The figure shows the rotor model of a typical integral 5-stage centrifugal compressor. As shown in figure a), TST, WST, ST12, ST3 and ST45 are respectively drive shaft, big gear shaft, first / second stage gear shaft, third stage gear shaft and fourth / fifth stage gear shaft. Each impeller is located at the shaft end of first / second stage gear shaft, third stage gear shaft and fourth / fifth stage gear shaft. For the convenience of analysis, a simulation disk with the same mass and moment of inertia is used instead (see Fig. a)).
The distribution of the axis position of each gear rotor is shown in Fig. b). It can be seen from Fig. B that the rotors of each stage are non-uniform in circumference with the big gear shaft as the center; The axes of ST12 and ST3 are on the x-axis, the axis of TST is on the y-axis, and the angle between the axis of ST45 and the axis of WST and the y-axis is 0 θ。 The center distance, transmission ratio and included angle between gears of all stages θ Such parameters need to be designed comprehensively according to the performance and installation space of impellers at all levels.