scholarly journals The effect of along blade surface discretization on the Savonius hydrokinetic turbine performance by using Myring formula for n = 1

2020 ◽  
Author(s):  
Priyo Agus Setiawan ◽  
Rini Indarti ◽  
Nopem Ariwiyono ◽  
Subagio So’im ◽  
Muhammad Shah ◽  
...  
Keyword(s):  
Blade Surface ◽  
Turbine Performance ◽  
Hydrokinetic Turbine

Numerical Modeling and Optimization of Hydrokinetic Turbine

2011 ◽  
Author(s):  
Nitin Kolekar ◽  
Suchi Subhra Mukherji ◽  
Arindam Banerjee
Keyword(s):  
Numerical Modeling ◽  
Transient Analysis ◽  
Stokes Equations ◽  
Three Dimensional ◽  
Turbulence Models ◽  
Coefficient Of Performance ◽  
Speed Ratio ◽  
Turbine Performance ◽  
Design Variables ◽  
Hydrokinetic Turbine

Hydrokinetic turbines, unlike conventional hydraulic turbines are zero head energy conversion devices which utilize the kinetic energy of flowing water for power generation. The basic operational principle of the horizontal axis hydrokinetic turbine (HAHkT) is same as the wind turbine, the only difference being change in working media: water instead of air. This paper discusses the hydrodynamic design of HAHkT via numerical modeling. Presently these turbines suffer from low coefficient of performance (Cp) which is governed by several design variables such as tip-speed ratio, chord distribution, solidity and number of blades. The numerical modeling is performed for both constant and varying chord geometries using commercially available computational fluid dynamics software (CFX/FLUENT) to understand the effect of each of the design variable on turbine performance. Since the flow Reynolds number is large (≥ 105), both one- and two-equation turbulence models are applied to solve Reynolds Averaged Navier Stokes equations. In addition, a three dimensional analysis of HAHkT is performed to give a better insight into the effect of tip vortices and flow separation phenomenon on turbine performance; the results are then compared with Blade Element Momentum (BEM) theory analysis. In addition, a procedure for a multivariate optimization scheme is discussed that aims at maximizing Cp for a constant flow velocity while maintaining optimum values of critical design variables listed above. Finally, the effect of variation of angle of attack on the flow around a hydrofoil is investigate using both static and transient analysis, the transient analysis being performed by subjecting the airfoil to periodic oscillations.

scholarly journals Experimental, Numerical and Application Analysis of Hydrokinetic Turbine Performance with Fixed Rotating Blades

Energies ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 766 ◽  
Author(s):  
Faruk Guner ◽  
Hilmi Zenk
Keyword(s):  
High Altitude ◽  
Flow Rate ◽  
Stream Flow ◽  
Water Flow Rate ◽  
Electricity Production ◽  
Rotating Blades ◽  
Turbine Performance ◽  
Hydrokinetic Turbine ◽  
Application Analysis ◽  
Investment Cost

In this study, a hydrokinetic turbine is designed for the high-altitude regions where local electricity network lines are difficult to reach. If there was a stream flow around, electricity production could be possible and necessary because of environmental reasons. The performance of the hydrokinetic turbine was investigated experimentally and numerically. The numerical analyses of the turbine system were performed via MATLAB/Simulink version R2014a. Except power-based performance characteristics, efficiency of the system in terms of installation and necessary investment costs were also investigated. It is calculated that the system to be established on a river with a water flow rate of 30 m3/h will meet the investment cost in approximately 8 years.

INVESTIGATION OF TORQUE GENERATION CAPABILITY OF MIXED FLOW TURBINE UNDER STEADY STATE CONDITIONS

2017 ◽  
Vol 79 (7-3) ◽  
Author(s):  
M. A. S. Izaiddin ◽  
A. F. Mustaffa ◽  
M. H. Padzillah
Keyword(s):  
Mass Flow ◽  
Leading Edge ◽  
Maximum Efficiency ◽  
Blade Surface ◽  
Mixed Flow ◽  
Factors Affecting ◽  
Turbine Performance ◽  
Radial Turbine ◽  
Torque Generation ◽  
Edge Surface

A mixed flow turbine is a type of turbine that is used mostly in turbocharger engine for vehicle. The ability of this turbine in obtain maximum efficiency on a wider operating range makes it more favorable compared to axial turbine and radial turbine. In this project, one of the factors affecting turbine performance which is torque has been studied using simulation. The simulation is then being run by varying the mass flow supply to the turbine. In this simulation, torque generation has been identified and plot on the entire blade surface. This torque generation capability is then been compared between 0.25 kg/s, 0.45 kg/s and 0.65 kg/s mass flow. From the simulation, the torque generated is founded to fluctuate along the turbine blade surface. Besides, the torque generated at the leading edge and trailing edge surface are negative. The magnitude of torque generated increases, as the mass flow increased. At the mid span of the blade, torque generated at 0.25 kg/s, 0.45 kg/s and 0.65 kg/s is -3.73 X 10-3Nm, 4.33 X 10-3Nm, and 11.8 X 10-3Nm respectively.

Numerical Analysis of Blockage Ratio Effect on a Portable Hydrokinetic Turbine

2016 ◽  
Author(s):  
Cosan Daskiran ◽  
Jacob Riglin ◽  
Alparslan Oztekin
Keyword(s):  
Free Stream ◽  
Numerical Study ◽  
Three Dimensional ◽  
Turbine Rotor ◽  
Power Coefficient ◽  
Stream Velocity ◽  
Blockage Ratio ◽  
Ratio Effect ◽  
Turbine Performance ◽  
Hydrokinetic Turbine

Three-dimensional steady state Computational Fluid Dynamics (CFD) analyses were performed for a pre-designed micro-hydrokinetic turbine to investigate the blockage ratio effect on turbine performance. Simulations were conducted using a physical turbine rotor geometry rather than low fidelity, simplified actuator disk or actuator lines. The two-equation k-ω Shear Stress Transport (SST) turbulence model was employed to predict turbulence in the flow field. The turbine performance at the best efficiency point was studied for blockage ratios of 0.49, 0.70 and 0.98 for three different free stream velocities of 2.0 m/s, 2.25 m/s and 2.5 m/s. Distinct blockage ratio results at a free stream velocity of 2.25 were compared to a previous numerical study incorporating the same rotor geometry within an infinite flowing medium. The pressure gradient between turbine upstream and turbine downstream for blocked channel flows elevated the turbine performance. The increment in blockage ratio from 0.03 to 0.98 enhanced power coefficient from 0.437 to 2.254 and increased power generation from 0.56 kW to 2.86 kW for the present study.

Hybrid viscous/inviscid modelling of a hydrokinetic turbine performance and wake field

2020 ◽  
pp. 553-562
Author(s):  
M. Gregori ◽  
D. Calcagni ◽  
F. Salvatore ◽  
F. Di Felice ◽  
F. Alves Pereira ◽  
...  
Keyword(s):  
Wake Field ◽  
Turbine Performance ◽  
Hydrokinetic Turbine

Formation Process of Water Film and Performance Effect on Compressor Stage

2016 ◽  
Author(s):  
Hai Zhang ◽  
Xiaojiang Tian ◽  
Xiaojun Pan ◽  
Jie Zhou ◽  
Qun Zheng
Keyword(s):  
Gas Turbine ◽  
Formation Process ◽  
Water Injection ◽  
Water Film ◽  
Compressor Stage ◽  
Blade Surface ◽  
Water Droplets ◽  
Compression Process ◽  
Turbine Performance ◽  
Wet Compression

In process of wet compression, gas turbine engine will ingest a certain amount of water, which can influence the overall performance of the engine. This phenomenon is particularly significant in the cleaning process of industrial gas turbine and water injection of aero-engine. When the quantity of water ingestion is quite large, the performance of gas turbine will appear deterioration and may lead to flameout, power reduce or even shutdown of the engine, causing accidents. Water droplets will be accumulated on the blade surface where water films could be formed on pressure surface in the wet compression process. The effects of water film on gas turbine engines are aerodynamic, thermodynamic and mechanical. The above-mentioned effects occur simultaneously and be affected by each other. Considering the above effects and the fact that they are time dependent, there are few gas turbine performance researches, which take into account the water film phenomenon. This study is a new research of investigating theoretically the water film effects on a gas turbine performance. It focuses on the aerodynamic and thermodynamic effects of the phenomenon on the compressor stage. The computation of water film thickness, which frequently be formed on the surface of compressor blade, its movement and extra torque demand, are provided by a simulation model of the code. Considering the change in blade’s profile and the thickness feature of the water film, the compressor stage’s performance deterioration is analyzed. In addition to this, movement and the formation of the water film on a compressor stage are simulated and analyzed by using unsteady numerical methods under different water injecting conditions in this paper. The movement characteristics of water droplets in compressor passage are investigated to understand the flow mechanisms responsible for water film formation process. The forming and the tearing process of water film on blade surface are analyzed at different injection conditions. For simulating the real situation, The maximum quantity of injected water can reach 12%. The results indicate that continuity and region of the water film on the blade surface will be developed with the increment of droplet size and injection rate. It is also found that the flow losses near blade surface increases with the tearing process of water film due to the increment of surface roughness.

scholarly journals EFFECT OF FLOW STEERING ANGLE TOWARD THE HYDROKINETIC TURBINE PERFORMANCE

2019 ◽  
Vol 3 ◽  
pp. 20-31
Author(s):  
Rudy Soenoko ◽  
Hastono Wijaya
Keyword(s):  
Kinetic Energy ◽  
Water Flow ◽  
Flow Rate ◽  
Turbine Blades ◽  
Water Flow Rate ◽  
Rate Variation ◽  
Steering Angle ◽  
Turbine Performance ◽  
Hydrokinetic Turbine ◽  
Turbine Runner

The kinetic turbine is one of the solutions for use in low-speed river flows ranging from 0.01–2.8 m/s. This kinetic turbine is used as a conversion equipment to convert the water kinetic energy into an electrical energy. The working principle of a kinetic turbine is utilizing and relies on the water kinetic energy. Water flowing into the turbine area will produce a momentum on the turbine blades. This momentum change would then push the turbine blades and finally spin the turbine runner. The aim of research is thedetermination of the effect of water flow steering angle (a) and water flow rate variation in the kinetic turbine performance. This research uses vertical axis kinetic turbines with eight curve blade attached to the turbine runner. The variables used are two values of water flow steering angle, namely 25°and 35°. The water flow rate variation of 30 m3/h, 35 m3/h, 40 m3/h and 45 m3/h. The method used in this study uses a real experimental method. These two variations would then compare with the result of a hydrokinetic turbine performance done on the previous research. The results show that the water flow steering angle a affected the kinetic turbine performance (power, efficiency and torque). From these several water flow steering angle and water flow rate variations, the turbine performance with a 35° water flow steering angle get the highest performance compared with the use of 25° and 14° water flow steering angle. The greater the flow angle and the greater the water flow rate, the greater the torque, power and efficiency. The highest turbine power produced, P=17.5 W, occurs on the 35° water steering angle, and on a Q=45 m3/h water flow rate and on a 80 rpm turbine rotation. While the highest turbine efficiency, h=27 %, occurred on the Q=30 m3/h water flow rate, on a 60 rpm turbine rotation and on a water flow steering angle a=35°. The highest turbine torque, 3.1 Nm, occurs at Q=45 m3/h water flow rate at a maximum turbine braking and on a water steering angle a=35°.

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