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The purpose of these experiments was to determine the performance of a turbocharged rotary engine at power levels above 75 kw (100 hp). A twin rotor turbocharged Mazda engine was tested at speeds of 3000 to 6000 rpm and boost pressures to 7 psi. The NASA-developed combustion diagnostic instrumentation was used to quantify IMEP, PMEP, peak pressure and face-to-face variability on a cycle-by-cycle basis. Results of this testing showed that at 5900 RPM a 36 percent increase in power was obtained by operating the engine in the turbocharged configuration. When operating with lean carburetor jets at 105 hp (78.3 kw) and 4000 RPM, a brake specific fuel consumption of 0.45 lbm/lb-hr was measured.

A two-dimensional, implicit finite-difference method of the control-volume variety, a two-equation model of turbulence, and a discrete droplet model have been used to study the flow field, turbulence levels, fuel penetration, vaporization and mixing in Diesel engine-type environments. Good agreement with the droplet penetration data of Hiroyasu and Kadota has been obtained for a range of ambient pressures neglecting the effects of void fraction, droplet coalescence and droplet collisions in the simulation. The model has also been used to study the effects of the intake swirl angle on the flow field, turbulence levels, fuel penetration, vaporization and mixing in a two-stroke Diesel engine operating under motored conditions. Numerical simulations indicate that as the intake swirl angle is increased, the fuel penetration, vaporization and mixing increase.

The effects of mixture stratification at the intake port and gaseous fuel injection on the flow field and fuel-air mixing in a two-dimensional rotary engine model have been investigated by means of a two-equation model of turbulence, an algebraic grid generation method and an approximate factorization time-linearized numerical technique. It is shown that the fuel distribution in the combustion chamber is a function of the air-fuel mixture fluctuations at the intake port The fuel is advected by the flow field induced by the rotor and is concentrated near the leading apex during the intake stroke. During compression, the fuel concentration is highest near the trailing apex and lowest near the rotor. The penetration of gaseous fuel injected into the combustion chamber during the compression stroke increases with the injection velocity and results in recirculation zones between the injector and the leading apex and between the injector and the trailing apex.