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The effect of fuel injection pressure on the brake specific fuel consumption (BSFC) and brake specific particulate matter (BSPM) emissions at NOx parity (constant NOx emissions level) was investigated under different conditions of engine speed and load using a 2.5L DDC/VM-Motori common-rail, turbocharged, direct injection (DI), light-duty diesel engine. NOx parity at varying conditions of speed, load, and fuel injection pressure was achieved by changing the injection strategy and timing. The results of these analyses confirmed the well-established trends that soot emissions reduce with an increase in rail pressure at the expense of increasing NOx emissions. With an increase in engine speed (at constant load and NOx parity), it was observed that BSFC, CO, CO₂, and hydrocarbon emissions decreased, while BSPM decreased initially and increased later on. Increasing the fuel injection pressure resulted in an increase in BSFC, CO, CO₂, and hydrocarbon emissions.

This paper develops a set of seven general equations which describe various portions of a standard engine performance chart. A regression analysis technique is then employed to evaluate the constants in these equations which identifies them to a particular engine. Computer programs which employ this technique are provided. A final program is provided which utilizes the equations to yield a value of brake horsepower for an input of any combination of RPM, manifold air pressure, air temperature, and pressure altitude.

THE bypass or ducted-fan turbojet engine is a highly controversial aircraft powerplant. It is hoped that this presentation of its operating principles will lead to a more rational understanding of the pros and cons of the issue. Discussion is explicitly limited to transport aircraft applications at speeds in the neighborhood of 500 mph. Noise, duct losses, boundary-layer intake, and structural considerations are all shown to be important. It appears that a comprehensive design development of bypass or ducted-fan engines in connection with aircraft aerodynamics and structure poses a serious problem in the field of high-subsonic-speed transport aircraft.