【摘要】 通过对谐波小波频谱边缘突变点应用Hanning窗进行光滑处理,改善了谐波小波的时域衰减特性,并给出实现算法。通过对离心风机旋转失速的试验研究,应用改进的谐波小波时频等高线图对不同测量部位的动态压力信号进行时频分析,得出在不同导流器开度下离心风机不同的特征和弱失速区域的能量间歇现象,风机最高效率线与失速边界线比较接近,并且在导流器小开度下会出现交叉,说明弱失速区域应引起运行、维修人员足够重视。图10参8更多还原

【Abstract】 The frequency spectrum discontinuity point of harmonic wavelet is smoothed by putting Hanning windows and the decay rate of wavelet in time domain is improved. The realization algorithm is also given. The experimental investigation is carried through on centrifugasl fan in laboratory and the measured dynamic pressures in different point are analyzed by timefrequency contour map of reformed harmonic wavelet. The different characteristic of stall in different inlet guide vane(IGV) angle and the energy intermission in weak stall region is gained. The highest efficiency curve is close to the stall limit curve and intersect in small IGV angle. Figs 10 and refs 8.更多还原