Computer simulation and investigation vibration parameters of a centrifugal submersible pump

The dynamic characteristics of one of the centrifugal pump critical parts such as the rotor shaft are studied in the article whilst the highest level NASTRAN CAD PATRAN module was used to carry out the dynamic analysis. During the analysis a computational mechanical scheme has been compiled as well as force factors generating rotor vibrations have been determined. The axial, radial and hydrodynamic forces affecting the impeller and pump shaft have been calculated according to the analytical formula. Under the given boundary conditions in the FE model and the chosen method for determining the natural vibrations, a numerical solution of the equations of free and forced vibrations has been found using the algorithms of the NASTRAN program. The natural vibrations of the rotor have been determined using the Lanczos method. The dynamic stability of the shaft, the stress-strain state of the shaft and its displacement under static loads, the frequency and shape of the natural vibrations of the rotor necessary for the calculations have been determined. The amplitude-frequency characteristics of the system have been determined and analyzed for affection by external forces at the reverse and blade frequencies. Using the amplitude parameters of the forced oscillations, the dynamic gain of the rotor has been determined. Based on the amplitude-frequency parameters, the option of the number of blades for the working centrifugal impeller of the pump has been justified. The technique of computer simulation and determination of the vibroactivity parameters of a submersible centrifugal pump rotor shaft is given in the article.