAS).
• Measured combustor exit temperature at acquisition frequencies of 1 kHz and 10 kHz.
• Varied combustion parameters, focusing on the staging ratio.

Main Results:

• The staging ratio was found to induce irregular oscillations in combustor outlet temperature.
• At 1 kHz, increased staging ratio raised outlet temperature and slowed oscillations.
• At 10 kHz, TDLAS captured finer temperature variations and showed better noise immunity, but limited long-term measurement capability.

Conclusions:

• TDLAS is a viable non-contact method for monitoring combustor temperature oscillations.
• Higher TDLAS acquisition frequencies (10 kHz) provide more detailed dynamic temperature data.
• Trade-offs exist between data detail, noise immunity, and measurement duration based on acquisition frequency.