新型振动流化床的动态特性及试验研究

振动流化床的动态特性是保障良好分选性能的基础，其关键是在模态分析的基础上分析系统的动力响应。采用简化的四自由度多刚体模型从理论上分析了振动流化床的动态特性。利用拉格朗日方程建立该模型的运动微分方程，并对其主体结构进行模态分析，得到了固有频率和模态振型。在模态分析的基础上，分别计算不同相位差的谐波激励下的动力响应，得到了工作频率下相位差与位移响应的关系。通过振动流化床的动态试验验证了动态特性的理论分析结果。试验结果表明试验获得的二阶固有频率为5 Hz，一阶固有频率被二阶固有频率淹没，并证实了位移响应和角位移响应之间存在一定的相位差，相位差是引起摆动的重要原因。为改善振动流化床的动态特性提供了理论依据参考。

Dynamic characteristics and experimental study on a novel structure of vibrating fluidized bed

The basic requirements of perfect separation performance of vibrating fluidized bed are excellent dynamic characteristics.And the basic dynamic characteristics analysis method is dynamic response analysis of the system based on modal analysis.Simplified four DOF multi rigid body model was proposed to deliberate dynamic characteristics of vibrating fluidized bed theoretically.According to the Lagrange equation，the differential equations of simplified model were established.Natural frequency and corresponding vibrating mode of the main structure were obtained by modal analysis.Based on modal analysis，dynamic responses were calculated under the harmonic excitation with different phase differences，and so was the relationship between the phase difference of excitation and the corresponding response of displacement under the condition of working frequency.The validity of theoretical analysis results were confirmed by experimental verification.Experimental results show that the second natural frequency is 5 Hz，the first natural frequency is covered by the second natural frequency，and phase difference，which can be confirmed to be an important reason of swing motion，exists between displacement and angular displacement response.The previous analysis provides an effective method of analysis to improve the dynamic characteristics of vibration fluidized bed.