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In the present paper, a three-dimensional numerical analysis model based on elastic deformation was applied to analyze the compression top piston ring-liner friction of heavy duty diesel engine, considering the rheological lubrication, the newton fluid model was applied to the numerical analysis. The result illuminates that the turning point of friction transforms from rigid hydrodynamic lubrication to elastohydrodynamic lubrication is around 4°∼8°CRA BTDC (crank angle before top dead center) on the compression stroke in this calculation model. In comparison, the surface elastic deformation was started near 10°CRA BTDC on the compression stroke which is significantly clearer than the lubricant elastic deformation. A friction tester was applied to verify the calculation results. The experiment proved that the model based on elastic deformation is closer to the actual situation and the calculation result at a lower temperature is more precise than that of higher temperature.

Currently, the thermal efficiency of vessel diesels only reaches 48∼51%, and the rest energy is rejected to the environment in forms of exhaust, cooling water, engine oil and so on. Meanwhile, energy is required when generating electricity and fresh water that are necessary for vessels. A system that combines the ORC thermal electric generation system with the single-effect evaporating desalination system simultaneously driven by waste heat of charge air is proposed. The research object was 12S90ME-C9.2 diesel engine produced by MAN corp., and a calculation model of the system is built by MATLAB. The variation of the output power, the thermal efficiency and the freshwater production with some operational parameters of the combined system are calculated and analyzed.

Cogeneration system has become a valuable alternative approach for cascade waste heat recovery (WHR). In this paper, a novel electricity-cooling cogeneration system (ECCS) based on organic Rankine cycle-absorption refrigeration cycle (ORC-ARC) combined system is proposed to recover the waste heat of marine engine. ORC was adopted in the higher temperature cycle, in which alternatives D4, MDM and MM were selected as the working fluids. An ARC was adopted in the lower temperature cycle to recover the heat of the working fluid at the regenerator outlet in ORC. It aims to satisfy refrigeration requirement aboard ship, in which a binary solution of ammonia-water is used as the working pairs. Electricity output, cooling capacity, total exergy output, primary energy ratio (PER) and exergy efficiency are chosen as the objective functions.

Like outside scenery, the car interior noise and road condition will affect the driver's mental state when driving. In order to explore the influence of external visual and auditory factors on the driver's mood in the driving process based on research of traffic soundscape, this paper has selected four backbone roads of Tianjin city (China) to test and drive a gasoline passenger vehicle at different speeds. Near Acoustic Holographic was used to scan interior acoustic field distribution, while the tracking shot of the driver's location was recorded by a Sony camera. People with different characteristics were invited to watch the video and completed a self-designed survey questionnaire. The external factors affecting the driver's mood were explored by analyzing all these data.

This paper presents a model system TEG-DORC that employs thermoelectric generator (TEG) as a topping cycle integrated with a dual-loop organic Rankine bottoming cycle (DORC) to recover exhaust heat of internal combustion engine (ICE). The thermodynamic performance of TEG-DORC system is analyzed based on the first and second law of thermodynamics when system net output power Wnet, thermal efficiency ηth, exergy efficiency ηe and volumetric expansion ratio are chosen as objective functions. The model has many parameters that affect combined system performance such as TEG scale, evaporation pressure of high temperature ORC loop (HT loop) Pevp,HT, condensation temperature of HT loop Tcond,HT. It is suggested that HT loop has a vital influence on system performance.