Page - 184 - in Book of Full Papers - Symposium Hydro Engineering

Figure 1 the plan of the experimental model of vortex settling basin To determine the basin inlet discharge, the discharges of two downstream channels were calculated by measuring their water surface figures using a point Gauge. At the end of these canals, there were two calibrated weirs. The outlet channel weir of the vortex settling basin weir was rectangular and the outlet channel weir of the settling basin was triangular with an angle of 90 degrees. 2.2. Sediment Injection In experimental models, sediments were injected in such a way that there was the necessary matching between the model and the actual sample. Therefore, the material collected from various parts at the end of the experiments must be equal to the amount of the injected upstream. Moreover, the sediment load should be poured in a suitable place so that it has the opportunity to have a uniform distribution in the flow cross section, and also sediments are entered into the basin in a suspended manner. In their studies, researchers used different grains, some of which are shown in Table 1. Different materials were examined to determine the type of settled material and finally, given issues such as sediment supply, grain size, injection, sampling, collection, drying, density and uniform distribution, sand drift was used. Sediments are made of sand drift with a grain size of d50=0.22 mm. 184