Laser absorption spectroscopy for combustion diagnosis in reactive flows: A review

Abstract

Laser absorption spectroscopy (LAS) has been rapidly developed and widely applied to combustion diagnosis in recent decades. As a costeffective tool for measuring multiple combustion parameters, LAS provides unique properties in terms of accuracy and sensitivity for understanding the reactions and kinetics in reactive flows. Line-ofsight and tomographic LAS techniques have stimulated numerous applications and been proved to be robust for in situ combustion diagnosis in uniform and non-uniform combustion fields, respectively. This review highlights the breakthroughs in the evolution of LAS techniques from the viewpoints of key principles, sensors and instrumentations developed for combustion diagnosis, with particular emphasis on a series of spatially-resolved LAS techniques with their recent applications on obtaining high-fidelity measurement results with minimal intrusion to the practical combustors. Along the way, we note some challenges and requirements for further development of the LAS-based combustion diagnosis.

Laser Absorption Sensing Systems: Challenges, Modeling, and Design Optimization

“…Goldenstein et al provided a thorough review of the underlying fundamentals, design, and use of infrared LAS sensors for combustion gases and highlighted recent findings and some of the remaining measurement opportunities, challenges, and needs [12]. Liu et al summarized the key principles and recent advances of line-of-sight (LOS) LAS techniques and then focused on spatially resolved gas sensing with LAS tomography [13].…”

Toward Customized Spatial Resolution in TDLAS Tomography

“…ASER spectroscopic techniques have been extensively applied to combustion diagnostics, enabling better understanding of the turbulence, heat transfer and chemical reactions in the flow fields [1]. Among these techniques, tunable diode laser absorption spectroscopy (TDLAS) provides high speed and high sensitivity using wavelength-tunable laser diodes [2][3][4]. In the past, line-of-sight TDLAS has been used to retrieve quantitatively the path-averaged temperature, species concentrations, pressure and velocity in reactive flows.…”

Time-resolved continuous-filtering Vernier spectroscopy of H2O and OH radical in a flame

“…Among these techniques [5][6][7][8] laser absorption spectroscopy is one of the most quantitative methods for selective sensing of gas temperature and composition [9,10]. However, the detection bandwidth of absorption techniques based on continuous wave lasers such as wavelength modulation spectroscopy (WMS) [11,12] and cavity ring-down spectroscopy [13][14][15][16] is usually limited to 1-2 cm −1 [17,18]. Much larger detection bandwidth is provided by techniques based on broadband sources such as optical frequency combs [19][20][21], supercontinuum sources [22,23] and Fourier-domain mode-locked lasers [24].…”