Energy crisis and high emission of fossil fuels are major driving forces for developing renewable energy based technologies. In order to meet growing demand for energy, hydropower can be one of the sustainable alternatives. Further, the hydrokinetic turbine is considered as one of the most emerging technologies which harness energy from flowing water. In this paper, an attempt has been made to review hydrokinetic energy theory for energy conversion system from water currents analogous to wind power system. The most widespread classes of hydrokinetic turbines are discussed in detail with respect to their benefits, drawbacks and desirable conditions for applications. It has been found that in spite of some prevailing downsides of vertical axis turbine like of self-starting and lower efficiency, vertical axis turbines are appealing for many riverine applications. One of the prominent turbines of its kind is the Savonius hydrokinetic turbine that has the capacity to self-start at a very low fluid velocity in the river, canal etc. However, Savonius type hydrokinetic turbine inherently has poor efficiency. A number of experimental and numerical studies with a large number of physical designs and parameters have been carried out in the area of Savonius rotor to enhance its efficiency. Under this study, review of different parameters affecting the performance of Savonius hydrokinetic turbine has been carried out and presented in this paper which may be useful for future studies to improve the efficiency of such turbines.

Performance parameters of Savonius type hydrokinetic turbine – A Review

Harvesting wind energy for improving performance of Savonius rotor

CFD study of Savonius wind turbine: 3D model validation and parametric analysis

Performance study of ducted nozzle Savonius water turbine, comparison with conventional Savonius turbine

Parametric analysis of model Savonius hydrokinetic turbines through experimental and computational investigations

For solving the world energy problem and the bad effect of conventional sources of energy on environment, great attention allover the world is paid towards the use of renewable energy sources. Special interest is paid towards wind energy because of its competitively.

Savonius rotor is a vertical axis wind turbine which is characterized as cheaper, simpler in construction and low speed turbine. This makes it suitable for generating mechanical energy in many countries especially in Egypt.

In this work different geometries of Savonius wind turbine are experimentally studied in order to determine the most effective operation parameters. It was found that, the two blades rotor is more efficient than three and four ones. The rotor with end plates gives higher efficiency than those of without end plates. Double stage rotors have higher performance compared to single stage rotors. The rotors without overlap ratio (β) are better in operation than those with overlap. The results show also that the power coefficient increases with rising the aspect ratio (α). The conclusions from the measurements of the static torque for each rotor at different wind speeds verify the above summarized results of this work.

An experimental study on improvement of savonius rotor performance

Savonius turbine is a vertical axis wind turbine (VAWT) which is suitable to operate at low wind velocities. The experimental investigation to improve its performance is a big challenge as; it is expensive, complicating and time consuming. Numerical prediction using CFD simulation could be a valuable alternative. This paper introduces a new modification of Savonius wind rotors to improve its performance. The proposed modification consists of a curtain arrangement together with fin addition on blade. The effect of the proposed modification was predicted using a CFD simulation employing ‘ANSYS FLUENT 16′. The curtain arrangement was located in front of the rotor to avoid the opposing torque to the rotor rotation. The fins were added to exploit the space in the blade for guiding the wind flow. The performance of the rotor with different curtain arrangements and variable number of fins was predicted and assessed against that of the conventional rotor. This comparison aimed to optimize the geometrical data of the proposed curtain arrangement with the number of added fins. The maximum power coefficient of the Savonius wind rotor was found to be increased to about 42 % with the optimum curtain arrangement (lengths of the curtain blades 1000 and 1150 mm and the angles of the curtain blades 30 and 50) together with adding only one fin. The simulation results showed that the performance of Savonius wind rotors could be significantly enhanced with a proper selection of curtain arrangement and number of fins to be added on the blade. 

Numerical prediction of improvement of a Savonius rotor performance with curtaining and fin addition on blade

In this work, it is planned to design and test a prototype of Savonius rotor in free wind based on the results of the previous experimental study. The prototype is designed and tested in El-Arish at the Faculty of Engineering, Sinai University. Although El-Arish has lower average yearly wind speed compared to other locations with higher average wind speed, like Hurghada. The results show that Savonius rotor prototype in El-Arish gives considerable efficiency and begins to give power at a relative low wind speed. While the energy generated from the Savonius rotor prototype in El-Arish is small, the cost of energy generated is competitive with other energy sources. The cost of kW hr generated from Savonius rotor is expected to be very low specially in locations with high average wind speed. The majority of the Egyptian locations having an average wind speed between 3.5 and 4.5 m/s. The cost of kW.hr generated from Savonius rotor in these locations is expected to be between 0.42 and 0.28 LE. In locations where average wind speed is 6 m/s, the cost of kW hr is expected to be 0.1 LE. Therefore the use of Savonius rotor will be attractive in many locations in Egypt and it can be used to pump water for irrigation of lands. This will save a great part of conventional energy sources used for this purpose and consequently reduces the environmental pollution. بط ُّيبرٕج تب زنط عنُ منًلج بناضأ يُنصحنا ةهٓطٔ ًٍثنا ةصيخر بَٓأب شيًحج ٗحنا ةيطأزنا تبُيبرٕحنا ٍي ْٗ ّيئإٓنا صٕيَٕف ّافخُي ءإْ , زصي بُٓئ ّييبُنا لٔعنا ٗف بٓياعخحطا ٍكًض ٗحنا ّيئإٓنا تبُيبرٕحنا مافا ٍي بٓهلجض كنذ . زحن ٗننٔأ وذٕنًَ ربناحخخٔ يُنصجٔ ىيًصج ىج مًلنا اذْ ٗف تبنطبي نا تئبنحَ ٗنه اعنًحلي زنتنا ءإنٓنا ٗنف ةنيئإٓنا صٕيَٕفبنط ةنُيب ةنيهكب مةنيكيَبكيًنا ٖٕن نا ةنطعُْ ىنظ ب موعن حًنا نئإًنا بنكيَبكيي منًلي ٗنف صٕيَٕفبط ةُيبزج ٍي وذبًَ ٗه ثضزجأ ٗحنا ةيهًلًنا ةيفًُٕنا ةليبج مةطعُٓنا . شضزلنا ةُضعي ٗف ٗنٔلأا وذًُٕنا رباحخخٔ يُصج ىج ءبُيط ةليبج مةطعُٓنا ةيهكب . شضزنلنا ٌأ ٍني ىأزنبنب اذنْ مةنافخُي نبنضر تب زنط عنُ ةقبط عينٕج ٗف أعاضٔ مةنٕ لي ةءبفكب مًلض ٗنٔلأا وذًُٕنا ٌا عجٔ ع نٔ ةافخًُنا نبضزنا تب زط تاذ ةضزصًنا قطبًُنا ٍي زاحلج . ٕحًنا ةنقبطنا ٍني منقا زاحلج صٕيَٕفبط ةُيبزج ٍي ةعنٕحًنا ةقبطنا ةءبنف ٌلأ كننذٔ ةنينبلنا تب زنظنا تاذ ةني فلأا تبنُيبزحنا ٍني ةعنن ةنقبطهن ٖزنخلأا رلبنصًنا ضفبنُجٔ ةنافخُي زناحلج صٕيَٕفبنط ةنُيبزج ٍني ةنجحًُنا ةنقبطنا ةعحٔ ةفهكج ٍكنٔ ممقأ صٕيَٕفبط ةُيبزج ةُيبزحنا ِذْ ءبشَلإ ةافخًُنا ةفهكحنا باظب كنذٔ . نُي ىظلي ٗف ةططٕحًنا نبضزنا ة زط ٌخ ٍينب ن ج زنصي قطب 3.54.5 m/s ٔ م دق ل ةنفهكج ٌأ عنجٔ kW hr ةنُيبزج ٍني تحنًُنا ٍيب حط زصي قطبُي ىظلي ٗف صٕيَٕفبط 0.42-0.28 LE ٗننخ منصحن ةنفهكحنا من ج إنط بنًُيب ماعنج ةننٕ لي ةنفهكج ٗنْٔ LE 0.1 ةططٕحًنا نبضزنا ة زط بٓب ٗحنا قطبًُنا ٗف m/s 6 . يبزج واعخحطخ ٌإف كنذنٔ ةزنيث قطبنُي ٗنف ةنقبطنا عينٕحن صٕيَٕفبط ةُ ةزنيا ةنيًْأ ّنن ٌٕكينط زنصي ٗنف . ٗن ارلأا ٖزنن ةنيس ا ِبنيًنا رنان تبناًهطنا ةرالخ ٗنف ةنُيبزحنا ِذنْ واعخحنطخ ٍنكًًنا ٍنئ ا ٍني بناضأ منه ض إنطٔ متباًهطنا ِذْ ةرالخ ٗف وعخحظًنا ٖعيه حنا لٕقٕنا ٍي ةنٕ لي تبيً زفٕض إط اذْ مةي ارشنا تبنثبلاَلإ ٗئيانا خٕهحهن ةااظًنا ةضرازتنا .

https://erjm.journals.ekb.eg/article_67254_c49030bb68ca397027e04c58563b2e40.pdf

A. A. El-Haroun

Papers

An experimental study on improvement of savonius rotor performance

Numerical prediction of improvement of a Savonius rotor performance with curtaining and fin addition on blade

Savonius rotor prototype based on wind tunnel testing