prediction of the low to moderate rpms for rotating shafts via free surface profile measurement – an experimental study

One of the challenging issues in any sectors of industry, research and development sectors is accessing the actual rpm of rotating machineries. therefore, in this study a combination of simple but flexible experimental set up, and a theoretical analysis is employed to measure the rpm of a rotating motor. the procedure is separately tested on a motor, rotating water and motor oil containers at different rpms. the results indicated very promising results with minor errors of 0.02% and 1.88 % for water and motor oil rotation respectively.