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The contributions of vibration sources in a gasoline direct-injection (GDI) engine are identified by simulating a two input-one output model. A partial coherence function between two inputs and one output was calculated to identify the contributions of the two inputs to the output. In order to evaluate the proposed method, a principle test was performed using a laboratory test rig. The results show that the model can be used to identify the contribution of each input to the output. Finally, this model is applied to the identification of the vibration source in a GDI engine.

The purpose of this research was to investigate the extent to which the thermal conductivity of non-Newtonian fluids is affected by fluid motion under conditions in which it is known that the viscous properties undergo significant changes, and then the effect of these shear rate dependent thermal conductivity measured in Lee [1995], on the heat transfer for a typical convective system. A coaxial cylinder apparatus with a rotating outer cylinder was used for the determination of the thermal conductivity of non-Newtonian liquids in a shear field. A simple parallel plate flow model with temperature independent properties gave increases in heat transfer of the order of 30--80% over the entire temperature range (20°C--50°C) of CMC solutions depending on the inlet average velocity due to the effect of the shear dependent thermal conductivity.

This paper examines the effects of viscous heating in the flow of Newtonian and non-Newtonian fluids. Two system were analyzed theoretically. One uses a Couette Flow model between two infinite parallel plates. The other examines Couette flow between concentric cylinders (infinite in length). It is found that, for the thermal boundary condition of constant wall temperature, the generalized Prandtl number (Prg) is the parameter which indicates whether or not viscous heating effects are important.