HYDRAULICS OF DOUBLE STILLING BASIN SYSTEMS
Practical application of broken-axis stilling basin systems can provide significant financial benefits. At this moment there is no generally accepted calculation method for their design. Based on physical model investigations an approximate theoretical model has been developed. This model makes it possible to describe the hydraulic phenomena proceeding in the double, broken-axis stilling basin systems. Main elements of the theoretical model: - 1st part of the upper basin, dimensioned on the basis of throwing distance of free jet. - 2nd part of the upper basin, calculated by impulse-momentum theorem. - 3rd part of the upper basin, the lateral weir, for whose calculation a new method has been developed. During the physical model investigation of the lateral weir it has been proved that for a suitable velocity distribution in the lower basin a relatively homogeneous discharge distribution is required along the lateral weir. This can be attained by a linearly changing height of the weir. No research is required in the lower basin if the influx from the weir has a uniform distribution. The practical applicability of the complex theoretical description adjusted to the different phenomena was checked by the results on the double stilling basin with axis broken by 90°. This comparison has proved the practical applicability of the theoretical formulas.