Ralph E. Kornbrekke

Chemical sensor development for measuring soot caused lubricant oil thickening

Soot caused oil thickening is a known failure mode for lubricants operating in heavy-duty diesel engines. An integrated chemical sensor has been developed. It consists of a bulk acoustic wave quartz resonator and a capacitor formed between a grounded electrode of the quartz resonator and an additional electrode. Two series of engine oil drain samples were tested and the temperature effect on soot agglomeration was investigated. Different methods for diagnosing the real time oil condition and predicting the oils residual useful life are proposed.

Sludge Formation in Engine Testing and Field Service

The relationship of engine test sludge to field sludge was investigated by a variety of analytical techniques. Engine oil drains and sludges are suspensions of aggregated, resinous particles in oil. The sludges, in particular, contain large particle networks which are readily broken under shear. The resinous phase itself contains highly oxidated fuel fragments, and is enriched in aromatics, acidic species, and additive elements relative to the bulk oil. Field sludge and drain oil samples from the U.S., Europe, and the Far East are shown to be chemically similar to sequence VE engine test sludge and drain oil. Fleet test drain oils from vehicles powered by the Daimler Benz M102E engine are shown to be chemically similar to M102E engine test drain oils.

High temperature reactions of metal carbonates with a model metal surface

Abstract The decomposition and reaction of metal carbonates on the surface of iron to form ferrites has been investigated. The interaction of carbonates as pure inorganic solids or as non-aqueous sols with ferric oxide has been analyzed at high temperatures using TGA and XRD.