Tracer responses in gas-liquid, two-phase flow through a fractured layer are discussed. Experiments were carried out using a glass bead bed in a cylinder. In the results, over a wide range of flow conditions of particle size, fluids-flow velocity, and water saturation (Sw), one of three types of liquidand gas-flow pattern was obtained: a single-phase (water) flow with entrapped gases, a bubble ...

the effect on sugar beets of water and nitrogen movement in the soil under different water conditions was assessed over two years (2000-1) at the khorasan agricultural research center. three water treatments (no water stress, continuous stress and primary stress) and three n amounts (80, 160 and 240 kg n/ha) were investigated. the amount of moisture depletion in the water treatments was 50%, 80...

dam reservoirs supplies water resources for drinking, agriculture, and industry almost in all parts of iran. lack of proper utilization rules and unbalanced demands versus available water has led to many problems regarding to ineffective use of the water resources. precipitation and flow rate are stochastic phenomena. therefore, multi-step processes related to the water use efficiency should be...

abstract stepped spillways are of most important hydraulic constructions to dissipation energy of water flow. these constructions are used in opening channel to transfer water from upper level to lower level. because of considerable effect of steps on flow dissipation energy and also the resulted developments in construction of roller competed concrete rcc, the mentioned constructions have draw...

China’s development over the last few decades has been characterized by high rates of economic growth, large-scale migration from rural areas to the fast-growing cities accompanied by changes in lifestyles, and steady population growth. These developments have left deep marks on resource availability and quality. In this article we conduct a scenario analysis of how lifestyle changes and other ...

The combined sewer system of the City of Prague, similar to other relevant locations, is strongly affected by infiltrating waters. The knowledge of their volume is one of the important parameters with respect to sewer system operation, maintenance and reconstruction. The methodology is based on the variation of diurnal chemical oxygen demand (COD) load and continuous water quality monitoring us...

Internal pipeline corrosion in oil production and transportation is always associated with the presence of water, and the likelihood of corrosion generally increases with the volume fraction of water. When the walls of the pipeline are wetted with oil no corrosion is possible. Highly turbulent flow was associated with negligible corrosion due to water entrainment by the flowing oil, whereas low...

Conventional wastewater collection systems are installed to remove human wastes from households in cities and urban areas. This system demands high water supply rates as the wastes are flushed through pipes using water that flows under gravity. This system is capital extensive, and has been found to be not suitable in urban areas with smaller population sizes. Also, for the same reason, not sui...