Patent ID: 6989676
Filing Date: 2006-01-24
Classification: G01N

Abstract:
1. A method of detecting soot and water content in diesel engine oil having a dielectric constant, the method comprising: measuring a change in the dielectric constant in a first frequency band; measuring a change in the dielectric constant in a second frequency band; using the measured changes in the dielectric constant in the first frequency band and the second frequency band to calculate the water content in the oil; using the measured changes in the dielectric constant in the first frequency band and the second frequency band to calculate the soot content in the oil; and using an imaginary part of the dielectric constant to calculate the soot content in the oil by determining the ratio of the difference between an oscillator tuning voltage generating a first standing wave passing through a portion of the oil having a first soot content and an oscillator tuning voltage generating a second standing wave passing through a portion of the oil having a second soot content over a null voltage level measured for the oil having the second soot content.