中文摘要：

应用计算流体动力学（CFD）技术对Rijke管内的声学特性进行了研究．采用内外流场耦合建模方法研究Rijke管内流场，得到了相应的管口声压和声泄漏值．提出热源周围空气非定常热流量与声压、脉动速度之间关系的假设．依靠自身参量如声压、速度和温度的波动来激发Rijke管振荡，模拟了Rijke管的声学特性，得到管口声压分布云图，分析了模拟中出现的物理现象，解释了Rijke管自激励振荡的机理．进行了Rijke管管口截面收缩的模拟实验，得到了管口收缩能使噪声降低的结论．

英文摘要：

A computational fluid dynamics （CFD） technique was utilized to study the pulsation mechanism inside a Rijke tube. The simulation of flow field, which coupled the inner space of Rijke tube with its outer space, was carried out to replace the traditional way by means of internal flow field numerical investigations. A hypothesis of the relationships among wosteady heat of air around heat source, oscillation pressure and oscillation velocity was presented. To reflect the essence of Rijke tube, simulation of self-excited oscillation was obtained by means of pulsation of pressure, velocity and temperature. Cloud charts of pressure distribution of nozzle and leakage value of sound pressure were drawn. The physical phenomenon of self-excited Rijke tube was analyzed. Moreover, the self-excited oscillation mechanisms of Rijke tube were explained. Based on this method, comparative research on the acoustic characteristics of Rijke pipe with nozzles of different sizes was performed. Results show that noise can be lowered by redusing the nozzle size.