INVESTIGATION PERFORMANCE OF PICO HYDRO WATER PIPE TURBINE

The flow of water in the pipeline for household needs is a source of energy that can generate electrical energy through Pico hydro turbines or small-power water turbines. The experiment has been conducted on a 10 Watt Pico hydro turbine mounted on a water pipe against changes in water flow discharge. The turbine performance analysis is conducted experimentally (actual) and theoretically (ideal). The analysis results showed the greater the discharge flow, the greater the power generated by the turbine. In tests with a maximum discharge of 8.9 l/min, the actual power of 1.121 Watts, the torque of 0.005 Nm with a rotation speed of 2146.8 rpm and efficiency of 12.59%; while the ideal power is based on Euler turbine equation of 4.2 Watts and torque of 0.016 Nm. So, the maximum turbine power that can be generated is only 26.67% ideal. Efficiency turbine decreases with increased discharge; in this test, the maximum efficiency was 24.89% at 5.8 L/min flow discharge.

Experimental study of the Effect of the Blades of Number on Characteristics Pico Bulb Turbine on Horizontal Flow

This study discusses the effect of the number of blades on a horizontal flow propeller turbine performance on a small scale experimentally. The development of small-scale water turbines has made many advances, including water turbines with the horizontal flow. Water turbines in horizontal flow can be applied to irrigation systems, piping systems, the wastewater treatment channel, and other closed channels. Pengukuran dynamic head pada aliran horisontal berdasarkan nilai pressure drop atau perbedaan tekanan sebelum dan sesudah turbin. Dynamic head measurement on the horizontal flow is based on pressure drop values or pressure before and after the turbine. Static bulbs placed before the turbine aim to increase the speed of water flow and potentially improve turbine performance. This study aims to determine the effect of the number of blades on the performance and efficiency of propeller turbines. The blade angle used is 200 with a bulb ratio of 0.6 to the pipe diameter. The variations in the number of blades used were 4, 5, 6, and 7, with each tested at 7 L / s, 9 L / s, 11 L / s, and 13 L / s. The results of this study indicate the number of blades 5 with a discharge of 13 L / s shows the best turbine performance compared to the number of other blades, besides that the number of blades 5 with a flow rate of 13 L / s shows the best efficiency value of around 40%.

Optimization of the Efficiency of a Michell–Banki Turbine Through the Variation of Its Geometrical Parameters Using a PSO Algorith

Small-scale hydropower generation can satisfy the needs of communities located near natural sources of flowing water. The operating conditions of a Michell–Banki Turbine (MBT) are relatively easier to meet than those of other types of turbine, making it useful in places where other devices are not suitable. Moreover, MBT efficiency is almost invariable with respect to flow rate conditions. Nevertheless, such efficiency commonly ranges between 70% and 85%, which is lower than that of other water turbines like Turgo, Pelton, or Francis turbine. The objective of this work is to determine the maximum theoretical efficiency of an MBT and its associated geometrical parameters by implementing Particle Swarm Optimization. The results show a higher effectiveness of the mathematical formulation compared with other cases from literature and show the performance of the optimization method proposed in this study in terms of solution and processing time. Finally, a maximum MBT efficiency of 93.3% was achieved

Theoretical demonstration of a capacitive rotor for generation of alternating current from mechanical motion

Innovative concepts and materials are enabling energy harvesters for slower motion, particularly for personal wearables or portable small-scale applications, hence contributing to a future sustainable economy. Here we propose a principle for a capacitive rotor device and analyze its operation. This device is based on a rotor containing many capacitors in parallel. The rotation of the rotor causes periodic capacitance changes and, when connected to a reservoir-of-charge capacitor, induces alternating current. The properties of this device depend on the lubricating liquid situated between the capacitor’s electrodes, be it a highly polar liquid, organic electrolyte, or ionic liquid – we consider all these scenarios. An advantage of the capacitive rotor is its scalability. Such a lightweight device, weighing tens of grams, can be implemented in a shoe sole, generating a significant power output of the order of Watts. Scaled up, such systems can be used in portable wind or water turbines.

Analysis of numerical instability of centrifugal pumps operational characteristics

In recent years, computational fluid dynamics has been increasingly used in the development of various types of rotating machines. In the case of water turbines and pumps, a large number of researches have been published recently, related to the use of different numerical methods for prediction of efficiency, cavitation characteristics and different dynamic phenomena. For basic analysis an accurate result near the optimal operating regime is sufficient, but for detailed analysis the numerical analyses in the wider field of operating conditions are necessary. Thus, we encounter some otherwise known physical phenomena that occur in the part load and full load regime. In these areas, due to the nature of the flow, various non-stationary phenomena occur that are dominant for such operating regimes. In this paper, the problems that arises if we consider only stationary results and some recommendations to avoid later problems in the operation of centrifugal pumps are presented.

Persistent monochromatic seismic signals across central Europe: AlpArray data indicate a man-made seismic source for regional wave propagation studies

<p>Consistent and monochromatic signals appear as sharp peaks in frequency spectra or as continuous lines in spectrograms on many permanent and temporary seismic stations in Central Europe, especially in South-Eastern Germany, Austria and the Czech Republic. Similar observations have already puzzled the seismic community more than 20 years ago. Here we report on new observations of such monochromatic seismic signals within a 1 – 10 Hz range across central Europe using the dense AlpArray network.</p><p>We identify several monochromatic signals on both permanent and temporary stations. The respective frequencies of e.g. 1.72 Hz, 2.08 Hz, 2.77 Hz or 4.16 Hz are generally stable even over long time spans (months to years). Strikingly, all such signals at any given station show identical and simultaneous short-term (minutes to days) frequency variations of up to 0.4% of the central frequency. These variations precisely correspond to fluctuations of the frequency of the European electric power network, which is regulated to 50 Hz +/- 0.4%. In fact, all persistent seismic signals that follow this behavior have frequencies of 50 Hz / n with n being an integer number (50 Hz / 29 = 1.72 Hz, 50 Hz / 24 = 2.08 Hz, 50 Hz / 18 = 2.77 Hz, 50 Hz / 12 = 4.16 Hz). We show that if the frequency of an observed spectral line is an integer fraction of the power network frequency (and only in that case) it will perfectly follow the fluctuations of the power network. This obviously raises questions about the nature of the signal itself, in particular if it is of seismic or maybe electro-magnetic origin.</p><p>We confirm that the signals are of seismic origin and we have identified water turbines inside river power plants as the source. The observed frequencies correspond well to reported rotation frequencies of water turbines at several different river power plants in Southern Germany and Austria. The seismic signals may propagate to almost 100 km from the corresponding plant. We analyze the spatial distribution of signal amplitudes for a selected river power plant in Austria, and show that it is similar to expected isolines of seismic shaking for an earthquake in the region.</p><p>Knowing the source of those exotic signals potentially enables us to use them for seismo-tectonic purposes. The long-term (several years) stability and the permanent availability (24h operation of water turbines) render them very interesting sources e.g. for studying temporal seismic velocity variations in the shallow crust.</p>

Investigation of the Capacity Factor of Weather-Routed Energy Ships Deployed in the Near-Shore

The energy ship concept has been proposed as an alternative wind power conversion system to harvest offshore wind energy. Energy ships are ships propelled by the wind and which generate electricity by means of water turbines attached underneath their hull, The generated electricity is stored on-board (batteries, hydrogen, etc.) It has been shown that energy ships deployed far-offshore in the North Atlantic Ocean may achieve capacity factors over 80% using weather-routing. The present paper complements this research by investigating the capacity factors of energy ships harvesting wind power in the near-shore. Two case studies are considered: the French islands of Saint-Pierre et-Miquelon, near Canada, and Ile de Sein, near metropolitan France. The methodology is as follows. First, the design of the energy ship considered in this study is presented. It was developed using an in-house Velocity, and Power Performance Program (VPPP) developed at LHEEA. The velocity and power production polar plots of the ship were used as input to a modified version of the weather-routing software QtVlm. This software was then used for capacity factor optimization using 10m altitude wind data analysis which was extracted from the ERA-Interim dataset provided by the European Centre for Medium-Range Weather Forecasts (ECMWF). Three years (2015, 2016, and 2017) data are considered. The results show that average capacity factors of approximately 40% and 40% can be achieved at Ile de Sein and Saint-Pierre-et-Miquelon with considered energy ship design.