BY RAINFALL AND SOFTWARE CALCULATION OF HIGH WAVES GENERATION IN A CATCHMENT BASIN AND THEIR PASSING THROUGH DAMS

摘要

The balance high-wave modeling was developed on the basis of observations of the annual maximum of daily rainfall. This is necessary, because by means of rainfall the high waves are from 2 to 20 times bigger than the Q_(max) calculated on the basis of the observed max flow. Thesuggested solution is considered for different duration of rainfall, namely 24 h, 12 h, 6 h and min hours. The min rainfall duration is equal to the time it takes the flood to the catchment basin to pass from the watershed into the river. For that purpose, the rainfall in mm is established as standard probability. Then, the flood to the basin and the drainage into the river next to the dam, are calculated for different rainfall duration. Then, by means of Balanced Modeling, the shape and the diagram of the high wave with branches of upsurge, detention and subsiding are established. Finally, the regulation and the retention of the high wave in the dam are found. For the above mentioned cases, algorithms and software applications for the individual stages operate in four different modes in order to establish: the rainfall for theoretical curve selection; the flood and drainage with single or double iteration; the shape and diagram by mans of Balanced Modeling; the alternative investigation of the regulation and the retention in connection with the relieving structures (overflow, discharge pipes) and the volumes under and over the overflow crown.With the help of numerical method of finite strips, irrespective of the complexity in the topography and the hydraulic conditions in the catchment basin, the latter is divided into longitudinal and cross strips. By means of the dynamic equation of motion, of the hydraulic losses and continuity, the transition processes of flood and drainage in the basin are solved. According to the soil characteristics of the catchment basin and the water saturation, the settlements and agriculture in the upper and the lower section of the dam, the new method can lead to a rational and safe solution of the project concerning high wave and respectively Q_(max).With calculations of the time for flood and drainage into the dam carried out by pluviometer, level indicator and automation, the preliminary time required for partial emptying, fill, open, or shut through the discharge pipes and radial gates can be forecasted.