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Frictional characteristics of several automatic transmission fluids (ATF's) were evaluated in an SAE No. 2 Friction Machine adapted to the band clutch from a front-wheel-drive, three-speed automatic transaxle. The bench test apparatus subjects the band clutch to repeated engagements (24 000 in a 100-hour test period) at elevated temperature with representative clutch energy dissipation and lockup time, and with forced aeration of the fluid. Fluid frictional performance is judged from the level and stability of friction torque during the 24 000 clutch engagements. The test is repeatable and readily distinguishes fluids having different frictional characteristics. Fluid frictional behavior in the band machine is shown to reflect fluid effects on shift performance in an engine dynamometer, transaxle cycling test. Also, fluid effects determined in the cycling test are shown to match those obtained in a vehicle.

Methanol, a popular alternative fuel candidate, can theoretically be dissociated on-board a vehicle into a 2/1 molar mixture of hydrogen (H2) and carbon monoxide (CO) having a 14 percent greater heating value than that of methanol vapor. In this study, engine efficiency and fuel consumption with methanol vapor and dissociated methanol (simulated by a 2/1 mixture of Ha and CO) were compared in a single-cylinder engine at equivalence ratios (Φ’s) ranging from 0.5 to 0.9 and compression ratios (CR’s) from 11 to 14. Whan compared at the same Φ and CR, the reduction in fuel consumption for dissociated methanol compared to methanol (3-7 percent) was smaller than would be expected based on heating value alone. Indicated thermal efficiency with dissociated methanol was only 0.89-0.55 times that with methanol. Thermodynamic analyses were conducted to isolate the factors responsible for lower efficiency with dissociated methanol.