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Francis Turbines are designed to Extract hydraulic power as much as possible in hydro power plant stations. Performance analysis and selecting design of hydraulic turbines are two very essential aspects of any hydro power project which ensure the economical and efficient functioning of these hydro power plants.CFD simulation can provide us insight into field flow characteristics which will help us understand the design parameter and development of Francis turbine. The performance analyzed in different operating conditions with the help of numerical simulation and experimental testing. The various visualization techniques in numerically and Physically model testing for hydraulic performance with maximum-minimum and rated head and different flow rate analyses of the turbines are briefly discussed. These techniques can be provided efficiency and insight flow characteristics with different operating conditions of the Francis turbine. Efficiency is calculated 94% with Computational fluid dynamics simulation with an error of less than 0.7% compared with physical model testing. The numerically simulation and physical model testing are shown that feasibility for the optimal design of the hydraulic Francis turbine.

Thrust bearing is a key component of hydroelectric generator and bears the axial load of the unit. During transient processes, such as start and stop of the unit, thrust bearing usually occurs wear phenomenon at pad surface, which affects the stable operation of the unit and reduces service life of the bearing. Based on two-way fluid-solid-thermal interaction, this paper did transient thermal-elastic-hydrodynamic (TEHD) analysis of a tilting pad thrust bearing under the pump mode. For the fluid region, the Reynolds equation and the viscosity-temperature equation are solved. For the solid region, transient heat conduction equation and basic thermal-elasticity equation are considered. The data transferred in the fluid-solid interface satisfy the fluid-solid-thermal interaction equation. The variation of the lubricant oil temperature, the oil film force, the pad surface inclination angle and axial velocity of pad and mirror plate are analysed, which provide theoretical basis for the design of bearing and the safe operation of the unit.

In traditional path planning methods based on Deep Q-Network (DQN) algorithm for mobile robots, the target Q value was usually obtained by a greedy algorithm, and the estimation of Q value was usually high, which would result in slow training speed of the algorithm. To solve this problem, a Dueling DQN algorithm based on Dueling network was proposed in this paper, which was mainly realized by the structure optimization of neural network. The initial algorithm structure was divided into two states and a higher return is obtained through competitive comparison. Then, the long training time and slow speed convergence problem could be effectively solved than the traditional DQN. The simulation results show that the DQN algorithm based on Dueling DQN has high efficiency in Q value obtaining. Compared with the traditional DQN method, it has the better anti-interference ability and decision-making ability, less training time, and stable convergence.

The bidirectional thrust bearings are used to balance the thrust load of the entire shaft system which play an important role in the pumped storage units. The lubrication is usually analyzed by simultaneously solving the Reynolds equation, energy equation, film thickness equation of the film and the heat conduction equation, elastic equilibrium equation of the pad. However, in this method the assumptions for the inlet temperature of the film and the wall heat coefficients on the pad greatly affect the numerical accuracy. This study used fluid-solid-thermal interaction method, built three dimensional (3D) FEM model for the pad and collar and the 3D CFD model for the oil film, and then analyzed the influence of the thrust loads and the Babbitt layer on the bearing performance. The results show that increasing the thrust load will rapidly decrease the minimum film thickness, increase the maximum pressure and maximum temperature on the pad. Increasing the thickness of the Babbitt layer on the pad sliding surface will increase the minimum thickness of the film, decrease the maximum temperature on the pad which improve the bearing lubrication.