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CFD Analysis of Effects of Surface Fouling on Wind Turbine Airfoil Profiles
Sashank Srinivasan,
Vikranth Kumar Surasani
Issue:
Volume 4, Issue 5-1, September 2015
Pages:
1-11
Received:
24 March 2015
Accepted:
11 June 2015
Published:
2 September 2015
DOI:
10.11648/j.ijepe.s.2015040501.11
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Abstract: One of the important factors that determine the long term efficiency of wind turbine blades is the extent to which the surface finish has been altered from the original state. This can happen either through corrosion or through impingement of particles. This paper aims at analyzing the effect of the later phenomenon on two specific profiles: the NREL S814 and NREL S826 profiles, at different Reynold’s numbers. These are two very similar profiles in utility and shape but differ in their thickness. This fact is used to ascertain the effect that thickness of an airfoil has on preventing surface fouling based performance degradation. Surface fouling has been modeled as a roughness at the leading edge of the profile. This is assumed to cause enough flow transition so as to simulate roughness over the entire profile. CFD simulations have been used to perform the analysis and initial results have been validated with experimental data. The accuracy of turbulence models in predicting normal and surface fouled conditions has been assessed. The performance parameters that have been considered are the lift, drag, moment coefficients and the drag to lift ratio.
Abstract: One of the important factors that determine the long term efficiency of wind turbine blades is the extent to which the surface finish has been altered from the original state. This can happen either through corrosion or through impingement of particles. This paper aims at analyzing the effect of the later phenomenon on two specific profiles: the NR...
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Analysis of Lift and Drag Forces at Different Azimuth Angle of Innovative Vertical Axis Wind Turbine
Abhijeet M Malge,
Prashant M Pawar
Issue:
Volume 4, Issue 5-1, September 2015
Pages:
12-16
Received:
24 March 2015
Accepted:
20 August 2015
Published:
2 September 2015
DOI:
10.11648/j.ijepe.s.2015040501.12
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Abstract: Vertical Axis Wind Turbines development was ignored as compared to horizontal axis wind turbines, due to its inability to generate large power. VAWT's have the advantage of working in turbulent wind and at low height. The power generated by VAWT depends upon the drag and lift forces acting on the blades. This paper is focused on analysis of drag and lift forces at different tip speed ratio acting at different azimuth angle of wind turbine. Computational fluid dynamics analysis of turbine is done by using K ω Shear Stress Transportation turbulence model. Computation is done to calculate Drag coefficients, Lift coefficients, and pressure and velocity distribution on wind turbine. Coefficient of lift is maximum at 35 o and minimum at 90 o, drag coefficient is maximum at 60 o and minimum at 150 o, pressure is maximum at 30o and minimum at 90o.
Abstract: Vertical Axis Wind Turbines development was ignored as compared to horizontal axis wind turbines, due to its inability to generate large power. VAWT's have the advantage of working in turbulent wind and at low height. The power generated by VAWT depends upon the drag and lift forces acting on the blades. This paper is focused on analysis of drag an...
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Highly Porous Polymer Electrolytes Based on PVdF-HFP / PEMA with Propylene Carbonate/Diethyl Carbonate for Lithium Battery Applications
P. Sivakumar,
M. Gunasekaran
Issue:
Volume 4, Issue 5-1, September 2015
Pages:
17-21
Received:
25 March 2015
Accepted:
9 June 2015
Published:
2 September 2015
DOI:
10.11648/j.ijepe.s.2015040501.13
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Abstract: The development of new materials is a vital to meet the challenges faced by battery technologies. Ionic conducting solid polymer electrolytes could reduce the risk of explosion with non-flammability and high thermal stability. The use of solid polymer electrolyte is the additional strength of the electrodes performances to increase the number of cycle for the rechargeable batteries. In the present study, preparation of PVdF-HFP/PEMA blend based solid polymer electrolytes enclosure of two different plasticizers such as propylene carbonate (PC) and diethyl carbonate (DEC) at different concentrations and the accumulation of lithium perchlorate as salt. To confirm the structural changes and complex formations, the prepared electrolytes were subjected into XRD and FTIR analyses, and the porous nature of the electrolytes was identified using scanning electron microscopy. AC impedance studies were performed at various temperatures from 303 K to 363K for the prepared samples. The results suggest that the PC/DEC (1:1) based electrolyte exhibited the higher ionic conductivity is 0.00477 S/cm at room temperature and 0.00843 S/cm at 363K. The temperature dependence of ionic conductivity also complies with the VTF relation.
Abstract: The development of new materials is a vital to meet the challenges faced by battery technologies. Ionic conducting solid polymer electrolytes could reduce the risk of explosion with non-flammability and high thermal stability. The use of solid polymer electrolyte is the additional strength of the electrodes performances to increase the number of cy...
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A Review of Technical Issues for Grid Connected Renewable Energy Sources
S. Yasmeena,
G. Tulasiram Das
Issue:
Volume 4, Issue 5-1, September 2015
Pages:
22-32
Received:
25 March 2015
Accepted:
19 August 2015
Published:
2 September 2015
DOI:
10.11648/j.ijepe.s.2015040501.14
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Abstract: Renewable energy in recent years become more and more common, due to the large increase in generation from renewable energy sources such as small hydropower stations, wind turbines, photovoltaic’s (PV) etc. This paper gives the report on two forms of renewable energy wind and solar energy,and on the role of smart grids in addressing the problems associated with the efficient and reliable delivery and use of electricity and with the integration of renewable sources. In this paper different power quality issues are addressed and a FACTS device STATIC COMPENSATOR (STATCOM) is connected at a point of common coupling for grid connected wind turbine to reduce the power quality problems likeharmonics in the grid current, by injecting superior reactive power in to the grid of wind turbine. And also an active power filter implemented with a four leg voltage-source inverter using DQ (Synchronous Reference Frame) based Current Reference Generator scheme is presented for renewable based distributed generation system of PV cell.
Abstract: Renewable energy in recent years become more and more common, due to the large increase in generation from renewable energy sources such as small hydropower stations, wind turbines, photovoltaic’s (PV) etc. This paper gives the report on two forms of renewable energy wind and solar energy,and on the role of smart grids in addressing the problems as...
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Performance of Solar Still with Different Phase Change Materials
Naga Sarada Somanchi,
Anjaneya Prasad B,
Ravi Gugulothu,
Ravi Kumar Nagula,
Sai Phanindra Dinesh K
Issue:
Volume 4, Issue 5-1, September 2015
Pages:
33-37
Received:
28 March 2015
Accepted:
12 June 2015
Published:
2 September 2015
DOI:
10.11648/j.ijepe.s.2015040501.15
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Abstract: Water is basic necessity of man. Fresh water sources are considered to be rivers, lakes and underground water reservoirs. Although, more than two-third of the earth is covered with water and remaining of the earth is land. However, the use of water from such sources is always not good, because of the polluted environment. All over the world, accessing of portable water to the people is narrowing and decreased day by day. Most of the human diseases are due to polluted or un-purified water. Nowadays, each and every country facing a problem of huge water scarcity because of pollution created by manmade activities. Under these circumstances, search for other sources becomes a must. A system is needed which supplies pure water without effecting the ecosystem and environment friendly. Adequate quality and reliability of drinking water supply is a fundamental need of all people on the earth. Fresh water, which was obtained from rivers, lakes and ponds, is becoming scarce because of industrialization and population explosion. The sun is regarded as the source of energy for its constant duration and hygienic state and its remarkable efficiency of not polluting the environment, as other kinds of energy like coal, oil that cause the pollution of atmosphere and environment. Water purification using solar energy has become more popular because it is eco-friendly and cost effective. A solar still is commonly used device for water purification and it doesn’t require any electricity for distillation of water. A variety of solar distillation devices have been developed with different materials and in different shapes in different location to improve the efficiency of solar distillation. This article communicate about the distillation of solar still by using different methods in different areas to improve the efficiency of the solar still.
Abstract: Water is basic necessity of man. Fresh water sources are considered to be rivers, lakes and underground water reservoirs. Although, more than two-third of the earth is covered with water and remaining of the earth is land. However, the use of water from such sources is always not good, because of the polluted environment. All over the world, access...
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Effect of Tail Shapes on Yawing Performance of Micro Wind Turbine
Nikhil C. Raikar,
Sandip A. Kale
Issue:
Volume 4, Issue 5-1, September 2015
Pages:
38-42
Received:
19 August 2015
Accepted:
20 August 2015
Published:
2 September 2015
DOI:
10.11648/j.ijepe.s.2015040501.16
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Abstract: Wind energy is one of the most widely used renewable energy resources. Large amounts of research and resources are being spent today in order to harness the energy from wind effectively. Large wind turbines are erected at windy site and delivering satisfactory performance. Small wind turbines are erected in low wind regions and are in development stage. Research activities are increasing at a significant rate in the field of small wind turbines. World wind energy association forecast considerable development in this field. To face the wind directions, small wind turbines are using mechanical systems in the form of tail. The conventional tail changes the direction of the wind turbine to accommodate the variation of the incoming direction of winds. Quick and steady response is important as per change in wind directions. It has considerable effect on the wind turbine performance. The tails are having different shapes, but literature is not available about it. Different manufacturers used different tail shapes for their model, but the effect of tail shapes has not been studied yet. Hence, it is necessary to study the effect of tail shapes on the performance of wind turbine. This paper presents the effect of tail shapes on the performance of wind turbine. In this work three different tail shapes; rectangular, trapezoidal and triangular are considered. The yawing performance for these tail shapes using CFD analysis is carried out and presented in this paper.
Abstract: Wind energy is one of the most widely used renewable energy resources. Large amounts of research and resources are being spent today in order to harness the energy from wind effectively. Large wind turbines are erected at windy site and delivering satisfactory performance. Small wind turbines are erected in low wind regions and are in development s...
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Optimal Evaluation of Available Transfer Capability of Transmission Line Using Bio-inspired Algorithm for Multiple Transactions in Deregulated Electrical Power Network
Makwana Umesh L.,
Joshi S. K.
Issue:
Volume 4, Issue 5-1, September 2015
Pages:
43-47
Received:
24 March 2015
Accepted:
28 May 2015
Published:
2 September 2015
DOI:
10.11648/j.ijepe.s.2015040501.17
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Abstract: In restructured Electrical Power network the transmission line gets congested by multiple transactions over the line. In such scenario the operator must analyze optimum value of ATC for said transaction. When the transactions between the transmission lines are carried out for a specific destination node/source node pair in a system, the Independent System operator (ISO) must calculate the available transfer capacity (ATC) of that node/source pair. This paper proposes a comprehensive approach to find out the optimized value of ATC for given transaction using Genetic Algorithm. With the help of Genetic algorithm transactions between pair of node can be generated randomly and can be used to calculate optimized value of ATC for each transaction. With the help of this method ISO can declare the value of transacted power from source to destination bus for optimum value of ATC. The objective function is to maximize the power flow capability of transmission line with safest transaction. The solution to the optimization problem gives the amount of accepted requests and available capability of transmission line that could result in a safe and reliable transmission system. The proposed method is applied to an IEEE 30 bus test system.
Abstract: In restructured Electrical Power network the transmission line gets congested by multiple transactions over the line. In such scenario the operator must analyze optimum value of ATC for said transaction. When the transactions between the transmission lines are carried out for a specific destination node/source node pair in a system, the Independent ...
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Development of Transesterification System with Acid and Base Homogeneous Catalysts For Mangifera Indica Seed Oil to Mangifera Indica Methyl Ester (MOME Biodiesel)
Shubhangi S. Nigade,
Sangram D. Jadhav,
Abhimanyu K. Chandgude
Issue:
Volume 4, Issue 5-1, September 2015
Pages:
48-53
Received:
27 March 2015
Accepted:
28 May 2015
Published:
2 September 2015
DOI:
10.11648/j.ijepe.s.2015040501.18
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Abstract: The depletion of resources, increased cost of fossil fuel and increased environmental awareness reaching the critical condition. Development of viable alternative fuels from renewable resources is gaining the international attention and acceptance. The vegetable oils have the potential of alternative fuel for compression ignition engines by converting it into biodiesel. The mangifera indica oil is a nonedible vegetable oil, available in large quantities in mangifera indica cultivating countries including India. Very little research has been done on utilization of oil in general and optimization of transesterification process for biodiesel production. However, direct base catalyzed transesterification produced no biodiesel due to the high Free Fatty Acid ( FFA) value of the oil. Hence, acid pretreatment was preferred prior to base transesterification which afforded a significant reduction of the FFA value from 3.3% to 0.9% . Various input parameters like oil-to-methanol molar ratio (1:08, 1:12 and 1:16), catalyst type (NaOH, KOH and NaOCH3), catalyst concentration (0.5, 1 and 1.5 wt %) and reaction temperature (59, 64 and 69°C) were studied. The optimum conditions for transesterification process are: 1:12 oil-to-methanol molar ratio, 1.0 wt.% catalyst concentration, KOH catalyst, & 64°C reaction temperature. The optimum yield of MOME was 89.8%. The biodiesel produced (MOME) is within the limits prescribed by EN-14214 standard.
Abstract: The depletion of resources, increased cost of fossil fuel and increased environmental awareness reaching the critical condition. Development of viable alternative fuels from renewable resources is gaining the international attention and acceptance. The vegetable oils have the potential of alternative fuel for compression ignition engines by convert...
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Effect of Leading Edge Radius and Blending Distance from Leading Edge on the Aerodynamic Performance of Small Wind Turbine Blade Airfoils
Mahasidha R. Birajdar,
Sandip A. Kale
Issue:
Volume 4, Issue 5-1, September 2015
Pages:
54-58
Received:
31 August 2015
Accepted:
31 August 2015
Published:
7 September 2015
DOI:
10.11648/j.ijepe.s.2015040501.19
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Abstract: The aerodynamic performance of a wind turbine depends upon shape of blade profile blade airfoils. Today, small wind turbine industries are extensively focusing on blade performance, reliability, materials and cost. The wind turbine blade designers are required to give emphasis on accurate analysis of flows around the blade and loads on wind turbine blades. Low Reynolds number airfoils suited for small wind turbine applications must be designed to have a high degree of tolerance in avoiding high leading suction peaks and high adverse pressure gradients that lead to flow separation. This paper presents a study to investigate the effect of leading edge radius and leading edge blending on the aerodynamic performance of wind turbine airfoils. In the present work NACA 4412 airfoil is considered as base airfoils. In this work six modified airfoils having different new to the old ratio of leading edge radii are considered for performance analysis. The performance of these six profiles is compared with basic airfoil performance. In this paper, the effect of blending distance from leading edge of airfoil on aerodynamic performance is also determined. Different five blending distances from leading edge are analyzed and compared with basic profile. The performance analysis of airfoils is carried out using Blade Element Momentum. In the present analysis, chord length of airfoils and Reynolds number are kept constant.
Abstract: The aerodynamic performance of a wind turbine depends upon shape of blade profile blade airfoils. Today, small wind turbine industries are extensively focusing on blade performance, reliability, materials and cost. The wind turbine blade designers are required to give emphasis on accurate analysis of flows around the blade and loads on wind turbine...
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Exploring Next Generation Energy Harvesters with PPE and IDE Electrodes: A Review
Sheetal Agrahari,
Suresh Balpande
Issue:
Volume 4, Issue 5-1, September 2015
Pages:
59-63
Received:
24 March 2015
Accepted:
1 June 2015
Published:
14 September 2015
DOI:
10.11648/j.ijepe.s.2015040501.20
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Abstract: Next generation harvesters promises environment friendly material suitable for medical field also. This paper reviews recent energy harvester for self-powered Microsystems and propose ZnO piezoelectric material for next generation harvesters. In addition to this, Vibration-powered generators are typically subjected to various design related issues which are addressed in this paper.Power can be generated from various environmental sources such as ambient heat, light, acoustic noise, radio waves, and vibration. Piezoelectric based harvester extract energy from the freely available ambient sources i.e. vibration or motion energy. The vibration energy can be converted to electrical energy by the use of piezoelectric PZT, ZnO, AlNGaAs cemented to micro cantilever. Piezoelectric electrodes play a vital role in energy extraction with higher efficiency .Piezoelectric-type harvesters have the highest reported energy density per volume. Furthermore, piezoelectric materials have an inherent capability of converting the mechanical energy into electrical energy, eliminating the need for external magnetic fields, complicated switching systems, and architectural design complexities. In this paper we have reviewed the work carried out by researchers during last few years. This review paper helps to new comers to decide best structure, material and approach to carry out their research work. Results obtained show a good scope for MEMS harvesters in numerous fields including medical field was far away because of poisonous piezoelectric material.
Abstract: Next generation harvesters promises environment friendly material suitable for medical field also. This paper reviews recent energy harvester for self-powered Microsystems and propose ZnO piezoelectric material for next generation harvesters. In addition to this, Vibration-powered generators are typically subjected to various design related issues ...
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