Enhancing the Efficiency of Small-Scale and Microhydroturbines Using Nature-Imitation Technologies for the Development of Autonomous Energy Sources

Abstract

The issues of developing small-scale and microhydropower generation under present-day conditions as one of the renewable energy sources that do not aggravate environmental problems are considered. Some of the most effective approaches to designing microhydropower plants and small-scale and microhydroturbines that meet the environmental friendliness and high-energy efficiency requirements are outlined. The results of a computational study of a microturbine prototype with a blade system modified according to a principle of biomimetics (nature-imitation technologies) have been validated experimentally. Two modified configurations of the blade system are considered and compared with the original version under identical conditions. To increase the reliability of the findings, the experiment with the original and modified impellers of the microhydroturbine was repeatedly conducted. The energy characteristics of a microhydroturbine based on experimental data that demonstrate the best repeatability with an error not exceeding 10% are presented. Based on the calculated and experimental data, a comparative assessment of the turbine’s energy characteristics with the original and modified impellers is made. It has been established that the use of the so-called “growths” on the entrance edge of the impeller blades contributes to streamlining the flow pattern in the interblade channel. This, in turn, leads to a decrease in hydraulic drag and, consequently, to a decrease in hydraulic losses when flowing around the blade system. As shown by quantitative assessment of the energy characteristics, the energy efficiency of a microhydroturbine is increased by 20%, which proves the viability of the chosen direction for developing smallscale and microhydropower generation as well as the effectiveness of the approaches used in the design of the working bodies of microhydroturbines. Further ways of improving the approaches under study and obtaining new developments in this field of hydropower generation are scheduled and set forth.