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shallow water tide generating system
1Laly James, 2Sarin C R, 3 Teena George, 4Tinu Francis& 5Robert V Mathew
1,2,3,4
Dept of Electrical and Electronics Engineering, Vimal Jyothi Engineering College,
5Dept of Mechanical Engineering, Kauz University, Europe
Abstract - Progressive and optimum design can improve the performance of a tidal turbine significantly. It has been substantiated that a small fraction of change in speed of the turbine can create a large change in output, theoretically up to 400 %. As the speed of the inputtide wave cannot be attuned, the best practice is to increase the speed of the available tide waves to the turbine using some buffer methods like gores or penstock. A lens diffuser which has a varying perimeter throughout its axial length and set around the turbine blades can increase the speed of the turbine considerably. The proposed system facsimiles a tidal turbine model with a diffuser lens integrated with it.
It is identified that output of the system is increasedup to 139 % after the induction of tidal lens.
I. INTRODUCTION
The ever rising population, expanding energy, environmental issues and escalating fuel prices has created a statuses to make use of reliable and renewable energy sources. One of the superlative available form of renewable energy sources are tidal waves. As 70% of the earth is oceanic and it was found that more than 40 percentage of ocean area is having some potential of moving current of water and fit for tidal energy. Tidal energy is considered as the best source of renewable energy after solar power. Tidal wave is engendered do to the relative motion between planetary elements especially sun, earth and moon. The output of the title energy depends on the rate of change of kinematic and fluid properties of the wave.
A tidal power plant has really highly initialization and installation cost but still has the ability to produce really cheap electricity, much predictive than windfarms, highly reliable, produces renewable form of energy and much cost effective. Even though it has many advantages, it is less utilized due to its operational strategies. May recent advancements have been developed in tidal power sector in recent ages and it is expected that within 2050, a fraction of total power generation in the world will be from tidal power plants.
The power developed in a tidal turbine will depend on many factors such as effective area available for the tides, the density of the water and the velocity of the turbine to its third power. So if the speed of the turbine is increased by a factor of one, the speed will be increased for a factor of power of three. As the speed of tide of waves spreads cannot be adjusted, the best
practice is adjust available is to improve effective tide velocity to the turbine. There are many methods for controlling the speed which is include penstock based control, geared control, auxiliary actuator gears driven system, gravitational altitude adjustment and lens based control. Pen stroke based control and gravitational attitude adjustment based control need added altitude changes and reservoir at different altitude level which is less favorable in many cases. The auxiliary controland geared control need an active control which is also lessfavorable. The best way of controlling is to use wind lens based control.
The projected system laidback on a vortex lens based horizontal axis type turban which has is diffuser lens tied around the turbine system blades. Such a system will intake the tidal wave through the lens and the varying diameter of the system will create a pressure difference throughout the horizontal axis. This will create an increase in speed as the pressure differs at a definite proportion. A fraction of increase in speed will create corresponding increase in output. The proposed system model is simulated using Matlab and characteristic features and deficiencies have been identified. The system is remodeled so that a system which can provide maximum efficiency. The system is fabricated in real time and characteristic features are analyzed.
II . STRATEGIES AND MODELING
Many models of tidal power plants have been proposed and each have its own characteristic features advantages and disadvantages what is the primary model for wind turbine is proposed by which has a blade based turbine system that I will that I will rotate planes and generate electricity the test statistic equation the characteristic equation that defines the output of the turbine system is that
P = Cp x 0.5 x ρ x A x V³
Where P stands for the output power, ρ for the density of the water, A for the effective area and V for the velocity of the tidal wave. It should be noted that if the velocity is increased, the output will be increased by a factor of third power. All other factors such as density, area and coefficient of viscosity cannot be adjusted more than a certain level. So the design model should be focused on
increasing the speed of the turbine blades so as to achieve higher output. There are many methods for improving the speed and the proposed system procedures a diffusion based speed control where the turbine blades are placed in a vortex based tunnel pipe.
The speed of the fluid that reaches the turbine blade depends on pressure difference across the tunnel. If there is a large pressure difference across the internal periphery, the speed will be more. So it is possible to create a linearly varying still has large difference, across the tower tunnel that can produce a very high speed wavesusing a tunnel. Such an arrangement where the area of the system is reduced, the pressure will be reduced so that the water will flow in very high velocity.Still it may create some swirl across the tenets which can be reduced by remodeling the system internal projections and it is added in this system. This system is also having some dependency over the operation of blends which can be improved by using gravity based arrangements.
Figure I
A lens based system will have a tunnel around the turbine blade across the horizontal axis as shown in figure 1. Subsequently the turbine blade system will be rotating inside the tunnel which has a varying diameter throughout its axial length. This will create a differential pressure transformationacross the tunnel which depends on the diameter of the tunnel at various ends. The pressure level inside the system will be less than as that of the pressure difference outside the turbine. The pressure will be at its least at outlet part nearer to the turbine blades. Thus the wave draw more tidal waves towards the blades as that of a bare tidal turbine which is exposed to the outside world.
III. MATHEMATICAL MODELING
In such systems, the torque produced will be equal to, Rotor torque TR = KtθR2 (1)
If θR is the angular velocity, Shaft constant Ktcan be defined as :
K=1
2πρRr5COPT * 1/λOPT (2) The relation of the rotor speed Өiwith respect to the
This is the radius of the plate is increased, this will also increase still the radius of the blade cannot be increased beyond a certain value if v is the velocity of the wind entering the region and should we not use the velocity of the wind leaving the region kinetic energy of the region will be proportional to the we are out - been the mass of the wind flow rate I'll be calculated a is the area and based on Bernoulli’s principle the product of ted velocity and area entering the decision should be same as that of the diet velocity area product leaving reason this show that that is almost every variable parameter M= Aρv∗v02
P= (1/2) (Aρv∗v02 )(V2-V02
) (4) Cp=((1+(V0/V))(1-(V0/V)2))/2
P=(1/2) (AρVw3Cp) (5) Dating differentiation of same
dP
dx = F = ∂ ρVd (volt )
∂t + ρVdA
M = r ∗ vρV ∗ dA Cp= Power/ AρVw3
Density of seawater may vary from 950 Kg/m3to 1100 Kg/m3 which is very much higher than the wind and creates much higher output. Escape velocity of the system cannot be calculated directly and the best ways to identify the velocity is to identify the output momentum. Newton's second law states that the momentum at any point changes as a result of forces acting on the floor. From the momentum integral equation, the torque developed at the rotor of the turbine as a part from direct deposit from this part. The waves outside the boundary layer of the tunnel has very high Reynolds number where is inside the tunnel has very low Reynolds number. So that will change from the point to point almost in linear manner. Even though a laminar flow is expected that turbine will not have a laminar flow and it will have a disturbed Reynolds numbers. A sudden change in Reynolds numbers create a tension and it may break the tunnel. So the outer periphery has a parabolic structure so as to keep the Reynolds numbers within the limit.
There is ananother law called best limit which states that not more than 50 9.3 % of kinetic energy of input fluent can be extracted and the projected system can have a theoretical efficiency up to 45 %
∂ = (Patm-Pv+ρgh) *Cp / 0.5ρV2
The size and nature of the hydrofoil also have some effect on output. Hydrofoil model is used for this experiment which produce almost 50 % efficiency and is most commonly used. Another problem with such
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high compared to the normal pressure difference. It generates a chance of break of the tunnel. At this part of the tunnel, if the velocity of the wave is very high, there is a chance for break of tunnel. So as to avoid the same, turbine is made with internal auxiliary holes across the periphery of the system with less diameter as less as possible so and the tide water will get out of the same if the pressure goes so high. As the density of water is less than that of air, the bubbles and cavitation will also be eliminated through this holes.
L= 0.5 ρ CLU2 D= 0.5 ρ CdU2
Output of turbine is also depend on the access features of the turbine that the tension force at the lift force of the blade is to be sculpted. The velocity is increased by the length of the blade across the vertical axis. So the lift and drag forces can be calculated so as to design the desired range of diameter. For the time is the axis of rotation water intake, it will create more output and axial level outputs should be in such a way that it does not cross over along the axis, as less then as possible.
IV. REAL-TIME FABRICATION
The projected title tidal power system consist of a wind turbines along with surrounded lens canon tunnel, a generator and other integrated parts. Diffuser is attached to the rotor of the generator so as to increase the speed.
It is used to adjust the speed of the turbine to the desired level and the size of the construction parameters elements in such a way that they will provide maximum efficiency, the system has maximum mechanical strength. The intermediate difference between the blade and diffuser is made to be0.5-3 % of the diameter. The desirable range of a base lens based system model is introduced and it is analyzed using Ansys software.
Optimum possible ranges for various parameters are identified such as using analysis using tide speed,diameter – speed curve, input speed curve , output speed – input speed curve, input speed- turbine speed curve, input speed – speed at lens and all the features of the system parameters are continuously at just so as to get best results. From the analysis, the best optimum result is taken.
An advanced gear changing system is implemented and it will recurrently tuned using a the gear control and cutting-edge converting circuit using a QuaziZetsose converter used and that automatically adjusts the output turbine to consistent to critical speed. The designed system uses a very small 1Kw doubly fed induction generator.
Figure II
V. RESULTS AND DISCUSSIONS
The size of the turbine blade is made to 0.9 meter with a tunnel diameter varies from 1.5meter to 0.5 meter.
Tunnel is of 1 meter long and blade is placed at a diameter of 1 meter.
The Figure III shows the variation of thrust across the tunnel and the blade is placed at a point where thrust is maximum.
Figure III
The velocity profile which describes the variation of the velocity across the tunnel is also shown in Figure IV. It can be found that the velocity is increasing towards the base axis.
Figure IV
Figure V
The relation between angle of attack and coefficient of lift is shown in Figure V. It can be found that as the angle of attack increases, the coefficient of list also increases in directed saturation mode. Still angle of attack cannot be increased beyond a certain value. Angle of attack is made to set from 00 to 360.
Figure VI
The relation between effective radius of tunnel and coefficient of lift is shown in Figure VI. It can be found that as the effective radius of tunnel increases, the coefficient of list also increases initially and then reduces so that it has a parabolic nature. Hence effective radius of tunnel is set between 0.4 – 1 %. Effective radius of tunnel is made to set to 0.15%.
The relation between effective radius of tunnel and speed is shown in Figure VII. It can be found that as the effective radius of tunnel increases, the coefficient of list decreases. Hence effective radius of tunnel is set between set to 0.15%.
Figure VII
The relation between angle of attack and coefficient of lift around the blade section is shown in Figure IX. It can be found that as the angle of attack increases, the coefficient of list also increases. There is a null gap of coefficient of lift about the vertical axis of the blade.
Figure VIII
Figure IX
The relation between Cp and α is shown in Figure V. It can be found that as the Cpincreases, the α also increases in directed saturation mode..
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Figure X
The relation between effective radius of tunnel and angle of attack is shown in Figure VI. It can be found that as the effective radius of tunnel increases, angle of attack decreases. The best range of angle of attack is made to 10% which has more stability.
The velocity profile of the wave across the cross section is analyzed and it is verified that it has a maximum value at the center of the tunnel.
Figure XI
The Real image of the developed prototype is shown in figure XI.
Figure XI
VI. CONCLUSION
The prototype of diffuser tunnel integrated Tidal energy system is designed with regard to the several constraints such as blade dimension, wind speed, mode of diffuser and feature of diffuser. It is found that the system is
much stable for shallow water and slow speed tidal plants. A number of possible models have been analyzed with varying dimensions and features and best mode is selected. The depiction of each prototypical is examined scientifically using Matlab, and the ideal prototype is fabricated. It was found that the proposed system operates up to 20% lesser speed as that of the ordinary model of open type. The effective available output power also increased from 109 - 124 .8 % using the proposed design.
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