气流式雾化火焰声压分布特性试验研究

研究气流式雾化火焰声压分布特性,建立火焰长度与声压分布之间的关系,分析不同火焰长度对火焰噪声辐射特性的影响。结果表明:火焰噪声声压场可根据火焰长度L划分为三个区域:近场区、衰减区和远场区;近场区声压值最大,为气流式雾化火焰噪声的产生区域,燃烧噪声为主要噪声源;衰减区为噪声的最佳采样区域,可测得噪声的总声压值;远场区声压变化幅度很小,可近似等于远场声压;随着火焰长度的增加,火焰噪声的指向性越明显,辐射强度越大。

Experimental Study on Sound Pressure Distribution of Air-Blast Atomization Flame

Sound pressure distribution of air-blast atomization flame was studied. Relationship between flame length and sound pressure distribution was established and influence of different flame length on the radiation characteristics of flame noise was analyzed. Results show that flame noise sound pressure field can be divided into three regions according to the flame length L: near-field zone, attenuation zone and far-field zone. Near-field zone is the generation area of air-blast atomization flame noise, where the value of sound pressure is the largest and combustion noise is the main noise source. Attenuation zone can be used as the best noise sampling area, in which the total sound pressure can be measured. Far-field zone changes in the value of sound pressure is very small and the value can be approximately equal to the far-field sound pressure. With the increase in flame length, the direction of flame noise is more obvious and the radiation intensity is greater.