强声激励对煤粉燃烧的强化作用的数值研究  

Numerical study on the enhanced effect of strong acoustic excitation on pulverized coal combustion

作　　者：赵文嘉 姜根山[2,3] 刘月超 姜羽[2] ZHAO Wenjia;JIANG Genshan;LIU Yuechao;JIANG Yu(North China Electric Power University(Baoding),Baoding 071003,Hebei,China;North China Electric Power University,Beijing 102206,China;Hebei Key Laboratory of Physics and Energy Technology,Baoding 071003,Hebei,China)

机构地区：[1]华北电力大学(保定),河北保定071003 [2]华北电力大学,北京102206 [3]河北省物理学与能源技术重点实验室,河北保定071003

出　　处：《声学技术》2024年第5期613-620,共8页Technical Acoustics

基　　金：国家自然科学基金资助项目(12074118,11474091,12274122)。

摘　　要：声波激励在火力发电厂等的工程应用中有良好的前景,可以有效提高煤粉燃烧效率。文章采用声波激励强化煤粉燃烧模型,并通过建立二维煤粉燃烧数值计算模型,在该模型下求解Arrhenius动力反应速率,反应模型采用有限速率/涡耗散模型,分析燃烧区域温度场在不同进风速度与进煤速度配比(U_(0)/U_(1))、不同声压级(135~165 dB)和不同声波频率(50~5000 Hz)下的燃烧区域温度场的变化规律。结果表明:该方法可以有效地表征声波对燃烧的强化作用,当进风速度与进煤速度之比U_(0)/U_(1)为1.39,煤粉受到声压级为165 dB、声波频率为50 Hz的低频高强声作用时,声波对流场的扰动效果最好,燃烧区域的温度最高,强化燃烧效果最佳。Acoustic excitation has a good application prospect for thermal power plants,which can effectively improve the combustion efficiency of pulverized coal.In this paper,the model of pulverized coal combustion enhanced by acoustic excitation is adopted.The Arrhenius dynamic reaction rate is solved by establishing a two-dimensional numerical calculation model of pulverized coal combustion.The reaction model adopts the finite rate/vortex dissipation model.The temperature field in combustion area is analyzed under different ratios of air inlet speed to coal powder inlet speed(U_(0)/U_(1)),different sound pressure levels(135-165 dB)and different acoustic frequencies(50-5000 Hz).Numerical results show that,this method can effectively characterize the strengthening effect of sound waves on combustion.For U_(0)/U_(1)=1.39,when the coal powder is affected by the 50 Hz high-intensity sound pressure level of 165 dB,the acoustic wave has the best disturbance effect on the flow field,the temperature in the combustion area is the highest,and the enhanced combustion effect is the best.

关 键 词：声波 煤粉 燃烧 温度 

分 类 号：O422[理学—声学] O429[理学—物理]