Optimum design of journal bearings dimensions for rotating machines

Abstract EN

The values of Manyparameterswhich involve in the design of fluid film journal bearings mainly depend on the bearing applied loadwhen using theconventional design method to design the journal bearings, in this study, as well as applied bearing load, the dynamic response and critical speed have been used to calculate the dimensions of journal bearings.

In the field of rotating machine, especially a heavy-dutyrotating machines, the critical speed and response are the main parameters that specify bearing dimensions.

The bearing aspect ratio (bearing length to borediameter) and bearing clearance have been determined based on rotor maximum critical speed and minimum response displacement.

The analytical solution of rotor Eq.

of motion was verifiedby numerical solution via using ANSYS Mechanical APDL 18.0 and by comparing the numerical solution with the precedingstudy.

The final study results clearly showed that the bearing aspect ratio has little effect on the critical speed, but it has a high effect on the dynamic response also the bearing clearance has little effect on the critical speed and considerable effect on the dynamic response.

The study showed that the more accurate values of bearing aspect ratio to make the response of rotor as lowas possible are about 0.65 -1 and bearing percent clearance is about 0.15 -0.2 for different rotor the numerical solution with the precedingstudy.

The final study results clearly showed that the bearing aspect ratio has little effect on the critical speed, but it has a high effect on the dynamic response also the bearing clearance has little effect on the critical speed and considerable effect on the dynamic response.

The study showed that the more accurate values of bearing aspect ratio to make the response of rotor as lowas possible are about 0.65 -1 and bearing percent clearance is about 0.15 -0.2 for different rotor dimensions