Research On Load Sharing And Dynamic Characteristics Of Marine Star Gear Reducer

Currently, high-speed, heavy duty, large flexibility and high precision have become the mainstream of the development of marine gearbox; therefore its dynamic properties for further research are particularly important. The star gear reducer is an important device in marine power transmission. To establish an advanced theory of calculation and analysis, and set out its dynamic characteristics, have great significance in improving the carrying capacity and reducing vibration and noise.First of all, the basic principle of static load sharing has been presented in this paper. On the basis of the analysis, the physical model of load sharing was established to research the reason of uneven load production. The load sharing coefficient of the star gear train was calculated, and the sensitivity of the load sharing coefficient on manufacturing errors, installation error and tooth thickness deviation was analyzed.Then a full-tooth finite element model of gear mesh was established, using contact FEM algorithm to calculate dynamic excitation in the work condition, taking into account the influence of stiffness excitation and error excitation, the dynamic force of the gear meshing and the dynamic forces at the bearings were calculated, which provided preconditions for the dynamic response analysis of gear box.The 3D solid models of the star gear train and the gearbox were established in this paper. A coupled model of the gear train was created by using the pool node connection. The modal analysis for the single gearbox and the coupled model were completed, and the natural frequency and modal shape were calculated and compared.Finally, on the basis of the modal analysis of the coupled modal, the dynamic response of the gearbox was analyzed, taking into account the influence of stiffness excitation and error excitation, and then the displacement, speed and acceleration of the gearbox were obtained. The noise value in the key point was obtained by carrying 1/3 octave processing to normal vibration acceleration curve in the frequency range, and then predicted the noise value of the gearbox.These researches provided a useful theoretical basis and an effective means on the highly reliable design of gear drives, and it has important practical significance in reducing vibration and noise on the marine gear reducer.