Vibration Frequency Of System Research Articles

Calculation of Nature Frequency for Ship’s Tail Shaft Flexural Vibration Based on Genetic Algorithm

Analysis of the nature frequency of flexural vibration is vital to be able to provide effective shock absorption for a ship’s tail shaft. The paper built mathematic model of ship’s tail shaft flexural vibration by transfer matrix method, and put forward an effective method for calculating the natural frequency of vibration system: a genetic algorithm (GA). Through example calculation compared with Prohl method under conditions bearing isotropic supporting, the result showed that the method can meet the requirements of engineering calculation, and overcome the disadvantage that initial value of calculation is difficult to be obtained with other methods. Then the method has advantage especially when the degrees of frequency equation increase.

Study on Dynamical Characteristics of Catenary Transformer in Gear Honing

Ultrasonic vibration can reduce honing forces efficiently. As the honing wheel can be washed by ultrasonic cavitations of cooling liquid, its jams are decreased and the higher honing efficiency has obtained. Therefore, the combination of ultrasonic machining and gear honing is a method for gear fine machining with its wide application future. However, the gears with big diameter and thickness machined by ultrasonic honing are special loads, which influence the machining frequency of vibration system heavily. Hence, the horn and gear must be considered at the same time while designing the vibration system. In this paper, the frequency equations are derived according to stress match, wherein, the gear is considered as a thin disc and catenary horn is adopted. Then the influences of vibration of transformer that consists of horn and gear are investigated with the variety of the horn length and the machining frequency. The theoretical analysis shows that the resonance frequency of the horn and detune frequency of transformer have the different value. The results are proved by FEM, too.

Dynamical characteristics of exponential transformer in gear honing

Ultrasonic vibration can reduce honing forces effi-ciently and ultrasonic cavitation and machining liquid can real-ize real-time dynamic washing, which decrease the jam of hon-ing wheel and increase the honing efficient, so the composition of ultrasonic machining and gear honing is a fine machining of gears with good application future. The gears with big diameter, thickness, which are machined by ultrasonic honing, are special loads which influence the machining frequency of vibration system heavily, hence the horn and gear must be considered at same time while the vibration system is designed. The fre-quency equations are derived according to stress match, consid-ering gear as a thin bar and adopting exponential horn. Then the influences of vibration of transformer which consists of horn and gear are explored, which come from the length of horn and the machining frequency. It has been discovered that the reso-nance frequency of the horn is the detune one of transformer and the resonance frequency is not same as one of horn, which provide theoretical rules for transformer design.