Three-dimensional numerical simulations are carried out by commercial software STAR-CCM+ to investigate the hydraulic transient and flow behaviours of a prototype pump-turbine during the normal shutdown process. The global characteristics and pressure fluctuations are analysed as the pump-turbine runs through the turbine mode, into the turbine braking mode, and finally into the reversed pump mo...

This paper deals with pump as turbine (PAT) as a feasible solution to the energy problems in rural and hilly areas. PAT provides an economical alternative to actual turbines especially for pico and microhydropower generation. PAT is essentially a pump operating in turbine mode by changing direction of flow and hence the direction of rotation of the impeller. In the forthcoming discussion, an in...

In this paper, performance of centrifugal pump as turbine (PAT) is investigated numerically. Three different specific speeds are considered and three pumps are designed using diagrams from catalogues and CFturbo V.9 software. Next, models are analyzed by Ansys CFX 16 software and results are compared with those of CFturbo software. Also, a mesh study analysis for one case is performed in order ...

This paper deals with the possibilities for the reduction of thermal environmental pollution and increases in the efficiency of the condensate system of a turbine by installing an inverter heat pump system. The inverter heat pump system will use the heat energy of the turbine exhaust steam that would otherwise be rejected. The operation of a condenser cooling system in a heating plant will be p...

Vertical turbine pumps are designed to operate with the pump shafts in tension (downthrust). Most pump and motor manufacturers caution users to not operate the vertical turbine pumps at conditions that result in “upthrust.” Upthrust conditions are usually encountered for a few seconds each time the pump is started; however, the pump should not be operated for periods longer than a few seconds i...

Due to the increasing share of new renewable energies like wind and solar in the generation of electricity the need for power regulation and energy storage is becoming of paramount importance. One of the systems to store huge amounts of energy is pumped storage using reversible hydropower units. The machines used in these power plants are pump-turbines, which can operate as a pump and as a turb...

Large centrifugal pumps can generate electricity in reverse, reducing the power supply pressure of grid. However, S region may occurs during operation and regulation pump as a steam turbine (PAT). The cause unstable unit startup, not only causing hydraulic system oscillation, but also accompanied by strong vibration noise. Understanding characteristic curve is great significance for improving s...