فهرست مطالب

  • Volume:1 Issue:11, 2013
  • تاریخ انتشار: 1391/10/24
  • تعداد عناوین: 9
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  • R. Hassanshahi, M. Fathipour (Ms) Feali Pages 605-610

    TIn the present study, a new structure for the microfluidic fuel cell is proposed to enhance the fuel utilization and the performance of the cell. Using COMSOL Multiphysics software and previously validated numerical model, the impact of the proposed structure on the performance of the cell is investigated. Simulation results show that by increasing electrode surface area through using the new structure, the polarization curve will improve compared with that in the simple microfluidic fuel cell. As a result, the current density increases by nearly 50% and also the power density and fuel utilization improve. It is shown that for the new structure the fuel utilization is 21% for a selected value of the cell voltage (0.5V).

    Keywords: Index Terms, COMSOL Multiphysics, microfluidic fuel cell, the polarization curve, current density, power density, fuel utilization, laminar flow
  • Liliana Cortez, Jose Italo Cortez, Gerardo Mino Aguilar, Selene Maya Rueda, Ana Dominguez Rodriguez, Gregorio Trinidad Garcia, Josefina Castaneda Camacho, Ricardo Alvarez Gonzalez, Alejandro Paredes Camacho, Esteban Herrera Hernandez Pages 611-617

    Energy demand in Mexico has been increasing year after year. Government policy to satisfy this request is to develop alternative energy sources, solar PV, in particular. The use of solar energy implies studying the characteristics of the system, in order to obtain the best possible performance of the intended application. In this paper, an analysis to characterize the efficiency of a photovoltaic system -taking into consideration the features of Mexico, and particularly in the city of Puebla- is developed. In characterizing the efficiency of a photovoltaic system, the environmental effects that have an effect on power generation of a solar photovoltaic system are analyzed.

    Keywords: Index Terms, Simulation, characterization, efficiency, photovoltaic, radiation, temperature
  • Md. Habib Ullah, Tamzidul Hoque (Md) Musaddaqul Hasib Pages 618-627

    Power is one of the most important factors for a developing country like Bangladesh. Like the rest of the countries of the world, the demand for power is increasing day by day in our country. At present, power failure has become an acute problem for this country. In recent times, establishment of important physical infrastructures, setting up of new power plants and the pace of industrialization in the country has slowed down due to energy supply shortage. The sluggish industrialization which has hindered development activities is apprehended to create a negative impact on employment and consequently on the people’s livelihood. Realizing the necessity for its improvement, we proposed grid connected hybrid renewable system in which the load can take power from both the proposed system and grid. In our proposed system, the grid can use the residue power which is left out after the load is supplied completely.

    Keywords: Index Terms, Biogas, Biomass, Gasification, Hybrid system, Solar energy, Wind energy
  • Ripon Kumar Saha, Md.Fashiar Rahamn, Hasan Ali Pages 628-633

    The study focuses on production of biogas as an alternative energy by using biodegradable wastes (BWs) in view of solving waste management at household level. The research was conducted in Laboratory (IEM department), Khulna University of Engineering and Technology (KUET) in 2012.Biogas refers to a gas made from anaerobic digestion of any type of household waste. While any organic material may be a feedstock for anaerobic digestion, waste organic matter represents a vast potential for sustainable energy production. Food waste in particular is a relatively where daily a large amount of kitchen waste is obtained which can be utilized for better purposes. Project was to create an organic processing facility to create biogas which will be more cost effective, eco-friendly, cut down on landfill waste, generate a high quality renewable fuel and reduce carbon dioxide and methane emission. Overall by creating a biogas reactor on campus in the backyard of our halls will be beneficial. Kitchen (food waste) was collected from different halls of KUET as feedstock for our reactor which works as anaerobic digester system to produce biogas energy. The anaerobic digestion of kitchen waste produces biogas, a valuable energy source and about the composition and quantity of constituents in the biogas produced. If biogas technology were adopted throughout the food service industry, this would significantly advance campus and societal sustainability.

    Keywords: Index Terms, Mesophilic Anaerobic Digestion, Kitchen Waste, Biogas, biomethanization, Methanogenesis
  • Reza Keypour, Reza Ilka Pages 635-641

    Permanent magnet synchronous generators (PMSGs) are efficient generators used in so many applications. High efficiency and flexibility in producing electricity from variable rotation make them good candidate for wind power applications. Furthermore, because these kinds of generators are self-excited, they can operate at high power factor. This paper presents design methodology of PMSGs used in small wind turbines. For this purpose all the design equations are provided. Design methodology of PMSGs are complicated, however this paper proposes a simple and comprehensive method for designing such generators which can be extended to the other generators with slight differences. For further clarification, a case study is considered. Finally, results of proposed method are verified with finite element method (FEM) based simulation.

    Keywords: Index Terms, Permanent magnet synchronous generator (PMSG), wind turbines, design methodology, finite element method (FEM), Ansoft Maxwell
  • P.K. Olulope, K.A. Folly Pages 642-648

    The integration of hybrid distributed generation (HDG) is increasing today and the dynamic impact is difference from the single energy source due to differences in dynamic characteristics of the generators involve. Hybrid distributed generation with one or more renewable (stochastic) energy sources interact with the existing grid during import and export of power generation. This interaction contributes difference level of fault current therefore subjecting the system to difference transient instabilities compare to single energy source. This study investigates the dynamic impact of hybrid Wind/ Solar PV/small Hydro power on transient stability. To investigate this impact, a detail modeling of grid connected Wind/ Solar PV and Small hydropower system with single machine infinite system is carried out. The simulation was done in DIgSILENT power factory software. The configuration of the proposed typical grid connected hybrid distributed generation (HDG) consists of Converter Driven Synchronous Generator, Solar PV and Small hydropower system. The wind turbine is integrated through PWM converter into the existing Grid while the solar PV incorporated into the system consists of DC sources integrated through PWM inverter and the hydro power is directly connected through a synchronous generator.

    Keywords: Index Terms, Hybrid distributed generation, stability index, critical clearing time. Wind turbine, Solar PV, Hydropower system, export, import, distributed generation
  • R. Hassanshahi, M. Fathipour Pages 649-654

    This paper reports the performance of a new structure for microfluidic fuel cell. Investigation of the cell operation was conducted by using COMSOL Multiphysics software and employed a previously validated numerical model. Simulation results predict that this new design enhances the polarization curve as compared to the simple microfluidic fuel cell. By tapering the channel both the depletion boundary layer and the mixing region can be controlled; hence, the current density can be increased. This design can increase the current density up to 100%.

    Keywords: Index Terms, COMSOL Multiphysics, microfluidic fuel cell, the polarization curve, current density, laminar flow
  • B. Uma Maheshwari, V. Senthil Kumar Pages 655-657

    WPolycrystalline CZTS thin film has been successfully deposited on the glass substrate using solution growth technique. The combination of X-Ray spectroscopy result and Raman spectrum reveals that thin film shows strong preferential orientation along (112) direction. The grain size has been examined based on XRD pattern. The band gap of CZTS thin film, which is calculated by reflection spectroscopy, has a value of 1.5 eV.

    Keywords: Index Terms, Thin film, Cu2ZnSnS4, chemical coating
  • Muazu. K., Mohammed-Dabo, I.A. Waziri, S.M. Ahmed, A.S., Bugaje, I. M., Ahmad (Ms) Pages 658-665

    The mathematical model for the transestrification of jatropha curcas seed oil was developed by factorial analysis of design of experiment. The factors studied were methanol to oil molar ratio (6 –10), catalyst concentration (4-8wt %), reaction time (1-2hrs) and stirrer speed (100 -700rpm). Analysis of variance (ANOVA) of the experimental results at 95% confidence level revealed that the developed model equation was significant and stirrer speed was the major parameter in the transestrification reaction followed by reaction time and methanol to oil ratio having effects of 24.59, 21.16 and 8.07% respectively. Comparison of experimentally obtained biodiesel yields with the predicted biodiesel yields by the developed model showed close proximity having high correlation coefficient (R2=0.995). Numerical optimization of the process predicted that maximum biodiesel yield of 88.25% would be obtained at the following reaction conditions: methanol to oil molar ratio of 10, catalyst concentration of 8wt%, reaction time of 1 hour and stirrer speed of 700rpm. The developed mathematical model can be employed in simulation of biodiesel production under the reaction conditions studied.

    Keywords: Index Terms, transesterification, jatropha oil, biodiesel, model equation, factorial analysis