具有内流圆管的动特性分析

通过建立圆管在内部流下的振动方程 ,导出了圆管在内部流下固有频率的解析表达式 ,并由此定义了内部流离心力折减影响系数 ,得出了管内流体离心力只有在高流速和管子刚度较小时才对固有频率产生显著影响 ,在低流速和管子刚度较大时可忽略流体离心力对固有频率的影响 ,只考虑流体惯性力的影响。管内流体离心力对低阶固有频率影响较大 ,只有在高流速和管子刚度较小时才会对高阶固有频率产生显著影响。所得结论 ,可供换热器等化工设备计算参考

Dynamic characteristic analysis of circular cylinder with internal axial flow

By establishing the vibration equation of the circular cylinder with internal axial flow, the analysis formula of the circular cylinder is derived, thereby the reduced coefficient of the natural frequency produced by the centrifugal force of the flow in the cylinder is defined. The centrifugal force of the flow in the cylinder has remarkable effect on the natural frequency only when the flow rate is high and the rigidity of the cylinder is small. If the flow rate is low and the rigidity of the cylinder is fairly high, the effect of the centrifugal force on the natural frequency can be neglected, only the effect of the inertial force of the flow should be considered. The centrifugal force of the flow in the cylinder has great effect on the low-order natural frequency, and may have remarkable influence on high-order natural frequency when the flow rate is high and cylinder's rigidity is low. The above conclusions can be used as reference of chemical engineering equipments, such as heat exchangers.