Cross-flow Hydraulic Turbine Research Articles

Development of an undershot cross-flow hydraulic turbine resistant to snow and ice masses flowing in an installation canal

This study developed a microhydraulic turbine that can stably and efficiently generate electricity even in canals where snow and ice masses frequently flow down. An undershot cross-flow hydraulic turbine was selected as the development target, and experiments were conducted in an irrigation canal in a heavy snowfall area. Spherical snowballs were made to flow down to the turbine from the upstream direction. The behavior of the snowballs and the power generation performance were investigated as these snowballs passed through the rotor. When the diameter of the snowball is smaller than the blade interval of the rotor, the snowball passing through the rotor causes a small decrease in power output. In contrast, when the diameter of the snowball is larger than the blade interval, the snowball is entrained between the rotor and canal bottom, temporarily stopping the rotor, and resulting in a large decrease in power generation. These results suggest that an undershot cross-flow hydraulic turbine can reduce power generation performance due to snow and ice masses when its blade interval is larger than the expected size of the snow and ice masses. This study developed some design guidelines for this turbine that are highly adaptable to snow- and ice-flowing irrigation canals.

Development of an Undershot Cross-Flow Hydraulic Turbine Resistant to Snow and Ice Masses Flowing in the Installation Canal

Development of an Undershot Cross-Flow Hydraulic Turbine Resistant to Snow and Ice Masses Flowing in the Installation Canal

Experimental and numerical studies on flow and torque mechanisms of open cross-flow hydraulic turbine

The flow and torque mechanisms of an open cross-flow hydraulic turbine in an underflow operation are investigated through experiments and numerical simulations. The unsteady flow field around a hydraulic turbine is measured in an open-circuit water tunnel using phase-averaged particle image velocimetry, and the results are compared with those of a two-dimensional numerical simulation using the volume of fluid method for two-phase flow analysis. The experimental and numerical results of the flow field agree well with each other, suggesting the validity of the two-dimensional numerical simulation for open cross-flow hydraulic turbines. The experimental and numerical results indicate that both the accelerated flows over the downstream blade and through the bottom spacing between the turbine and channel wall yielded the positive torque generation of the cross-flow turbine. The former effect is caused by the stagnation pressure on the concave side of the blade and the formation of accelerated flow on the convex side of the blade, both of which are observed at a low tip-speed ratio. The latter effect of bottom spacing is caused by the converging flow effect of the local velocity between the lower side of the turbine and the channel wall. It is discovered that these flow features improved by decreasing the bottom spacing, and that they contributed to the local torque generation; consequently, the torque performance and efficiency of the cross-flow turbine improved. However, very small bottom spacing may not be effective for improving the efficiency.

Experimental and numerical studies on the performance of a waterfall-type cross-flow hydraulic turbine

The performance of a waterfall-type cross-flow hydraulic turbine was investigated via experiment and numerical simulation. The experiment was carried out using a cross-flow hydraulic turbine operating in a two-dimensional waterfall, and the result was compared with a corresponding numerical result analyzed by the volume of fluid method. The experimental results show that the maximum efficiency reached approximately 60%, higher than that of previous experiments in the literature. It was also confirmed that the recorded experimental efficiency was well reproduced in a two-dimensional numerical simulation, suggesting the validity of the numerical results. Furthermore, flow fields of the turbine were studied based on phase-averaged particle image velocimetry measurement and the numerical simulation. These results indicate that the flow and torque mechanisms of the cross-flow hydraulic turbine studied are explained by stagnation pressure on the concave side of blades and a Coanda-like flow on the convex side of the blades at small angle of blade position, followed by the formation of a high-velocity region within the turbine and flow impingement on the downstream blades at large angle. These flow field variations generated an increased local torque at small angle and a moderate torque at large angle. The improved efficiency was obtained by optimizing the off-axis distance to the waterfall and the tip-speed ratio of the hydraulic turbine, which were examined by a visualization of the flow through the turbine and the local torque distribution with respect to the angle of blade position, respectively.

Perancangan Model Pembangkit Listrik Dengan Menggunakan Teknologi Pompa Tanpa Motor (Hydraulic Ram Pump)

This paper presents the design of parameters of hydraulic ram pump and hydraulic turbine to use the energy of flowing water for water supply to generate electrical power and irrigation. Design of parameters of hydraulic ram pump with head of water supply of 1,5 m was obtained: 1,25 in. diameter and 8 m length of drive pipe, 200 gr and 4,6 cm of weight and diameter of impulse valve, 4.200 cm3 of air chamber volume. The testing results of the hydraulic ram pump model shown that water could be pumped as far as the height of 7 m and 8 m, with the volume flow rate of 2,755 lit/men and 1,73 lit/men. Design of geometric parameters of cross flow hydraulic turbine with head of water supply of 1,75 m was obtained: 12 cm and 8 cm of external and internal diameter, 25 cm of runner width, and 18 of runner number. The testing results of the cross flow hydraulic turbine shown that power could be generated 83,47 W with the volume flow rate of 0,01 lit/s and the efficiency of 71,05 % at 799 rpm. The testing result also shown that with using volume flow rate of 0,003 lit/s, this turbine could be generated 23,39 W with the efficiency of 46,64 %. Technically the technology of hydraulic ram pump can be developped and used to supply of water for irrigation and generating of electrical power.

Internal Flow and Performance of Cross-flow Hydraulic Turbine

Internal Flow and Performance of Cross-flow Hydraulic Turbine

An Experimental Investigation of the Performance of Cross-flow Hydro Turbines

Renewable energy is the need of developing countries and cross-flow turbine is a promising means of small scale hydro-power production in locations where available head and discharge is comparatively low. The present work refers to experimental analysis of performance of cross-flow turbine for low head, low discharge sites. The work deals with the key parameters influencing the efficiency of the cross-flow hydraulic turbine which includes outer diameter of runner, breadth of the runner, angle of attack, thickness of water jet, spacing of blades in the runner, radius of blades curvature, number of blades, the blade exit angle for first stage and angle between relative velocity of entering water jet and turbine outer periphery. The variation of efficiency and runner speed with different angle of attack, nozzle tip elevation and nozzle tip distance from runner is analyzed in the present work. The runner consists of 12 blades symmetrically arranged between two circular end plates at the plate periphery. The setup is prepared for the sites where head available is relatively medium or low. The inlet angle β1 of blade is maintained at around 26º to 28º and outlet angle β2 as 90º i.e. outlet is radial. The key parameters such as nozzle inlet angle, nozzle tip elevation and its horizontal distance from center of the runner shaft are varied for different heads as per different site configurations.

Design and Computational Fluid Dynamic Simulation Study of High Efficiency Cross Flow Hydro-power Turbine

Cross-flow hydraulic turbine becomes viable in low head and small water flow rate. Because of its simple in structure and ease of manufacturing, it is familiar in scheme of small hydro-power in the site of the power plant. In order to obtain a cross-flow turbine with maximum efficiency, appropriate turbine design must be performed. Therefore here proper turbine design was done employing the all turbine parameters and computational fluid dynamic simulation was carried out as important tool for performance study of the turbine. The required turbine model was designed and computational fluid dynamics simulations was performed by using the commercial software ANSYS CFX v.12. After the high efficiency turbine was designed, computational fluid dynamics was conducted in order to validate the obtained solution. With attack angle of 180, maximum efficiency was found to be 82.52% constant for different values of head and water flow rate. Where as in CFD simulation case, maximum efficiency became 79% with fully opened guide vane. Guide vane was set at position where the water is discharge through the runner fully. In this paper all design parameters of cross-flow turbine were calculated at maximum efficiency and simulation was done by opening turbine gate value at different stages.

An Experimental Study on Performance Analysis of Cross-Flow Water Turbine

Renewable energy is the need of less developed countries and cross-flow turbine is a promising means of small scale hydropower production in locations where available head and discharge is comparatively low. The present work refers to experimental analysis of performance of cross-flow turbine for low head, low discharge sites. The work deals with the key parameters influencing the cross flow turbine efficiency. The efficiency of the cross-flow hydraulic turbine is dependent on several design parameters. These include runner outer diameter, breadth of the runner, thickness of water jet, number of blades, spacing of blades in the runner, radius of blades curvature, angle of attack, the first stage blade exit angle and angle between relative velocity of entering water jet and turbine outer periphery. The variation of efficiency and runner RPM with different angle of attack, nozzle tip elevation and nozzle tip distance from runner is analysed in the present work and selections have been made based on quantitative methods and experimental studies already carried out by different researchers.

Numerical study on the flow and performance of an open cross-flow mini-hydraulic turbine

This study simulates the flow through a small-scale open cross-flow hydraulic turbine and analyzes the turbine’s performance. The simulation employs a two-dimensional particle method that was used for the simulation of a small-scale impulse-type hydraulic turbine in a prior study. Flow in the turbine is successfully simulated, with the simulated turbine performance showing good agreement with experimental measurements. The simulations also clarify that the deterioration in performance with increasing water flow rate is caused by the degeneration of the radially outward flow between the rotor blades.

Shaft fatigue life and efficiency improvement of a micro cross flow turbine

Article history: Received September 20, 2013 Received in Revised form October, 14, 2013 Accepted 20 December 2013 Available online 1 January 2014 The present study deals with optimization of hydraulic efficiency and shaft fatigue life of a micro cross-flow hydraulic turbine. A micro cross-flow turbine (KTP-B60) with shaft fatigue failure was considered as a case study. Numerical flow simulations were performed using a 3Dtwo phase flow solver, and the results have shown a good agreement with experimental data. Using an analytical method, the shaft fatigue factor of safety (FOS) was extracted from numerical simulation. CFD results were utilized in the optimization process in order to improve hydraulic efficiency and shaft fatigue life simultaneously using a metamodel (Artificial Neural Network) and genetic algorithm (GA). The priority of hydraulic efficiency and shaft fatigue life was altered by defining different objective functions in the optimization process. In one of the cases comparison of initial and optimal turbine showed a hydraulic efficiency improvement of 10.14 % and relative shaft FOS improvement of 4.86 %. The proposed optimization method could be exploited as an efficient and low cost procedure for energy generation improvement in micro hydro turbines. © 2014 Growing Science Ltd. All rights reserved.

Investigation of Opened Cross-flow Hydraulic Turbine for Waterfall

Investigation of Opened Cross-flow Hydraulic Turbine for Waterfall

Performance and Internal Flow Characteristics of a Cross-Flow Hydro Turbine by the Shapes of Nozzle and Runner Blade

Recently, small hydropower attracts attention because of its clean, renewable and abundant energy resources to develop. Therefore, a cross-flow hydraulic turbine is proposed for small hydropower in this study because the turbine has relatively simple structure and high possibility of applying to small hydropower. The purpose of this study is to investigate the effect of the turbine's structural configuration on the performance and internal flow characteristics of the cross-flow turbine model using CFD analysis. The results show that nozzle shape, runner blade angle and runner blade number are closely related to the performance and internal flow of the turbine. Moreover, air layer in the turbine runner plays very important roles of improving the turbine performance.

마이크로 관류수차의 상수도 관로시스템 적용에 관한 연구

Recently, micro hydropower and it's useful utilization are taking a growing interest as a countermeasure of global worming by carbon dioxide and exhaustion of fossil fuel. The purpose of this study is to investigate the possibility of extracting micro hydropower wasted by a valve in water supply system using micro cross-flow hydraulic turbine. In order to fulfill the functions of controlling flow rate and pressure in substitute for the valve, air and water are supplied into an air suction hole which is installed on the side wall of micro cross-flow hydraulic turbine. The results show that in case of supplying a lot of air into the air suction hole, about 50% of flow rate and relatively high value of loss coefficient are controlled by the turbine. Moreover, including high possibility of applying the micro cross-flow turbine to water supply system, extended application of the turbine to the water discharge system of drainage and irrigation canal.