论文标题
使用单个可调二极管激光器的燃烧气体中温度,水和二氧化碳浓度的层析成像的计算研究
A computational study for tomographic imaging of temperature, water and carbon dioxide concentration in combustion gases using a single tunable diode laser
论文作者
论文摘要
当今需要优化燃烧过程和催化效率以最大程度地减少污染物,这可以通过内部分析燃烧过程中的温度和燃烧产物分布来进行。本文通过扫描单个窄带激光器,讨论了温度和浓度$ _2 $和h $ _2 $ o的2-D断层成像的可行性。在2000 nm的波长范围内讨论了H $ _2 $ O的光谱线的选择。选择此区域是因为H $ _2 $ O和CO $ _2 $频谱线具有足够的强度水平。发现了一对波数(5005.53和5003.3 cm $^{ - 1} $)是温度中最佳的,h $ _2 $ o浓度分布和5004.36 cm $^{ - 1} $被选择用于CO $ _2 $。为了确定不同重建算法的功效,使用四种重建技术尝试了双峰温度分布的幻象和同心温度分布的幻象。对于使用过滤的Landweber和Tikhonov正则化方法的相同类型的幻像,对于温度的分配以及h $ _2 $ o和co $ _2 $的浓度实现了令人印象深刻的重建,用于5005.53和5003.3 cm $^{ - 1} $。最初,使用扇形和离散的不规则束阵列尝试了成像,分别具有100和31梁。后来的横梁并不少,而是显示出非常有希望的结果。
There is a present-day need of optimization of the combustion processes and catalytic efficiency for minimization of emission of pollutants, which can be possible by analyzing the temperature and combustion products distribution in the combustion processes internally. This paper discusses the feasibility of simultaneous 2-D tomographic imaging of temperature and concentrations of CO$_2$ and H$_2$O by scanning a single narrowband laser. The choice of spectroscopic lines of H$_2$O for two-tone temperature measurement is discussed around the wavelength range of 2000 nm. This region is selected as both H$_2$O and CO$_2$ spectral lines have sufficient intensity levels. The pair of wavenumbers (5005.53 and 5003.3 cm$^{-1}$) is found the best of all for temperature and H$_2$O concentration distribution and 5004.36 cm$^{-1}$ is chosen for CO$_2$. To establish the efficacy of different reconstruction algorithms, the phantoms of bimodal and concentric temperature distribution with uniform concentration were tried with four reconstruction techniques. Impressive reconstructions were achieved for distribution of temperature and concentrations of H$_2$O and CO$_2$ for same types of phantoms using Filtered Landweber and Tikhonov regularization methods for 5005.53 and 5003.3 cm$^{-1}$. Initially the imaging was tried using both fanbeam and discrete irregular beam array with 100 and 31 beams respectively. Instead of less number of beams, the later one also shows very promising result.