A Review of the Remaining Useful Life (RUL) Concept in Rotating Machinery Utilizing Prognostics and Health Management (PHM) Approach

Maintenance is one of the most important elements in any industry. Next to manufacturing, it probably has utmost importance in the production of industrialgoods.It has even higher priority when rotary machines are used. Having an appropriate algorithm for maintenance can prevent human and financial problems in such industries. In recent times, various methods of remaining useful life (RUL) prognosis have been proposed for rotary machines, but there is not a comprehensive review article that can well differentiate different methods. Herein, after describing the meaning of remaining useful life, the three most commonly used prognosis methods, including data-driven approach, model-based approach and hybrid prognostics approach, are elaborated upon. Subsequent to that, concept and mathematics of RUL in rotary machines for each method, have been discussed. Toward the end, there are constructive suggestions for researchers in this field in terms of dealing with RUL and PHM.