The influence of changing hydropower potential on performance parameters of pump in turbine mode
Czech University of Life Sciences in Prague, Faculty of Engineering, Kamýcká 129, CZ16521 Praha 6, Czech Republic
Various types of hydromotors that enable energy recovery simultaneously with the required pressure reduction can be used in the field of fluid pumping systems. Similar principle is applied, for example, in the case of use of hydrodynamic pumps in turbine mode (PAT), which are also used as an alternative to conventional turbines in small hydropower plants. However, these pumps do not usually have the possibility of regulating hydraulic parameters, as it is common with conventional turbines. This specific feature needs to be taken into account, when designing such system. Article analyses computational methods for the conversion of the performance characteristics and compares these results with experimentally measured data on a particular pump in turbine mode. The results indicated that conversion can be well used in practice to predict outputs as well as to determine the optimum total head and flowrate to ensure maximum efficiency of PAT operation. Further computations were influenced by deviations resulting from the change in efficiency during PAT operation.