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An experimental study was conducted to characterize the dynamics and spray behavior of a wide range of minisac and Valve-Covered-Orifice (VCO) nozzles using a high-pressure diesel common-rail system. The measurements show that the resultant injection-rate is strongly dependent on common-rail pressure, nozzle hole diameter, and nozzle type. For split injection the dwell between injections strongly affects the second injection in regards to the needle lift profile and the injected fuel amount. The minisac nozzle can be used to achieve shorter pilot injections at lower common-rail pressures than the VCO nozzle. Penetration photographs of spray development in a high pressure, optical spray chamber were obtained and analyzed for each test condition. Spray symmetry and spray structure were found to depend significantly on the nozzle type.

The design of a transmission for heat engine-battery hybrid vehicles, the Electromechanical Transmissions, is described. Results of the testing of a breadboard EMT power train on a dynamometer are discussed in terms of emission reduction, fuel consumption, and power flow efficiencies. Sources of system inefficiency and areas of further investigation are identified.

An analysis was carried out to determine the design requirements and performance characteristics of a hybrid vehicle containing an internal combustion engine, batteries, generator, traction motor, and power conditioning. Consideration of urban and high speed highway operation leads to special requirements for a high power density battery. Detailed modeling and simulation of power train components and their interfaces on an analog/digital computer allowed an evaluation of the total vehicle system when driven in urban traffic. Results show that presently available components or those which could be developed in the near term can be combined to make an attractive vehicle propulsion system offering improved fuel economy.