传统喷雾燃烧采用机械雾化来实现液体燃料的破碎、蒸发以及与空气的混合、燃烧，燃烧电力消耗较大。相比于传统机械喷雾燃烧，金属纤维蒸发式燃烧具有耗电量低、排放低、燃烧效率高等优点。本文通过设计蒸发-燃烧自维持式燃烧器，来研究根部进气结构对蒸发式燃烧器燃烧特性的影响规律，并建立了三维模型，数值模拟了根部旋流进气结构及喉部进气结构对燃烧室温度、污染物及主要产物分布的影响，主要工作如下：

首先对比研究了根部切向旋流进气方式与根部非旋流进气方式对燃烧特性的影响，发现根部切向旋流进气方式燃烧器中反应气体与助燃空气混合时间较长，降低了CO排放，证明了反应气体在高温区域的滞留时间影响CO的生成；旋流进气方式增强了高温烟气向上游的辐射作用，降低了烟气温度，NOx排放较低；从仿真云图中可以看出非旋流进气方式在燃烧器上游温度较低，不利于燃料的蒸发，切向旋流进气方式耗氧速度快，燃烧迅速。当根部进气方式为四孔切向旋流（α=90°）时，偏移角（β）越大，燃烧器上游温度越高，但金属纤维吸油毡附近的温度越低，燃烧器耗氧速度越慢。

其次研究了当根部非切向旋流（α=15°）进气方式（根部进气孔数目为四孔）时，随着偏移角（β）增大，燃烧室内温度升高，污染物排放升高；当β=15°时，燃烧器内CO含量较低且耗氧速度快。当根部进气方式为非切向旋流时（α=15°，β=15°），随着根部进气孔数目的增多，燃烧室温度降低，火焰面位置向出口移动，但当进气孔数目为双孔时，金属纤维吸油毡附近温度低于400℃，燃烧室温度较低，实验中火焰较小，污染物排放较高；从仿真结果来看双孔旋流在燃烧器下游温度较低，O₂含量高，H₂O含量低。

最后仿真模拟了喉部进气结构参数对燃烧特性的影响。发现喉部进气孔直径越大，燃烧器温度越低，耗氧速度越慢；当喉部进气孔数目为六孔时，NOx排放最低，燃烧器内CO含量最高；喉部烟气出口直径为64mm时（与燃烧室内筒直径之比为1:0.74），污染物排放最低；喉部进气孔主要影响燃烧器下游的污染物分布，对燃烧器上游影响较小。

Traditional spray combustion uses mechanical atomization to achieve the breaking of liquid fuel, evaporation and mixing with air, combustion, combustion power consumption is large. Compared with traditional mechanical spray combustion, metal fiber evaporative combustion has the advantages of low power consumption, low emissions, and high combustion efficiency. In this paper, we design the evaporation-combustion self-sustaining combustor to study the influence law of root inlet structure on the combustion characteristics of evaporative combustor, and establish a three-dimensional model to numerically simulate the influence of root cyclone inlet structure and throat inlet structure on the combustion chamber temperature, pollutants and main products distribution, the main work is as follows:

Firstly, the effects of root tangential cyclonic intake and root non-cyclonic intake on combustion characteristics were comparatively studied, and it was found that the longer mixing time between the reaction gas and combustion air in the root tangential cyclonic intake combustor reduced CO emissions, proving that the retention time of the reaction gas in the high temperature region influenced the generation of CO; the cyclonic intake enhanced the radiation of high temperature flue gas upstream and reduced the flue gas temperature, NOx emission is lower; from the simulation cloud diagram, we can see that the non-cyclonic inlet method has lower temperature upstream of the burner, which is not conducive to fuel evaporation, and the tangential cyclonic inlet method has fast oxygen consumption and rapid combustion. When the root intake method is four-hole tangential cyclonic flow (α=90°), the larger the offset angle (β), the higher the upstream temperature of the burner, but the lower the temperature near the metal fiber absorbent felt, the slower the oxygen consumption rate of the burner.

Next, when the root non-tangential cyclonic flow (α=15°) intake method (the number of root intake holes is four) is studied, the temperature inside the combustion chamber increases and the pollutant emission increases as the offset angle (β) increases; when β=15°, the CO content inside the combustor is lower and the oxygen consumption rate is faster. When the root inlet is non-tangential cyclonic flow (α=15°, β=15°), with the increase of the number of root inlet holes, the combustion chamber temperature decreases and the flame surface position moves toward the outlet, but when the number of inlet holes is double holes, the temperature near the metal fiber absorbent felt is lower than 400°C, the combustion chamber temperature is lower, the flame is smaller in the experiment, and the pollutant emission is higher; from the simulation results the double-hole cyclonic flow in the combustor The downstream temperature is lower, the O₂ content is high and the H₂O content is low.

Finally, the effect of the throat intake structure parameters on the combustion characteristics was simulated. It is found that the larger the throat inlet diameter is, the lower the burner temperature is and the slower the oxygen consumption rate is; when the number of throat inlet holes is six, the NOx emission is the lowest and the CO content in the burner is the highest; when the throat flue gas outlet diameter is 64 mm (the ratio with the inner cylinder diameter of the combustion chamber is 1:0.74), the pollutant emission is the lowest; the throat inlet holes mainly affect the pollutant distribution in the downstream of the burner and have less influence on the upstream of the burner The impact on the upstream of the burner is smaller.