氢气乙醇混合物层流燃烧速度及火焰不稳定性研究
摘要:氢气是一种高效的添加剂，可改善乙醇燃料的燃烧特性，为更好地应用于燃烧装置，有必要研究其层流燃烧特性。在初始压力为0.1及0.4 MPa，初始温度为400 K，等效比范围为0.7～1.4，氢气比例为20%、50%和80%下进行实验，采用定压法(constant pressure method，CPM)得到层流燃烧速度(laminar burning velocity，LBV)。对火焰发展不同阶段的火焰形貌进行研究，当火焰表面的大裂纹分裂出现小裂纹，并导致新细胞再生时，火焰变得不稳定；还研究流体动力学效应和热扩散效应对火焰固有不稳定性的影响。结果表明：LBV随着氢气比例的增加而增加，在富氢状态下其提升效果更加显著；流体动力不稳定性随着压力的增加而增加，热扩散不稳定性对压力变化不敏感；此外，增加氢气比例或初始压力将使火焰更早变得不稳定。
Abstract：Hydrogen is an efficient additive to improve the combustion characteristics of ethanol fuels. For better application in combustion devices, it is necessary to study its laminar combustion characteristics. The experiments are conducted at an initial pressure of 0.1, 0.4 MPa, an initial temperature of 400 K, an equivalent ratio in the range of 0.7~1.4, and the H2 ratios of 20%, 50% and 80%. The laminar burning velocity (LBV) is obtained using the constant pressure method (CPM). The flame morphology is studied at different stages of flame development, and the flame becomes unstable when the large cracks on the flame surface are split into small cracks and led to the regeneration of new cells. The effects of hydrodynamics and thermal diffusion on the inherent instability of the flame are also investigated. The results show that the LBV increases with the increase of hydrogen proportion, and the enhancement effect is more significant in the hydrogen-rich state. The hydrodynamic instability increases with the increase of pressure, and the thermal diffusion instability is insensitive to the pressure change. In addition, increasing the hydrogen ratio or initial pressure can cause the flame to suffer from instability earlier.
标题：氢气乙醇混合物层流燃烧速度及火焰不稳定性研究
title:Study on Laminar Burning Velocity and Flame Instability of Hydrogen-Ethanol Mixture
作者：张璇,王筱蓉,张嘉玮,张衍
authors:ZHANG Xuan,WANG Xiaorong,ZHANG Jiawei,ZHANG Yan
关键词：氢气－乙醇,定容燃烧弹,层流燃烧速度(LBV),热扩散不稳定,
keywords:hydrogen-ethanol,constant volume combustion bomb,laminar burning velocity (LBV),thermal diffusion instability,
发表日期：2023-05-12
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