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This paper reports on research results to correlate the motion of the drops on fibers. The drag coefficient for axial motion of barrel drops on fibers is correlated to the Reynolds, Capillary number and the drop to fiber diameter ratio. The correlation is fitted to the experimental data. The experimental data are obtained from a special made couette flow apparatus. The apparatus is designed to hold the fiber steady using cylindrical wires and the drops are attached to the fibers by exposing them to a liquid aerosol stream. The air flow is applied parallel and perpendicular to the fiber axis to measure motion of drops axially along the fiber and the rate of drop detachment for flow perpendicular to the fiber. Drop motion on fibers occurs in numerous industrial, automotive, and aerospace applications. The correlations developed in this work will be useful in modeling and predicting drop motions.

This paper presents experimental results of studies investigating the effect of nitric oxide (NO) on the autoignition chemistry of a primary reference fuel blend with an octane rating of 87 in a motored engine. The experiments were conducted over a range of operating conditions in a single cylinder research engine at compression ratios of 5.2 and 8.2. The inlet manifold was heated and supercharged to pre-stress the fuel-air mixture in order to produce in-cylinder pressure and temperature histories similar to practical engines. The exhaust gas carbon monoxide concentration was monitored and used as a measure of overall reactivity. In-cylinder pressure histories were also recorded and processed to calculate in-cylinder temperature histories. Results showed that at low manifold temperatures, below that necessary to produce negative temperature coefficient behavior, up to 100 ppm of NO promoted reactivity, whereas higher concentrations retarded the reactivity.

Sequential four-ball wear tests have been used to evaluate automotive crankcase oils for use as heavy-duty hydraulic fluids and automotive crankcase lubricants. This test technique has been adapted for use with steel-on-steel, steel-on-ceramic and ceramic-on-ceramic bearing systems. In addition to the conventional “run in” and “steady-state” wear studies, the data produced have been used to interpret bearing unit load levels for the various bearing systems involved. The data produced show that in many cases hybrid bearing systems (steel-on-ceramic) and ceramic-on-ceramic bearing systems may be useful at higher unit loadings than the conventional steel-on-steel systems. These studies focused on achieving low boundary lubricated wear rates. The bearing unit loadings were obtained from the unit bearing pressures after the “run in” of the specific bearing system.