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This paper presents a programmable E/H control valve consisting of five individually proportional flow control valves. With a hybrid control algorithm, this valve has programmable valve characteristics, such as adjustable valve deadband and flow control gain, and programmable valve functions, such as different center functions. System analyses and experimental evaluations indicate that this programmable valve is capable of replacing conventional E/H control valves in practical applications.

Environmental concerns have obstructed development of new landfill sites making it essential to efficiently use currently available space. Finite element methods are evaluated for predicting densification by compactors with the intent of eventually optimizing vehicle design with respect to compaction. A geometrically non-linear, plane strain, quasistatic analysis is used to capture the effects of a single rigid wheel. Future work will include multiple wheels and successive passes, three-dimensional simulations, and realistic material characterization.

This paper describes and discusses a computer model that can be used to predict the hydraulic pump requirements of an excavator necessary to meet the specified productivity levels for a given set of design conditions. The model predicts the hydraulic cylinder flow rates, pressures, and power necessary to sustain a given work cycle. The study compares the results from a simulation of the excavator with actual test data obtained from a test vehicle taken during a typical work cycle.

A normally aspirated, four-stroke diesel engine was tested under operation with two alcohol containing fuel blends. The fuels contained ethanol, butanol, heavy virgin distillate, diesel Nos. 2 and 4, and a cetane improver. The proportions of the components were selected to give blends with properties within the range of diesel No. 2. The final blends contained 25 and 43.7 percent alchohols. Test results showed a loss in power due to the reduced heating value of the blends, and some deterioration of performance at light loads. At intermediate to heavy loads, satisfactory performance was obtained.