AN ENGINE OIL LIFE ALGORITHM

Author:

Bommareddi, Anveshan

Graduate Program:

Mechanical Engineering

Degree:

Master of Science

Document Type:

Master Thesis

Date of Defense:

November 17, 2009

Committee Members:

Liming Chang, Thesis Advisor/Co-Advisor
Liming Chang, Thesis Advisor/Co-Advisor

Keywords:

oil change interval
algorithm
operating conditions
driving conditions
simulations

Abstract:

An oil-life algorithm to calculate the remaining percentage of oil life is presented as a means to determine the right time to change the oil in an engine. The algorithm accounts for major factors that affect the engine oil life and is intended to provide a simple balance between human interference and automation to improve the reliability of oil-life prediction without affecting the engine components and their performance. The algorithm can be implemented as a simple and robust system that can be updated through timely field tests and applied to any type of engine or engine oil. The proposed oil-life algorithm takes into account, the nominal engine oil life (based on the oil grade and engine type used) and monitors engine oil temperature, coolant temperature, engine load, engine speed, engine cranking, and oil aging. The algorithm also accounts for driving in desert or dusty environment. The development of correction factors for each of these operating conditions is presented. Implementation of the oil-life algorithm as a system and its capabilities are also discussed. To evaluate the oil-life algorithm, an oil-life simulator is developed using MATLAB. Various driving conditions are simulated by generating data from the heavy duty diesel engine test data and by controlling the operating conditions according to the driving condition being simulated. The simulation results and multiple evaluations of the oil-life algorithm are broadly discussed. Comparisons with the existing practice, manufacturer’s manuals, and experimental research are also presented in order to validate the oil-life algorithm. The features and advantages of the oil-life algorithm over the existing practice are presented along with the conclusions and key results. Finally, the scope for improvement and further development is suggested.