Online Detection of Water and Coolant in Engine Oil

Open Access
Fecek, David Patrick
Graduate Program:
Mechanical Engineering
Master of Science
Document Type:
Master Thesis
Date of Defense:
March 31, 2017
Committee Members:
  • Dr. Liming Chang, Thesis Advisor
  • oil analysis
  • oil
  • water contamination
  • coolant contamination
  • oil contamination
  • water
  • coolant
  • glycol
  • engine oil
  • condition based maintenance
  • online detection
  • condition monitoring
  • engine health
  • engine monitoring
An online fluid property sensor was used to analyze the effects of small amounts of water and glycol-based coolant contamination in engine oil. The sensor measures the dynamic viscosity, density, and dielectric constant of the oil using quartz tuning fork resonator technology. Due to the difficulties of measuring water and coolant contamination effects related to immiscibility, experiments were developed that would mitigate these issues. Sub-saturation levels of water contamination were introduced to oil via humid air in an environmental chamber. Oil property and water content data was collected as the oil approached equilibrium with its surroundings. A compact flow loop was also built to emulate an engine lubrication system. Both water and coolant were introduced in increasing quantities and the effects were recorded. It was found that only the dielectric constant of the oil showed sensitivity to water and coolant contamination using this method of measurement. The magnitude of the changes seen for contamination levels below condemning limits was minimal, potentially too low for confident detection in an operating engine system. Further contamination beyond condemning limits was shown to increase the magnitude of the changes seen, leading to a greater potential for detection.