Using bottom outlets for drain and regulation of water level in reservior has significant importance in performance mahagment of dam. Amount of service and emergency gates opening have important role in pressure, velocity and discharge coefficient variations and finally dam performance. In the present research, flow aeration between emergency and service gates was studied with different hydraul...

In this study an extensive experimental research is carried out to develop a better understanding of the effects of Piano Key (PK) weir geometry on weir flow threshold submergence. Experiments were conducted in a 12 m long, 0.4 m wide and 0.7 m deep rectangular glass wall flume. The main objectives were to investigate the effect of the PK weir geometries including the weir length, weir height, ...

Critical submergence in pumping systems can be determined using a number of calculations, all of which result from heterogeneous geometries based on water. The most widely spread critical submergence formula is that of the Hydraulic Institute. A study, carried out in Germany, looked at eight different formulations used to calculate critical submergence, comparing their results with those of a h...

in this study digital image correlation (dic) technique combined with a high speed video system was used to predict movement of particles in a water model. comparing with particle-image velocimetry (piv) technique, it provides a low cost alternative approach to visualize flow fields and was successfully employed to predict the movement of particles in a water model at different submergence dept...

Responses of bald cypress (Taxodium distichum) and pond cypress (Taxodium ascendens) saplings in photosynthesis and growth to long-term periodic submergence in situ in the hydro-fluctuation zone of the Three Gorges Dam Reservoir (TGDR) were studied. Water treatments of periodic deep submergence (DS) and moderate submergence (MS) in situ were imposed on 2-year-old bald cypress and pond cypress s...

Experiments have examined the phenomenon of direct contact condensation when steam is injected vertically into subcooled water pool. The investigation carried out by varying mass flow rate and submergence depth injection pipe in range 10–50 kg/h 1–13 cm, respectively. behavior bubble that appeared at outlet, transient heat transfer coefficient, pressure variation pipe, its associated frequency ...

Abstract Inlets/outlets have bi-directional characteristics and complex structures, which important implications for practical operational safety efficiency. In this paper, the hydraulic of lateral inlet/outlet a pumped storage power station are studied by means model tests. The flow velocity distribution at leading edge orifice barrage section is more uniform, left, middle, right each same. fo...

Rainfed lowland rice ecosystem is affected not only by water deficit but also by excess water leading from partial to complete submergence. Although the rice plant is well adapted to aquatic environment, it is unable to survive if completely submerged in water for several weeks. Damage to rice plants due to excess water has been advocated to occur during submergence and also on entry of oxygen ...