Optimum Design of the Darrieus-Type Cross Flow Water Turbine for Low Head Water Power

The purpose of this investigation is to research and develop a new type water turbine, which is appropriate for low-head open channel, in order to effectively utilize the unexploited hydropower energy of small river or agricultural waterway. The application of placing cross-flow runner into open channel as an undershot water turbine has been under consideration. As a result, a significant simplification was realized by removing the casings. However, flow field in the undershot cross-flow water turbine are complex movements with free surface. This means that the water depth around the runner changes with the variation in the rotation speed, and the flow field itself is complex and changing with time. Thus it is necessary to make clear the flow field around the water turbine with free surface, in order to improve the performance of this type turbine. In this research, the performance of the developed water turbine was determined and the flow field was visualized using particle image velocimetry (PIV) technique. The experimental results show that, the water depth between the outer and inner circumferences of the runner decreases as the rotation speed increases. In addition, the fixed-point velocities with different angles at the inlet and outlet regions of the first and second stages were extracted.

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Study on an Undershot Cross-Flow Water Turbine with Straight Blades

International Journal of Rotating Machinery ◽

10.1155/2015/817926 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 4

Author(s):

Yasuyuki Nishi ◽

Terumi Inagaki ◽

Yanrong Li ◽

Kentaro Hatano

Keyword(s):

Flow Field ◽

Output Power ◽

Cross Flow ◽

Open Channels ◽

Small Scale ◽

Hydroelectric Power ◽

Turbine Efficiency ◽

Water Turbine ◽

Low Head ◽

Hydroelectric Power Generation

Small-scale hydroelectric power generation has recently attracted considerable attention. The authors previously proposed an undershot cross-flow water turbine with a very low head suitable for application to open channels. The water turbine was of a cross-flow type and could be used in open channels with the undershot method, remarkably simplifying its design by eliminating guide vanes and the casing. The water turbine was fitted with curved blades (such as the runners of a typical cross-flow water turbine) installed in tube channels. However, there was ambiguity as to how the blades’ shape influenced the turbine’s performance and flow field. To resolve this issue, the present study applies straight blades to an undershot cross-flow water turbine and examines the performance and flow field via experiments and numerical analyses. Results reveal that the output power and the turbine efficiency of the Straight Blades runner were greater than those of the Curved Blades runner regardless of the rotational speed. Compared with the Curved Blades runner, the output power and the turbine efficiency of the Straight Blades runner were improved by about 31.7% and about 67.1%, respectively.

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AERODYNAMIC MODELS APPROXIMATE FOR ESTIMATING THE BLADE PERFORMANCE OF A DARRIEUS-TYPE CROSS-FLOW WATER TURBINE

International Journal of Fluid Mechanics Research ◽

10.1615/interjfluidmechres.2019027180 ◽

2020 ◽

Vol 47 (1) ◽

pp. 85-98

Author(s):

Fatima Meddane ◽

Tayeb Yahiaoui ◽

Omar Imine ◽

Lahouari Adjlout

Keyword(s):

Cross Flow ◽

Water Turbine

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Improvement of Torque Performance of a Vertical Axis Type Marine Turbine for a Water Current Generation System

29th International Conference on Ocean, Offshore and Arctic Engineering: Volume 3 ◽

10.1115/omae2010-20474 ◽

2010 ◽

Author(s):

Tomoki Ikoma ◽

Shintaro Fujio ◽

Koichi Masuda ◽

Chang-Kyu Rheem ◽

Hisaaki Maeda

Keyword(s):

Turbine Blades ◽

Angle Of Attack ◽

Cross Flow ◽

Vertical Axis ◽

Hydrodynamic Forces ◽

Water Current ◽

Current Channel ◽

Marine Current ◽

Water Turbine ◽

Type Water

This paper describes the possibility of an improvement of torque performance and hydrodynamic forces on a vertical axis type water turbine, used for marine current generating system. The water turbine analyzed here is based on a Darrieus turbine with vertical blades. We considered possibilities of controlling the angle of attack of blades in order to improve the starting performance and to reduce energy loss during the rotation of the turbine. We used blade-element/ momentum theory in order to investigate the variations appearing in torque performance when the angle of attack were controlled. We also proved the validity of our predictions of hydrodynamic forces on the blade and the turbine, made through CFD calculation, by comparing them with the results of corresponding model tests in a current channel. In the corresponding model test we investigated not only the hydrodynamic forces on the turbine with three fixed blades, but also the inline force and the cross-flow force on the rotating turbine with three blades. Regarding the cyclic pitching of turbine blades, results suggest that significant increase in average turbine torque is possible.

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Water Power Development: Low-Head Hydropower Utilization

Developments in Hydraulic Engineering ◽

10.1201/9781482286397-8 ◽

1988 ◽

pp. 12-111

Keyword(s):

Power Development ◽

Water Power ◽

Low Head

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Investigating barotrauma in juvenile salmon passing through a very low head turbine using response surface methodology

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/09544062211050447 ◽

2021 ◽

pp. 095440622110504

Author(s):

Mehrshad Foroughan ◽

Alireza Riasi ◽

Amir Bahreini

Keyword(s):

Chinook Salmon ◽

Cfd Simulation ◽

Geometrical Parameters ◽

Innovative Design ◽

Computational Costs ◽

Water Turbine ◽

Low Head ◽

Computational Fluid Dynamics Cfd ◽

Biological Performance ◽

Riverine Fish

Although hydropower is a clean source of energy, in some cases, it can jeopardize the life of some species of riverine fish. Very Low Head (VLH) water turbine is an innovative design that aims at reducing the adverse effects of such hydroelectric facilities. In this research, two methodologies are integrated to investigate barotrauma in juvenile salmons passing through this particular turbine. First, to quantify barotrauma, we implement a method known as BioPA (Biological Performance Assessment) by combining the results of some laboratory experiments on juvenile Chinook salmon moving through a simulated turbine passage with the Computational Fluid Dynamics (CFD) simulation of the flow field in this environment. In the second part, we added surrogate-based modeling as a tool, which enabled us to study the effects of two geometrical parameters on the environmental performance of the VLH turbine with low computational costs. The results indicate a significant dependency between the installation angle of the VLH turbine and the severity of the barotrauma of this particular fish. In addition, further investigations suggest that the region near the middle of blades is the safest for fish in the case of decompression.

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The Helical Turbine and Its Applications for Hydropower Without Dams

Advanced Energy Systems ◽

10.1115/imece2002-33193 ◽

2002 ◽

Cited By ~ 1

Author(s):

Alexander M. Gorlov

Keyword(s):

Cross Flow ◽

Environmentally Friendly ◽

Open Ocean ◽

Water Currents ◽

Low Head ◽

Tidal Streams

The objective of this paper is to introduce an environmentally friendly Helical Turbine that has been developed to operate in free or ultra low-head water currents without dams. The turbine is a cross flow unidirectional rotation machine that makes it particularly valuable for ocean applications, such as reversible tidal streams in ocean bays, estuaries and canals, streams in open ocean, underwater currents generated by wave fluctuations etc.

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