SIMULATION OF FLOW THROUGH A PUMP SUMP AND ITS VALIDATION
The efficiency and performance of pumping stations involving multiple pumping units depends not only on the efficiency of the pumping units but also on the proper design of the Intake sump. The proper design of pump intake is not an easy task because of the various site-specific geometrical and hydraulic constraints. The time and cost involved in sump model studies for design and optimization of sump geometry can be reduced to a large extent through CFD studies. However, writing a separate code for each new product is not feasible. Hence this work is aimed at determining the feasibility of commercial CFD software as a design optimization tool for pump sumps. In the present study commercially available software ANSYS CFX has been used for CFD analysis of flow conditions in a pump sump and the results obtained are found to be in good agreement with the experimentally observed flow patterns.
For the speed tracking control problem of the PMSM servo system,the saturation function is introduced to reduce the chattering phenomenon,one controller under uncertain environments is proposed.In the design of the controller,RBF network is used to approximate adaptively the uncertainty,while the backstepping method and the idea of sliding mode control are cited to design the controller.Theoretical analysis demonstrates that the controller can ensure the system Lyapunov stability.Numerical experiments show that the controlled system can effectively suppress uncertainty disturbance.The speed output can track the reference signal.