Search results for "Channel width"
showing 4 items of 4 documents
Dimensional analysis and stage-discharge relationship for weirs: a review
2017
Deducing the weir flow stage-discharge relationship is a classical hydraulic problem. In this regard Buckingham’s theorem of dimensional analysis can be used to find simple and accurate formulas to obtain the rating curves of different weir types. At first, in this review paper the rectangular weir that is a very common hydraulic structure is studied. It is indicated that the crest shape, approach channel width, obliquity (angle between the weir crest and the direction normal to the flow motion) and vertical inclination (pivot weir) are the key-parameters affecting the flow over the rectangular weirs. The flow over the triangular, labyrinth, parabolic, circular, elliptical, and W-weirs are …
Hydraulic jumps at drop and abrupt enlargement in rectangular channel
2002
The different types of hydraulic jumps that occur in a rectangular channel at an abrupt increase in section are experimentally studied. The abrupt section increase is due to both a drop and an increase in the channel width. Experiments were carried out with three different values of the ratio L/l between the channel widths respectively downstream and upstream of the abrupt section increase. For each L/l value five values of Froude number F1, of the supercritical flow upstream of the section increase were considered, and for each of them live values of the depth y1 of the same flow. The experiments showed that, as the depth y2 of the downstream subcritical flow increases, several types of hy…
Testing the outflow theory of Malcherek by slit weir data
2018
Abstract In this paper the flow-process of a slit weir is analyzed by the outflow theory of Malcherek. Average flow velocity over the slit weir is expressed in terms of head over weir and the momentum correction coefficient. The theoretically deduced stage-discharge formula was then calibrated using experimental data obtained for a ratio between the weir and the channel width ranging from 0.05 to 0.25. The deduced stage–discharge relationship allows to measure discharge values characterized by errors which are, for 91% of the measured values, less than or equal to ± 5%.
Effects of hydrological events on morphological evolution of a fluvial system
2018
Abstract This study quantifies morphological evolution of the Dez River, Iran, from 1955 to 2016. The approach uses a sequence of Landsat images, aerial photos, and topographic maps. In addition, the hydrological data including average daily discharge and yearly maximum discharge at the Dezful hydrological station for the period (1955–2016) were used. The study reach was divided into 48 meander loops from upstream to downstream. Active channel width (w) was determined at 10 m intervals and changes assessed along the study reach of the Dez River. Morphological indices including sinuosity index; straight meander length; centerline flow length; erosion area; erodible length channel migration; …