The piano key weir (PKW) is a type of nonlinear control structure that can be used to increase unit discharge over linear overflow weir geometries, particularly when the weir footprint area is restricted To predict the outflow passing over a piano key weir, the discharge coefficient in the general equation of weir needs to be known. This paper presents the results of laboratory model testing of...

side weirs are flow diversion devices that are widely used in irrigation, drainage and urban sewage systems. the present study focuses on the investigation of the effect of oblique side weirs on the discharge coefficient of a side weir under subcritical flow condition in rectangular channels. in this study 106 laboratory tests were conducted and the results were analyzed to find out the influen...

side weir is a flow control structure that used extensively in irrigation and drainage as well as sewer networks. throughout the present research, a study comprised of 162 experiments was done on sharp-crested semi-circular side weir. since the height in this side weir varies along its length, this feature enables it to more properly control flood than rectangular side weirs in various flood co...

UNLABELLED The limit of the Colletotrichum gloeosporioides species complex is defined genetically, based on a strongly supported clade within the Colletotrichum ITS gene tree. All taxa accepted within this clade are morphologically more or less typical of the broadly defined C. gloeosporioides, as it has been applied in the literature for the past 50 years. We accept 22 species plus one subspec...

weirs have widely been used for the flow measurement, flow diversion and its control in the open channels. attempts have been made to study flow over different shapes of normal weirs, side weirs and oblique weirs. this paper is connected with the development of the discharge coefficient measurement. in the present study four different weirs in different height are considered for validation purp...

Different construction materials with different roughness used to make circular weirs highly affect surface roughness and, in turn, flow hydraulics passing over these structures.  In the present research, numerous experiments under different hydraulic conditions were performed on a physical model to study the effects of roughness on flow hydraulics over a circular weir. The flow hydraulics incl...

Scour in bed material downstream weirs is considered the most unfavorable process which threats the overall stability of the weir. Weirs with oblique angle in the horizontal plan will affect the scour profile downstream the structure and may reduce it. The objective of this paper is to investigate the effect of oblique weir angle on the scour profile. Furthermore, the effect of V-notch angle on...

Orifice-weir structures at ditch outlets are proposed to reduce peak drainage rates during high flows and to store water during the growing season in poorly drained managed pine plantations. Two coastal watersheds, one conventionally drained (D1) and another with an orifice-weir outlet (D3), were monitored to examine the effects of this orifice treatment on drainage outflows and nutrient export...

Side weirs are used in open channels to control flood and the flow passing through it. Discharge capacity is one of the crucial hydraulic parameters of side weirs. The aim of this study is to determine the effect of the intended dimensionless parameters on predicting the discharge coefficient of triangular labyrinth side weir. MAPE, RMSE, and R2 statistic indexes have been used to assess the ac...