作为生物柴油连续生产装置的核心单元，扁平形超声反应器的停留时间分布直接反映反应器内的流型、返混程度和反应效果，对反应器设计、操作和控制具有重要意义．文中采用 pHB-3 型 pH 仪，以纯净水作流体、KOH 溶液作示踪剂，采用脉冲法实时测定了扁平形多频超声辐射反应器的出口 KOH 应答信号，得到了反应器内流体的停留时间分布曲线，研究了超声功率和流体流量对反应器内流体流动形态及非理想性的影响． 同时，用多釜串联模型对实验数据进行相关模拟，得到以下结论:在超声功率为 200 W，流量分别为 20、30L/h 时，理论串联釜数目分别为 6. 06、6. 76，且流量较大时模拟效果较理想，此时槽内流体更趋于平推流．

Flatted ultrasonic reactor is the core component of the continuous biodiesel production equipment． As a reflection of the flow pattern，the back-mixing degree and the reaction effect，the residence time distribution (RTD) is significant to the design，manipulation and control of flatted ultrasonic reactors． In this paper，the RTD curves were obtained through measuring the outlet KOH concentration of the flatted multi-frequency ultrasonic reac-tor with a pHB-3 type pH tester in real time，with KOH solution as the tracer in the pulse method and with purified water as the main fluid． Then，the contributions of ultrasonic power and fluid flow to the flow condition and non-ideality of the fluid in the reactor were investigated，and a fitting of the experimental data was performed by using a continuous-flow stirred tank reactor (CSTR) model． The results show that，under the action of 200W ultrasonic，the theoretical number of series kettles is respectively 6. 06 and 6. 76 when the flow rate is respectively 20 and 30L/h; and that，at a high flow rate，the simulation effect becomes better and the flow pattern most likely tends to plug flow．