The fluid state on a sieve tray will change when the towers tilt under wind loads. A computational fluid dynamics (CFD) model was used to predict the flow patters and hydraulics on the tray under different inclinations. The gas and liquid phases are modelled with the volume-of-fluid (VOF) framework as two inmiscible phases. Several three-dimensional transient simulations were carried out for a 0.38m diameter tray with varying liquid weir loads and inclined angles. The clear liquid height determined from these simulations is in reasonable agreement with experimental measurements carried out for air-water in a round tray of the same dimensions. The simulation results show that, compared with the horizontal tray, the circulation area is bigger when the liquid flow and inclination direction of the tray are the same, but when they are opposite the circulation area is smaller. The percentage of circulation area to the tray area can obviously be decreased, along with increasing liquid weir loads. It is concluded that CFD can be used for the prediction of liquid flow on sieve trays under different inclinations

Análisis estadísticos, un diagrama de Piper, el índice de saturación y la correlación de los parámetros químicos fueron utilizados para revelar la hidrogeoquímica y la evolución hidrogeoquímica de las aguas subterráneas poco profundas en la parte sur de la sección Zhongwei en la planicie aluvial del río Amarillo. La calidad del agua para el uso doméstico y agrícola también fue evaluada en este estudio. Los resultados sugieren que las aguas subterráneas poco profundas en el área de estudio son entre frescas y moderadamente mineralizadas. Un índice mayor de Ca2+ y HCO3- se observó en las aguas menos mineralizadas, mientras que Na+ y SO4(2-) son iones comunes en las aguas altamente mineralizadas. Los perfiles hidroquímicos predominantes para las aguas subterráneas con Total de Sólidos Disueltos (TDS) <1 g/L son HCO3-Ca·Mg y HCO3-Ca·Na·Mg, y para las aguas subterráneas con TDS >1 g/L, SO4·Cl-Na y SO4·Cl-Na·Mg·Ca. Las mayores reacciones en el sistema de aguas subterráneas son la disolución/precipitación de yeso, fluorita, halita, calcita y dolomita. El intercambio de cationes también es importante en el control de la química de las aguas subterráneas. Las muestras de agua evaluadas en este manuscrito son de calidad aceptable para el uso agrícola, pero la mayoría no son aptas para el consumo humano. El índice TDS, la dureza total del agua (TH), Cl- y SO4(2-) son las razones principales que influyen en la baja calidad de esta agua.

Statistical analyses, a Piper diagram, the saturation index and the correlations of chemical parameters were used to reveal the hydrogeochemistry and hydrogeochemical evolution of shallow groundwater in the southern part of the Zhongwei section of the Yellow River alluvial plain. The water quality for agricultural and domestic uses was also assessed in the study. The results suggest that the shallow groundwater in the study area is fresh to moderately mineralized water. Higher Ca2+ and HCO3- are observed in the less mineralized water, whereas Na+ and SO4(2-) are common ions in the highly mineralized water. The major hydrochemical facies for groundwater with total dissolved solids (TDS) <1 g/L are HCO3-Ca·Mg and HCO3-Ca·Na·Mg, and for groundwater with TDS > 1 g/L, SO4 ·Cl-Na and SO4·Cl-Na·Mg·Ca are the predominant hydrochemical types. The main reactions in the groundwater system are the dissolution/precipitation of gypsum, fluorite, halite, calcite and dolomite. Cation exchange is also important in controlling the groundwater chemistry. The water samples assessed in the paper are of acceptable quality for agricultural use, but most of them are not fit for direct human consumption (drinking). TDS, total hardness (TH), Cl- and SO4(2-) are the main indices that result in the poor drinking water quality.