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The flow of diesel fuel through multi-hole injection nozzles is well understood. There are, however, no comprehensive experimental results for the design of injection nozzles for alternate fuels. A steady state flow generator was designed and employed to analyze the effects of the physical fuel properties and the needle lift on the discharge coefficient for the nozzle orifice. Three fuels were tested: diesel reference fuel, a 50/50 mixture of diesel fuel and sunflower oil, and 100%. sunflower oil. The fuel viscosities range from 3.0 cS to 30.0 cS at 40°C. Five injection pressures ranging from 3.5 to 13.8 MPa, and eight increments of needle lift between 0.031 and 0.940 mm were used in this investigation. A significant influence of needle lift, injection nozzle pressure, and physical properties of fuels on the flow coefficient in the normal operating range of a typical diesel engine was proven.

Five T31 turbochargers used on a direct-injected diesel engine were tested as part of a plant fuel evaluation program. The engine was tested on the 200-hour durability cycle proposed by the Engine Manufacturer's Association (EMA). Part of the evaluation was an investigation of premature carbon and lacquer deposits, and wear within the turbocharger due to oil deterioration from the hybrid fuels. The lubricant viscosities for all tested fuels, except the microemulsion, were within normal limits. A sudden increase in lubricating oil viscosity for the microemulsion was observed. At the same time, higher blow-by and increased lubricating oil consumption was noted. All turbochargers displayed journal bearing wear but no rubs or unusual seal leakage was formed. The turbine shafts showed various degrees of hot shutdown and high temperature operation for different fuels. The turbine wheels and housings varied in color from a soft gray to dark black.