A conceptual design of the thermoelectric power conversion system combined with open rack type LNG (liquefied natural gas) vaporizer to make use of cold heat of LNG is presented. The system performance analysis has been made based on the thermoelectric module performance data obtained at the cryogenic thermoelectric (CTE) test rig which could realize temperature and fluid dynamic condition of the open rack type LNG vaporizer. Conventional bismuth-telluride thermoelectric modules were tested, however, each module is encapsulated in the stainless steel container to achieve water proof. Electricity production cost evaluation of the system is also discussed.

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In this paper we report on the newly developed framework MADS (Multi-Agent Diffusion Simulation), designed for simulating the diffusion of innovations. Created for but not limited to the simulation of the diffusion of emergent technologies, MADS is both close to the diffusion theory and, by using a distributed agent infrastructure, performs data management and streamlines the simulation process. After presenting the framework, we show how it was applied to the simulation of the diffusion of fuel cell vehicles. Unlike the traditional simulation methods usually employed in this case, real consumer preferences are included and a sensitivity analysis is performed.

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Pool boiling CHFs for a highly wetting liquid due to steady state and transient heat input were studied. Boiling heat transfer processes on a platinum cylinder in a pool of ethanol due to exponentially increasing heat inputs, Q=Q₀exp(t/τ), ranging from quasi-steadily increasing one to rapidly increasing one with periods, τ were measured for a 1.0-mm diameter horizontal cylinder with different surface roughness of commercially-available or roughly-finished surface cylinders for saturated and subcooled liquid at various pressures. Steady-state CHFs at various pressures gradually increased with an increase in subcooling. It was confirmed that the CHFs for lower subcoolings at every pressure almost show little dependence on surface roughness. However the CHF data for the roughly-finished one in many cases were increased for higher subcoolings over pressures. Typical trends of the CHFs were clarified to three groups corresponding to periods: the 1st, 2nd and 3rd groups of CHF were for longer periods, for shorter and for intermediate ones, respectively. It was clarified that the transient CHFs belonging to the 2nd and 3rd group were significantly affected by the surface roughness of cylinders. It appears that more study on the multi-parametric surface roughness and a wider range of experimental conditions need to be included in the study.

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This paper investigates the effect of blade deformation, caused by manufacturing inaccuracies, on the performance of a 2-stage axial steam turbine. A high fidelity 3D coordinate Measurement Machine has been employed to obtain the exact geometrical model of the blades. A Streamline Curvature solver was used to predict the overall performance of the turbine. During the manufacturing process of the casts and of the blades themselves, several types of errors can occur which lead to a different geometry from that envisaged by the designer. The main objective of this study is to investigate the effect of those errors on the performance of a 2-stage experimental axial steam turbine. A high fidelity measurement of the actual geometry of both stator and rotor blades has been carried out, using a 3D Coordinate Measurement Machine. The cross sections of the blades obtained by the measurement were compared with those produced by the design process to evaluate the change in blade inlet/exit angles. In addition, the geometrical deviations from the initial design have been subjected to a statistical study in order to locate the nature of the error. The actual (measured) model has been used as input into a Streamline Curvature solver to evaluate its performance. Finally, a comparison with the performance plots of the original geometry has been carried out. A measurable change of efficiency as well as in the total power delivered by the turbine was found. This suggests that the accumulated error caused during the manufacturing procedure plays a significant role in the overall performance of the machine by making it less efficient by more than 1%. Reverse engineering techniques can be applied to predict and alleviate these errors leading thereby to a final design of each stage with improved performance.

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In the first phase of the present study, the pyrolysis oil derived from light automotive tire waste has been characterized including fuel properties, elemental analyses, FT-IR, ¹H-NMR, GC-MS and distillation. The studies on the oil show that it can be used as liquid fuel with a gross calorific value (GCV) of 42.00 MJ/kg and empirical formula of CH_1.27O_0.025N_0.006. In the second phase of the investigation, the performance of a diesel engine was studied blending the pyrolysis oil with diesel fuel in different ratios. The experimental results show that the bsfc of pyrolysis oil-diesel blended fuels slightly increases and hence the brake thermal efficiency decreases compared to those of neat diesel. The pyrolysis oil-diesel blends show lower carbon monoxide (CO) emission but higher oxides of nitrogen (NO_x) emissions than those of neat diesel. However, NO_x emissions with pyrolysis oil-diesel blended fuels reduced when EGR was applied.

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