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Computational fluid dynamics simulations of the gas exchange process in a crankcase-scavenged, two-stroke engine were used to study the scavenging characteristics of the engine over the whole operating range and to investigate the effects of various design changes. The simulations used time-dependent velocity and pressure boundary conditions in the transfer and exhaust ports, respectively, which were obtained from a one-dimensional gas exchange code. The bulk flow characteristics, scavenging and trapping efficiencies, computed from these simulations compared well with experimental data. Investigation of the highest load and speed case showed that moderate port angle variations only weakly influenced the scavenging efficiency and velocity field. On the other hand, modifying the exhaust pressure to simulate single cylinder operation had a more significant effect on the scavenging and showed a possible way to control the gas exchange process.

Application of Atmospheric Pressure Chemical Vapor Deposition (APCVD) to the production of thin film coated glass is addressed in this study. Several layers of thin solid film are deposited on the surface of the glass as it moves underneath the APCVD applicator system at high temperature. High velocity in the vicinity of the deposition zone is desirable. Two separated regions of recirculating fluid are generated as the fluid jet exits the injector. The memory effect in the form of thickness streaks, corresponding to the location of the inlet holes located upstream in the upper manifold feed channel, are evident on the thin film. Also, the velocity field in the injector channel is influenced by the location of the holes. This nonuniform gas flow across the glass causes a color variation of the coating. Effective mixing of the gas streams is required to treat the hole memory problem. However, premature reaction is to be avoided.

The current ability of the Virtual Aerodynamic/ Aeroacoustic Wind Tunnel to predict interior vehicle sound pressure levels is demonstrated using an automobile model which has variable windshield angles. This prediction method uses time-averaged flow solutions from a lattice gas CFD code coupled with wave number-frequency spectra for the various flow regimes to calculate the side window vibration from which the sound pressure level spectrum at the driver's ear is determined. These predictions are compared to experimental wind tunnel data. The results demonstrate the ability of this methodology to correctly predict wind noise spectral trends as well as the overall loudness at the driver's ear. A more sophisticated simulation method employing the same lattice gas code is investigated for prediction of the time-accurate flow field necessary to compute the actual side glass pressure spectra.