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Optimum Geometrical Shape Parameters for Conical Diffusers in Ducted Wind Turbines
Peace-Maker Masukume,
Golden Makaka,
David Tinarwo
Issue:
Volume 5, Issue 6, December 2016
Pages:
177-181
Received:
3 October 2016
Accepted:
17 October 2016
Published:
9 November 2016
DOI:
10.11648/j.ijepe.20160506.11
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Abstract: Encasing of wind turbines in ducts to increase wind energy extraction has been under study for several decades. Ducts are meant to accelerate the wind speed past the wind turbine rotor enclosed in the duct. The most common duct used in wind turbines is a diffuser. Wind speed augmentation in diffusers depends on the geometrical shape parameters of the diffuser, mainly the diffuser expansion angle 
and the non-dimensional length 
. This paper addresses wind speed augmentation by empty conical diffusers. It presents the dependence of the wind speed augmentation on the diffuser geometrical shape parameters and the optimum geometrical shape parameters for maximum wind speed augmentation. It is shown that for a given , wind speed augmentation increases with 
up to the maximum wind speed augmentation and starts to decrease. Each has a unique which gives the maximum wind speed augmentation. It has also been shown that the maximum wind speed augmentation increases with For 
wind speed increased from 1.48 m/s to 1.55 m/s.
Abstract: Encasing of wind turbines in ducts to increase wind energy extraction has been under study for several decades. Ducts are meant to accelerate the wind speed past the wind turbine rotor enclosed in the duct. The most common duct used in wind turbines is a diffuser. Wind speed augmentation in diffusers depends on the geometrical shape parameters of t...
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Modelling and Loading Limits for Kenya Coast Power Network Using Continuation Power Flow
Catherine Nyaguthii Karue,
D. K. Murage,
C. M. Muriithi
Issue:
Volume 5, Issue 6, December 2016
Pages:
182-188
Received:
29 September 2016
Accepted:
18 October 2016
Published:
18 November 2016
DOI:
10.11648/j.ijepe.20160506.12
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Abstract: Shore to ship power connection for docked ship has recently been applied as one way of limiting pollution in ports. This paper studies the effect that a shore to ship connection at the port of Mombasa would have on the voltage stability of the coast region power network. A model of the coast region network is developed and implemented in PSAT. A power flow of the model is used to identify the bus with the highest likelihood of experiencing voltage collapse. Using continuation power flow, the loading limits on this bus are determined. The limits are compared with a load model of the off-shore load to determine the capacity of the existing network to carry the additional load. The paper finds that the existing network has the capacity to carry the extra load. It also recommends contingency actions to mitigate against possible line outages.
Abstract: Shore to ship power connection for docked ship has recently been applied as one way of limiting pollution in ports. This paper studies the effect that a shore to ship connection at the port of Mombasa would have on the voltage stability of the coast region power network. A model of the coast region network is developed and implemented in PSAT. A po...
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The Effect of Well Patterns on Surfactant/Polymer Flooding
Kang Zhou,
Jian Hou,
Xiaoning Li
Issue:
Volume 5, Issue 6, December 2016
Pages:
189-195
Received:
6 December 2016
Published:
7 December 2016
DOI:
10.11648/j.ijepe.20160506.13
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Abstract: Surfactant/polymer flooding enhances oil recovery by increasing water viscosity and decreasing water/oil interfacial tension. Researches have proved that well pattern has a significant effect on the development performance of surfactant/polymer flooding. Based on reservoir numerical simulation method, the paper studies the development performance of surfactant/polymer flooding using line drive well pattern, five-spot well pattern, nine-spot well pattern, inverse nine-spot and inverse seven-spot well pattern. Results show that the line drive method and five-spot method achieve the highest oil recovery while that of the inverse seven-spot well pattern is the lowest. Mechanism analysis indicates that the displacement efficiency is the dominate factor behind the result. So when determining which well pattern should be used for surfactant/polymer flooding, the displacement efficiency have to be increased as much as possible. Besides, the well pattern should be reasonably designed so that the injection and production wells can be perpendicular with the high permeability channels in order to reduce channelling flow of chemicals. When the heterogeneity of an actual large-scale oilfield is strong and complex, several well patterns may be used together.
Abstract: Surfactant/polymer flooding enhances oil recovery by increasing water viscosity and decreasing water/oil interfacial tension. Researches have proved that well pattern has a significant effect on the development performance of surfactant/polymer flooding. Based on reservoir numerical simulation method, the paper studies the development performance o...
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Research on Closed-loop Control System of SEIMENS Class F Gas Turbine
Issue:
Volume 5, Issue 6, December 2016
Pages:
196-202
Received:
24 December 2016
Published:
28 December 2016
DOI:
10.11648/j.ijepe.20160506.14
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Abstract: Gas Turbine engine is the most advanced large equipment in the world; the automatic control is a very important matter. The closed-loop is the core of automatic control, and it is also the most complex. Jing Neng Gaoantun gas power plant installed Siemens’ SGT5-4000F gas turbine. As a typical model of Class F gas turbine, closed-loop followed many classical designs of Siemens. As a technical stuff in this industry, we have to know the strategy and principle of the Closed-loop Control System, thus we can analyze and diagnosis operation better.
Abstract: Gas Turbine engine is the most advanced large equipment in the world; the automatic control is a very important matter. The closed-loop is the core of automatic control, and it is also the most complex. Jing Neng Gaoantun gas power plant installed Siemens’ SGT5-4000F gas turbine. As a typical model of Class F gas turbine, closed-loop followed many ...
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Ionic Liquid as Electrolyte in Photogalvanic Cell for Solar Energy Conversion and Storage
Sawsan A. Mahmoud,
Basma S. Mohamed,
Mamdouh Doheim
Issue:
Volume 5, Issue 6, December 2016
Pages:
203-208
Received:
20 November 2016
Accepted:
10 December 2016
Published:
9 January 2017
DOI:
10.11648/j.ijepe.20160506.15
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Abstract: 1-Butyl-3-methylpyridinium bis(trifluoromethylsulfonyl)imide ([c43mpy] [NTf2]) ionic liquid was used as electrolyte in photogalvanic cell. For photo-electrochemical conversion of solar energy to electrical energy, Rose Bengal, oxalic acid and ([c43mpy] [NTf2]) was used as a novel system. The photopotential and photocurrent was 670.0 mV and 61.2 µA, respectively. The power of the cell at power point was 8.06 µW. The low values of the electrical output could be attributed to the fast mobility of the cation and aggregation motives. There are also several reasons related to the structure of the ionic liquid. The observed conversion efficiency was 0.077% and fill factor was 0.196. The storage capacity of the cell was 109.0 min. The effect of different factors affecting on electrical output of the cell was studied.
Abstract: 1-Butyl-3-methylpyridinium bis(trifluoromethylsulfonyl)imide ([c43mpy] [NTf2]) ionic liquid was used as electrolyte in photogalvanic cell. For photo-electrochemical conversion of solar energy to electrical energy, Rose Bengal, oxalic acid and ([c43mpy] [NTf2]) was used as a novel system. The photopotential and photocurrent was 670.0 mV and 61.2 µA,...
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Direct Ethanol Fuel Cell (DEFC) Assembled with Ceramic Membrane-Catalyst
Back-Sub Sung,
Young-Hoon Yun
Issue:
Volume 5, Issue 6, December 2016
Pages:
209-214
Received:
7 November 2016
Accepted:
12 December 2016
Published:
10 January 2017
DOI:
10.11648/j.ijepe.20160506.16
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Abstract: Direct ethanol fuel cell (DEFC) has been assembled with the ceramic membrane based-Pt/C (40wt%) catalyst electrodes. The porous silicon carbide (SiC) membrane, fabricated through sintering process, was applied for the fabrication of DEFC. The dilute ethanol-water fuel solution was used for the DEFC operation with a micropump and air blower. The direct ethanol oxidation based-ceramic membrane fuel cell showed relatively stable potential-current behavior even though at room temperature by a continuous air-blowing and a circulation of the dilute-ethanol fuel solution. The other chemicals such as acetaldehyde or acetic acid, being formed during DEFC operation, was not detected from the NMR (nuclear magnetic resonance) spectrum analyzed with the dilute ethanol fuel solution collected upto 90min.
Abstract: Direct ethanol fuel cell (DEFC) has been assembled with the ceramic membrane based-Pt/C (40wt%) catalyst electrodes. The porous silicon carbide (SiC) membrane, fabricated through sintering process, was applied for the fabrication of DEFC. The dilute ethanol-water fuel solution was used for the DEFC operation with a micropump and air blower. The dir...
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A Review on Recent Development of Photovoltaics and Wind Turbines
Muhyaddin J. H. Rawa,
David W. P. Thomas,
Mark Sumner
Issue:
Volume 5, Issue 6, December 2016
Pages:
222-227
Received:
20 October 2016
Accepted:
19 December 2016
Published:
18 January 2017
DOI:
10.11648/j.ijepe.20160506.18
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Abstract: Recently, Renewable Energy Resources (RERs) are becoming increasingly more employed for energy generation due to the advancement in power electronics industry, the environmental and economic challenges being faced by the world. Among these RERs are the Photovoltaics (PVs) and Wind Turbines (WTs). The aim of this paper is to discuss the recent development of both PVs and WTs. the figures considered the global development. The figures are obtained from international and local agencies, councils and associations.
Abstract: Recently, Renewable Energy Resources (RERs) are becoming increasingly more employed for energy generation due to the advancement in power electronics industry, the environmental and economic challenges being faced by the world. Among these RERs are the Photovoltaics (PVs) and Wind Turbines (WTs). The aim of this paper is to discuss the recent devel...
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