Applied Mechanics and Materials Vols. 353-356

Abstract: Using numerical simulation method for project simulating prediction, the built mathematical models of actual conditions often need to be generalized, consequently, there are some inevitably deviations between model prediction results and the measured data, which requires the adjustment of model parameters to improve the model. This paper made a comparative analysis of Shifosi reservoir impoundment test observation water levels and model prediction water levels, adjust the model parameters and boundary conditions, then it would get the sensitive parameters that affect the accuracy and stability of numerical model and boundary condition and improve the fitting degree of measured data and simulation results.

Abstract: Due to the quests of technology and changes of external load, dynamical system would under non-regulative operating condition. To discuss this situation, this paper did some research about the unsteady flows in centrifugal pump by simulating test. It shows that if non-regulative operating condition emerges in the pump system, some unsteady flow which possesses transient characteristics would appear, which driven by the common disturbance from the pump and valves in this system. Besides, the transient intensity of the system under non-regulative operating condition depends on the relative intensity of the capacity and inertia. When the capacity in system dominates, it would make transient intensity weaken, but if the inertia dominates, the transient intensity would move to an opposite side.

Abstract: By fully collected and surveyed on the soil landslide, with the help of generalized model, the experiment simulated the landslide occurrence and exchange process of soil landslide entered the water. Through the calculation and analysis of test results and influencing factors, it is given out the height of the initial surge, variation of the progressive surge and empirical formula of soil-landslide surge. Compared with experimental data, it is found that empirical formula has certain accuracy and it can provide a certain reference on surge disaster forecast.

Abstract: In order to research the siltation problem of pressurized CSO chamber with the outlet pipe elevation higher than that of the inlet pipe, a 1:5 scale model was made of plexiglass for laboratory experiments. The velocity field of the CSO chamber was measured by PIV system. VOF and DPM models were adopted in the numerical simulation, and the results were applied to the comparison and analysis with the field inspection images obtained by SONAR system. Research results show that this special CSO chamber is liable to result in siltation in dry weather flow. The deposit location and shape of sediment depend on the flow field distribution. At low flow, there is low velocity eddy zone at the central region of CSO chamber, and then there is a bulge in the middle of sediment contour line in horizontal plane. With the increase of flow, the scouring force of middle region enhances, and then the sediment contour line tends to a straight line. Furthermore, there are relatively strong scour areas at both sides of inflow which result in the trend to be flat of sediment surface. These analyses are validated by field inspection of SONAR.

Abstract: The flow characteristics of fish-bone type dividing dike is very complicated. By model experiment, this paper deeply research in water surface line, velocity distribution and the flow regime of fish-bone type dividing dike. It can Provided the certain basis for the design of fish-bone type dividing dike, such as a fishbone in dam engineering stab dam ridge direction, length, and layout spacing, length.

Abstract: Using pressure diagram to analyze the pressure distribution of distributed power system when the zero-pressure-difference point is in different positions. Conclusions can be drawn as follows: the zero-pressure-difference point should be between the critical point and heat source to eliminate the energy consumption of regulators. And as a result the transmission energy consumption of the system becomes lowest. When the zero-pressure-difference point is in different positions between the critical point and heat source, arrangements of pumps of the system are different. But the total output power of the pumps is the same. The zero-pressure-difference point and the schemes for pump head can be conveniently determined by graphical method like pressure diagram or numerical method.

Abstract: Songzikou has the greatest diversion ratio among the three outlets at Jingjiang River. The water and sediment diversion ratios are changed after water storage of the Three Gorges Reservoir. The changing trends are critical for the evolution of the river-lake relationship. According to the water and sediment diversion data obtained from 2003 to 2010 in the Songzikou, it could be found that the water diversion ratios in the Songzikou under different Zhicheng flow are enhanced and its sediment diversion ratios also had an increasing trend after the Three Gorges Reservoir storage. The variations were mainly related to the water levels of main streams, the change of river regime and the diversion angle near the outlet. In addition, the changes were also associated with the evolution characteristics of outlet channel. We further studied how flood regulation of the Three Gorges Reservoir influenced the diversions of the Songzikou.

Abstract: In order to study the applicability of SWAT model in small and medium-sized basin, the author established SWAT model to simulate monthly runoff in Wohushan Reservoir basin. According to a lot of basic data, the spatial database and the attribute database were constructed. The entire study area was divided into 51 catchments including 126 hydrological response units. The parameters were validated by the measured data from 2007 to 2009 and calibrated from 2010 to 2011. The correlation coefficient and the Nash efficiency coefficient of monthly runoff simulation are higher than 0.70, and the relative error is lower than 15%. Considering some potential errors between the measured data and the simulated data, SWAT model can simulate the runoff process of Wohushan Reservoir basin well.

Abstract: Flood control dispatching of reservoir belongs to the ex-ante decision. This paper established the flood pre-discharge dispatching multi-objective risk index system and fuzzy optimization model method, taking Long Men reservoir as an example, to study the design flood pre-discharge scheme for different frequency, different frequency analysis of design flood pre-discharge flow and pre-discharge time, provide the reservoir flood pre-discharge scheme of different frequency flood and provide reliable basis for reservoir flood control pre-discharge dispatching.

Abstract: Studying the important effects of sediments on the seismic response of dams ,This paper established the calculation model based on regarding the water reservoir as compressible fluid ,the dam and the foundation as an elastic solid, the sediment as Liquid-Solid two-phase porous medium. The results showed that the sediment thickness and properties have important effects on the dam seismic. Increasing the thickness of sediment ,the seismic response of acceleration significantly decreased, the hydrodynamic pressure significantly reduced , which is benefited to the safety of the dam.