用压力波动的小波高频分量检测燃烧不稳定性

针对燃烧不稳定性检测问题,提出利用燃烧压力波动的小波高频分量检测燃烧不稳定性的方法.为验证该方法,采用微压传感器测量了层燃炉稳定燃烧和不稳定燃烧工况下的压力波动,运用Daubechies一阶小波提取了它们的高频分量进行对比.结果表明,压力波动的小波低频分量表征了炉内压力水平的整体变化,而高频分量则与湍流和燃烧噪音强度变化一致.燃烧稳定时,小波高频分量幅值基本恒定;而燃烧不稳定时,压力波动的小波高频分量的幅值出现较大波动.

The Combustion Instability Detection Using the Wavelet Detail of Pressure Fluctuations

A combustion instability detection method that uses the wavelet detail of combustion pressure fluctuations was put forward.To confirm the method,combustion pressure fluctuations in a stoker boiler are recorded at stable and unstable combustion with a sensitive pressure transducer.Daubechies 1-order wavelet is chosen to obtain their wavelet details for comparison.The result shows that the wavelet approximation indicates the overall pressure change in the furnace,and the wavelet detail magnitude is consistent with the intensity of turbulence and combustion noise.The magnitude of the wavelet detail is nearly constant when the combustion is stable,while the magnitude of the wavelet detail will fluctuate much when the combustion is unstable.