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In order to avoid the corrosion risk caused by the internal water in the pipeline, the transnational long distance crude oil pipeline carries out the accumulated water in the low-lying part of the topographic undulating pipeline through the flow of the crude oil itself. According to the characteristics of oil-water two-phase flow state and oil-water interface morphology in upward crude oil pipeline, Open- FOAM software was used to simulate and analyze the oil-water interface. InterFoam solver based on VOF model was selected to solve the dynamic equation of oil-water interface. The experimental data and numerical simulation results under the same conditions are compared and verified. The results show that the method of simulating the water carrying flow with OpenFOAM was feasible. The oil-water interface of upward inclined pipeline is related to the wettability of the wall. When the contact angle θ is 30° (hydrophilic wall surface), the oil-water interface appears wave shape, and when the contact angle θ is 120° (hydrophobic wall surface), the water accumulates into water mass on the upward inclined pipe. The flow rate of water increases with the increase of contact angle θ and crude oil velocity, and when the flow rate of crude oil exceeds the critical velocity of Kelvin-Helmholtz interface fluctuation, it will lead to the accelerated movement of water. [ABSTRACT FROM AUTHOR]

Abstract: Water distributions of a polymer electrolyte fuel cell (PEFC) with 9-parallel channels during operation were visualized using a neutron radiography facility at B4 port in KUR (Kyoto University Research Reactor). An imaging system with a neutron image intensifier (I.I.) was employed for reducing the exposure time, and the water distributions in the in-plane and through-plane directions in the PEFC were alternately obtained every 20sec. The accumulation processes from the GDL to the channels were confirmed. Water accumulated in the GDL at the cathode and evacuation into the channels started around 5min. Water tended to accumulate at the edge of the ribs, and accumulated as water drops in the channels. The size of the water drops grew up to 1mm which was the same size as the channel width and height, and the cell voltage was decreased because the liquid drops disturbed the air supply. [Copyright &y& Elsevier]

Abstract: Lake Cerknica is an intermittent wetland with seasonal water level fluctuations. This paper discusses the possible changes of ecosystem services due to altered ecosystem functions caused by regional climate change. For this purpose, the lake''s water regime was analysed and biomass production of common reed (Phragmites australis), the prevailing species, was related to ambient temperatures and water level. The effect of the latter was also examined for reed transpiration rate and plant diversity. The results revealed a gradual loss of seasonality of floods and droughts. High water level in winter months and temperatures at the beginning as well as the end of vegetation period were found to have a significant influence on reed biomass. The plant diversity research in six subsequent years in three different aquatic habitats revealed trends of a decrease due to increased water depth during the vegetation period. The complexity of the system and consequently ecosystem services might also be affected due to changes of other processes, which revealed to be related to water level; namely transpiration rate, plant mycorrhizal colonisation and soil mineralisation. [Copyright &y& Elsevier]