The modified Reynolds equation for power-law fluid is derived from the viscous adsorption theory for thin film elastohydrodynamic lubrication (TFEHL) of circular contacts. The lubricating film between solid surfaces is modeled as three fixed layers, which are two adsorption layers on each surface and a middle layer. The differences between classical EHL and TFEHL with power-law lubricants are discussed. Results show that the TFEHL power law model can reasonably calculate the pressure distribution, the film thickness, and the velocity distribution. The thickness and viscosity of the adsorption layer and the flow index significantly influence the lubrication characteristics of the contact conjunction.

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This research revolves around the ventilation system of range hoods and discusses the optimization of the flow field from the perspectives of reverse engineering (RE), the Taguchi method (TM), and computer aided engineering (CAE). These were integrated to develop an impeller system with an optimized air discharge volume. Analyses show that the arc length of the blades and the deflection angle of the impellers are the most prominent factors affecting the volume of the air discharge. A maximum air discharge volume was achieved during the experiment with 54 blades and a deflection angle of [Formula: see text], which is an enhancement of 17.5% in comparison with that of the original design. In an environment with shortened product life cycles, the results from this research are expected to improve the air discharge efficiency of impellers and effectively reduce the time needed for the development of ventilation systems.

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Carbon nanotubes (CNTs) were fabricated in air using the electrical discharge machining method. The main parameters for this process were substrate temperature, peak current (Ip), and pulse duration (τ). The substrate was baked at 50°C and this temperature was maintained for 12 h under vacuum chamber; it was then cooled to room temperature and stored in vacuum for outgassing. During single-pulse discharge in air, the substrate was heated from room temperature to the test temperatures (50 and 70°C). The results indicated that the length, density, and purity of CNTs grown on outgassed substrates were better than those of CNTs grown without outgassing. Additionally, CNTs grown withIp= 3 A andτ= 1200 μs were of better quality than those grown with other combinations of parameters. The size of the discharge pit was effectively reduced by 30% (80 μm). This finding may help in controlling the amount of peak current used during the process, thereby reducing the problems of heat-affected zones and electrode consumption. Consequently, there was substantial improvement in the zonal selectivity and reticular density of the CNTs grown using the single-pulse discharge method.

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