基于压力波动的煤粉工业锅炉炉膛振动试验研究

Experimental study on furnace vibration of industrial pulverized coalboiler based on pressure fluctuation

若煤粉工业锅炉的炉膛振动过大则易影响锅炉的安全运行,对基于压力波动的煤粉工业锅炉炉膛振动进行试验研究,可调整其燃烧参数并为锅炉的安全运行提供基础支撑。为了研究煤粉工业锅炉振动产生的原因,进而探究降低锅炉振动的方法,在1台40 t/h蒸汽煤粉工业锅炉上开展试验,研究不同因素对锅炉压力波动和频率的影响,并分析压力波动和自身固有振动与炉墙振动的关系。试验结果表明:煤粉工业锅炉的炉膛各个位置受到的压力基本相同;煤粉工业锅炉中存在频率约为5 Hz的特征压力波动,锅炉的负荷越大,特征压力波动越大、频率越高;二次风越大,特征压力波动越小。结合理论分析认为煤粉工业锅炉的特征压力波动是由燃烧器和预燃室里的火焰脉动燃烧所产生,因而应增加炉墙的刚性以及避免炉墙的固有频率与炉膛压力波动的主要频率叠加,从而有效降低炉墙的振动。

If the furnace vibration of pulverized coal industrial boiler is too large,it is easy to affect the safe operation of the boiler.The experimental study on the furnace vibration of pulverized coal industrial boiler based on pressure fluctuation can adjust its combustion parameters and provide basic support for the safe operation of the boiler.In order to study the causes of vibration of pulverized coal industrial boilers and explore ways to reduce the boiler vibration,an experiment was carried out on a 40 t/h steam pulverized coal industrial boiler to study the influence of different factors on the boiler pressure fluctuation and frequency,the relation of pressure fluctuation and Inherent vibration and furnace wall vibration were analyzed.The test results show that the pressure at each position of the furnace of the pulverized coal industrial boiler is basically the same;the characteristic pressure fluctuation with a frequency of about 5 Hz exists in the pulverized coal industrial boiler.The greater the boiler load,the greater the characteristic pressure fluctuation and the higher the frequency.The larger the secondary wind,the smaller the characteristic pressure fluctuation.According to the theoretical analysis,the characteristic pressure fluctuation of pulverized coal industrial boiler is caused by the pulsation combustion in the burner and precombustion chamber,so the rigidity of the furnace wall should be increased and the natural frequency of the furnace wall should be avoided to superimpose with the main frequency of the furnace pressure fluctuation,so as to effectively reduce the vibration of the furnace wall.