Investigation of Dynamic Characteristics of Multi-Bladed S-Shaped Vane Type Rotor (original) (raw)
Related papers
Journal of Mechanical Engineering, 2015
This paper reports on the experimental investigation of the aerodynamic effects on even and odd number bladed vertical axis vane type rotor. The experiment was conducted with the help of a subsonic wind tunnel together with the experimental setup of the vane type rotor and a spring balance. To ensure a Reynolds number independent approach, different stream flow was maintained. The flow velocities varied from 5 m/s to 9 m/s covering the Reynolds number from 0.6375 X 10 5 to 1.2 X 10 5. A four, five and six bladed vertical axis vane type rotor was used to determine the aerodynamic properties in dynamic condition. It is found that the power coefficient increases with increasing the number of blade but the significant effect of even and odd number blade is observed on the range of tip speed ratio. An odd number bladed rotor covered a wide range of tip speed ratio compare to the even number one.
In this paper, variation of static torque and drag coefficient of an S-Shaped Savonius rotor have been studied for different number of rotor blades. This has been done by measuring the pressure distribution on the blade surfaces for different rotor angles. All the experiments have been carried out at Reynolds number 1.07x105 in a uniform flow jet produced by an open circuit wind tunnel. Experimental results indicate that both of the drag force and hence the torque change frequently with rotor angle. It is also found that as the increase of the number of rotor blade increases the starting torque of rotor increases but there is no significant increase in net torque output. It is observed that, torque distribution becomes more uniform as the number of blade of rotor increases.
International Journal of Mechanical Engineering and Robotics Research, 2021
The savonius rotor is a vertical-axis wind turbine which operates according to the drag forces. It is widely used as equipment with the wind as a source of energy and has a simple design, it is easy to install, good starting ability, relatively low operating speed, and independent of wind direction. Several studies have been conducted in the last decade to improve the performance of this equipment with the focus on the aspect ratio, overlap ratio, and installing additional devices such as curtain design, deflector plate, guide box tunnel, and windshields. Swirling savonius rotor is an improvement on the savonius rotor with a gap between the concave and convex blades to reduce the negative torque generated by the convex blade. This present study was conducted to analyze the power coefficients, drag coefficients, and static torque of a swirling savonius rotor with omnidirectional guide vanes by measuring the pressure distribution on the blade surfaces at different rotor angles. The experiments were conducted at a Reynolds number of 1,1x10 5 with the rotor having two semi-circular blades, an overlap ratio of 0,2, and the number of omnidirectional guide vanes varied at 4, 8, 12, and 16. The results showed all the omnidirectional guide vanes except 16 increased the static torque and drag coefficients of the swirling savonius rotor.
Aerodynamic characteristics of a five bladed S-shaped savonius rotor
2016
The S-shaped rotor is a modification of the Savonius rotor with no overlap. Drag and torque coefficients of a five bladed S-shaped Savonius rotor have been investigated by measuring the pressure distribution on the blade surfaces for various rotor angles. The experiments have been carried out at a Reynolds number of 2.1x105 in a uniform flow jet produced by an open circuit wind tunnel. To calculate drag force and torque in non-dimensional form, the data are taken on 12 pressure tapping points on each blade of the five bladed S-shaped Savonius rotor for every 100 interval of the angle of rotation. The pressure distributions both on the concave and convex surface of the blade at different angle of rotation are presented graphically. At rotor angle α = 400, difference of pressure coefficient on convex surface and concave surface is maximum. At rotor angle α = 3100, difference of pressure coefficient on convex surface and concave surface is minimum. The measurements indicate that drag f...
APPLIED PHYSICS OF CONDENSED MATTER (APCOM 2019)
Rising demand for energy due to industrial development has led to the depletion of fossil fuels, which adversely affect climate change due to fossil fuel emissions. Wind energy is one of the most available popular sources of renewable energy are rapid growth. At the present vertical axis wind turbine (VAWT) is one of the kind of machines that used to produce electricity. The aerodynamics of a VAWT are very complex due to the dynamic stall when the blade of the turbine is an airfoil. Low starting torque is the wind turbine disadvantage when the airfoil is used as a blade. A computational fluid dynamic CFD is used to simulate the aerodynamic characteristics of the current model (coupling of the three blades VAWT with a movable vane). (SST) k-ω turbulence and finite volume method were used to solve the aerodynamics of the flow around the current model by using ANSYS FLUENT 16.1 software's. The finding results from the numerical simulation show that the drag coefficient (Cd), static pressure drop and starting torque are increased in the positive side and decreases in the negative side of the turbine rotor. The movable vanes which are coupled with airfoil for each blade help the coming airflow passing freely between the vanes at the negative blade position in case of all the vanes are totally open, at this case the resistance coming from the air in the airflow direction is reduced to becoming near zero. Reducing the airflow resistance in the negative side of the turbine blades help to increase the rotation of the turbine rotor, then the output power from the turbine increases.
Investigation of the Parameters Effect on the Rotor Wind Turbine
This paper presented the effect of weight, number of frames and the rotational speed of the rotor on wind turbine efficiency, the greater the number of frames in rotor the exposed area of the air will increase, and therefore that increasing the amount of torque generated, concomitant increase in weight, the higher weight will be caused slow rotational speed. The practical test show that the 4-frame rotor wind turbine gives slightly higher torque than 3-frame rotor wind turbine, however, the power coefficient for 3-frame wind turbine model is higher than of 4-frame wind turbine model for the same wind velocity.
IJERT-Computational Fluid Dynamics Analysis of Two-Bladed and Three-Bladed H-Darrieus Rotors
International Journal of Engineering Research and Technology (IJERT), 2021
https://www.ijert.org/computational-fluid-dynamics-analysis-of-two-bladed-and-three-bladed-h-darrieus-rotors https://www.ijert.org/research/computational-fluid-dynamics-analysis-of-two-bladed-and-three-bladed-h-darrieus-rotors-IJERTCONV9IS11020.pdf From the past few decades, the demand for renewable energy has increased rapidly. Among all the available energy sources, wind energy is one of the finest forms of renewable energy with so lesser pollution and harm to the environment. Wind turbines are a type of device which produces energy from the wind. These wind turbines are mainly of two types, Horizontal axis wind turbines (HAWTs) and vertical axis wind turbines (VAWTs). HAWTs are popular to use commercially, but the development and research on the VAWTs are increasing gradually nowadays. In this present work, a brief review of the performances of two-bladed and three-bladed H-Darrieus rotors has been done considering different performance parameters like tip speed ratio, solidity, power coefficient, etc. The performance of the two-bladed and three-bladed wind turbine having an H-Darrieus rotor having NACA0018 profile with a solidity of 0.12, TSR of 4.5 have been compared and we have seen the optimum power coefficient (Cp) of the two-bladed rotor has a higher Cp value of 0.41 than the Cp value of 0.38 of the three-bladed rotor.
International Journal of Smart Grid and Clean Energy, 2016
A thorough understanding of the principles of aerodynamics and structural dynamics of the rotor system is required for designing a wind turbine system that can generate power with high efficiency. The power generated by a Vertical Axis Wind Turbine (VAWT) depends on the drag force generated by the individual blades and interactions between them in a rotating configuration. The present analysis is an attempt to predict numerically the coefficient of drag and other aerodynamic parameters for a three and four blades Vane type Vertical Axis Wind Turbine (VVAWT) with different blades and vanes position. Commercial Computational Fluid Dynamics CFD softwares GAMBIT and FLUENT are used in the numerical analysis where the Shear Stress Transport (SST) k-ω turbulence closure model is used. The results are found to be similar in nature to those reported for VAWT having different blade designs.
Simulation Study on the Performance of Vertical Axis Wind Turbine
Applied Mechanics and Materials, 2013
The present study considered the design improvement of Savonius rotor, in order to increase the efficiency of output power. An investigation was conducted to study the effect of geometrical configuration on the performance of the rotor in terms of coefficient of torque, coefficient of power and power output. Modification of conventional geometry has been designed by combining the effect of number of blades and shielding method. CFD simulation was conducted to analyze the flow characteristic and calculate the torque coefficient of all the rotor configurations. The continuity and Reynolds Averaged Navier-Stokes (RANS) equations and realizable k-ε epsilon turbulence model are numerically solved by commercial software Ansys-Fluent 14.0. The results obtained by transient and steady method for the conventional two bladed Savonius rotor are in agreement with those obtained experimentally by other authors and this indicates that the methods can be successfully applied for such analysis. The...
Journal of University of Babylon for Engineering Sciences, 2021
The paper gives an experimental study on the performance on the wind turbine rotors with several numbers of blades as well as twist angle. The main goal of this study is to demonstrate the effect blades number, tip angles as well as the twist angle of the blades on the power coefficient (Cp) of the rotor. Moreover, this result represents a simple evaluation about the range of depending power coefficient on the average wind speed. Also, this paper studies the performance of wind turbines which are tested by carrying out 2dimensional dynamic using ANSYS-Fluent.