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Aims and Scope
Editorial Board

1. Analysis of transport phenomena and electrochemical reactions in a micro PEM fuel cell with nature inspired flow field design

Maher A.R. Sadiq Al-Baghdadi

Fuel Cell Research Center, International Energy and Environment Foundation, Najaf, P.O.Box 39, Iraq.

Abstract: Micro-fuel cells are considered as promising electrochemical power sources in portable electronic devices. The presence of microelectromechanical system (MEMS) technology makes it possible to manufacture the miniaturized fuel cell systems. The majority of research on micro-scale fuel cells is aimed at micro-power applications. Performance of micro-fuel cells are closely related to many factors, such as designs and operating conditions. CFD modeling and simulation for heat and mass transport in micro PEM fuel cells are being used extensively in researches and industrial applications to gain better understanding of the fundamental processes and to optimize the micro fuel cell designs before building a prototype for engineering application. In this research, full three-dimensional, non-isothermal computational fluid dynamics model of a micro proton exchange membrane (PEM) fuel cell with nature inspired flow field designs has been developed. The design inspired from the existed biological fluid flow patterns in the leaf. This comprehensive model accounts for the major transport phenomena such as convective and diffusive heat and mass transfer, electrode kinetics, transport and phase-change mechanism of water, and potential fields in a micro PEM fuel cell. The model explains many interacting, complex electrochemical, and transport phenomena that cannot be studied experimentally.

Volume 6, Issue 1, 2015, pp.1-16.

2. Wind energy potential of Marmara region in Turkey

Oktay Arikan¹, Evren Isen², Cagri Kocaman³, Bedri Kekezoglu¹

1 Department of Electrical Engineering, Yildiz Technical University, Esenler, Turkey.

2 Department of Electrical & Electronics Engineering, Kirklareli University, Kirklareli, Turkey.

3 School of Civil Aviation, Ondokuz Mayis University, Samsun, Turkey.

Abstract: Turkey is one of the developing countries in the world. According to economical, industrial and population growth, electrical energy demand has valuably increased in the last decade. The continually increase of electrical energy demand and global sensitivity to environmental pollution raise the importance of renewable energy sources. Wind energy has become more popular than other renewable energy sources owing to its advantages such as supplying great power, being sustainable and clean energy resource. In this study, wind energy potential analysis of Marmara region which is one of the Turkey's geographical regions is presented. Due to its high energy demand, crowded population, large industrial areas and attractive wind energy potential, this paper focused on the Marmara region. Installed wind energy conversion system (WECS) power is 923.65 MW and available WECS power is 46,996.28 MW in Marmara region. It is obviously seen that only 1.96 % of the existent capacity is utilized. A valuable increase in installed capacity could provide an attractive opportunity to decrease the import energy resources, transmission losses and greenhouse gas (GHG) emission of Turkey.

3. The spatial distribution of dust sources in Iraq by using satellite images

Kamal H.Lateef¹, Azhaar K.Mishaal¹, Ahmed M.Abud²

1 Ministry of Science and Technology- Renewable Energy Directorate, Iraq.

2 Ministry of Science and Technology- Environment and Water Directorate, Iraq.

Abstract: Dust storms phenomenon occurs in the most regions of Iraq during the year, this paper is study this phenomenon by using the technique of satellite images, it has been used satellite images (Meteosat-9) with the sensor (SEVERI) and selected different dates of dust storms in 2012, geographic information system programs (ERDAS-GIS) has been used to discrimination the regions that cause this phenomena within the study area to prepare the images to read the real geographic coordinates and determines the regions that caused the occurrence of the dust storms represented by geographical location (Lon/Lat) and making Iraqi map describes these regions for year 2012 and compared with maps for previous years.

4. Decomposition analysis of industry sector CO₂ emissions from fossil fuel combustion in Kazakhstan

Almaz Akhmetov^1,2

1 ENCA Management Ltd., 7 Pobedy Str., Esik, 040400, Kazakhstan.

2 Orizon Consulting, 6481 Elm Str., Suite 161, McLean, VA, USA.

Abstract: The changes in industrial structure of Kazakhstan resulted in significant transformation on its CO₂ emissions profile. Understanding the driving factors in CO₂ emissions profile is essential given the emissions reduction targets committed by Kazakhstan. The study applies Index Decomposition Analysis to identify factors affecting industrial CO₂ emissions caused by fossil fuel combustion for the period 1990-2011. The results of the analysis indicated that the main factor affecting increase in total industrial emissions was the change in the industrial activity, while improvements in energy intensity helped to reduce the emissions. Analysis of six subsectors was used to define the main reasons underlying changes in CO₂ emissions. The study underlines policy contradictions between national plans on expansion of carbon intense commodity based industries and Kazakhstan’s international commitments on CO₂ reduction. Furthermore, the changes in structure of industrial output towards overreliance on commodity based industries and decline of manufacturing could indicate that Kazakhstan is vulnerable to resource curse.

5. Costing energy efficiency improvements in buildings Case study: Braşov, Romania

Elena Eftimie

Department of Product Design, Mechatronics and Environment, Transilvania University of Braşov, Eroilor 29, 500036, Romania.

Abstract: One of the methods of buildings' energetic streamline consists of reducing the thermal energy needs (i.e. the building heating/cooling demand) at the level of building. In this regard, this study provides the opportunity of performing a comparative analysis between the values of energy demand for space heating/cooling, based on a case study in which for a building have been modified, at a time, the insulation material of exterior walls, the thermopane windows and the roof insulation. To evaluate the energy consumption in buildings, it is proposed an advanced hourly calculation method using simulations with TRNSYS program, in order to obtain values as close to reality of the energy demand for their space heating and cooling. It is envisaged that the use of building performance simulation programs allow the modelling and computer simulation of building performance in order to obtain a solution that to approximate to a large extent an actual case. Also it should be noted that the estimation and the analysis of the building energy behaviour – still from the design phase or prior to its rehabilitation – is more efficient and economical than solving problems in the use phase of the building.

6. Exergoeconomic optimization of an irreversible regenerated air refrigerator with constant-temperature heat reservoirs

Yi Zhang¹, Lingeng Chen^2,3,4, Guozhong Chai¹

1 College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, 310014, China.

2 Institute of Thermal Science and Power Engineering, Naval University of Engineering, Wuhan 430033, China.

3 Military Key Laboratory for Naval Ship Power Engineering, Naval University of Engineering, Wuhan 430033, China.

4 College of Power Engineering, Naval University of Engineering, Wuhan 430033, China.

Abstract: Based on the finite time exergoeconomic method, the performance analysis and optimization of an irreversible regenerated air refrigerator cycle are carried out by taking the profit rate as the optimization objective. The profit rate is defined as the difference between the revenue rate of output exergy and the cost rate of input exergy. The analytical expression for profit rate is derived, taking into account several irreversibilities, such as heat resistance, losses due to the pressure drop and the effects of non-isentropic expansion as well as compression. The influences of several parameters such as the temperature ratio of reservoirs, the efficiencies of both compressor and expander, the pressure recovery coefficient and so on are discussed by numerical examples. According to the simulation results, the double-maximum profit rate can be achieved when the pressure ratio and the distributions of heat conductance reach their optimal values respectively. By varying the price ratio, the relationship between the profit rate objective and other objectives can be established and the implementation of profit rate as objective can achieve higher COP compared to the cases using ecological function and cooling load as objectives.

7. Performance analysis of an endoreversible rectangular cycle with heat transfer loss and variable specific heats of working fluid

Chao Wang ^1,2,3, Lingen Chen ^1,2,3,, Yanlin Ge ^1,2,3, Fengrui Sun ^1,2,3

1 Institute of Thermal Science and Power Engineering, Naval University of Engineering, Wuhan 430033, China.

2 Military Key Laboratory for Naval Ship Power Engineering, Naval University of Engineering, Wuhan 430033, China.

3 College of Power Engineering, Naval University of Engineering, Wuhan 430033, China.

Abstract: The performance of an air-standard rectangular cycle with heat transfer loss and variable specific heats of working fluid is analyzed by using finite-time thermodynamics. The relations between the work output and the compression ratio, between the efficiency and the compression ratio, and the optimal relation between work output and the efficiency of the cycle are derived by detailed numerical examples. Moreover, the effects of heat transfer loss and variable specific heats of working fluid on the cycle performance are analyzed. The results show that the effects of heat transfer loss and variable specific heats of working fluid on the cycle performance are obvious. The results may provide some guidelines for the application of the rectangular cycle.

8. Natural convection in a room with two opposite heated vertical walls

Ameer Saad, Abdul Jabbar N. Khalifa

Al-Nahrain University, College of Engineering, Jadiriya, P.O. Box 64040, Baghdad, Iraq.

Abstract: In this study, investigation of radiation and natural convection in cubic enclosure has been carried out. A model of an enclosure representing a room was constructed from polystyrene boards. Two vertical walls are supplied with constant heat flux in the range of 9.4-47.8 W/m². Temperatures of walls, ceiling, floor and air inside enclosure were measured using a 26 K-type thermocouples under steady state condition. Heat transfer was investigated for Rayleigh numbers in the range 4.4E7 -grater equal- Re -less equal-1.2E8 with Prandtl number of 0.71. Detailed results including temperature profiles and correlation equations for convection heat transfer coefficient in terms of temperature difference between the heated surface temperature and the temperature of the air have been obtained for the walls of the enclosure.

9. Analytical performance investigation of parabolic trough solar collector with computed optimum air gap

Devander Kumar¹, Sudhir Kumar²

1 The Technological Institute of Textile & Sciences, Bhiwani, Haryana-127021, India.

2 National Institute of Technology, Kurukshetra, Haryana-136118, India.

Abstract: Parabolic trough collectors have a wide range of industrial as well as domestic applications. This study analytically investigates the performance of non-evacuated absorber tube with glass cover of parabolic trough collector (PTC) in terms of overall heat loss from the absorber. The impact of different parameters such as diameter of absorber tube, mean temperature of absorber tube, wind velocity, emissivity of absorber and ambient temperature have been studied and find the optimum value of air gap. The optimum value of air gap has been computed considering one-dimensional steady state model, where heat loss due to convection plus radiation is equal to heat loss due to conduction plus radiation from absorber tube to glass cover under steady state. Optimum air gap is found to be approximately 7mm and 8 mm for an absorber tube of diameter in range of 1.2-3.18cm and 4.5-7.62cm, respectively. Corresponding to optimum air gap, minimum overall heat loss has been observed. Overall heat loss increases with increase in absorber temperature, wind velocity and emissivity of absorber, whereas decreases with increase in air temperature for different absorber tube diameters. Absorber tube with diameters in the range of 3.18-4.5cm gives better performance. From the obtained data, correlations have been developed, which can be further utilized for designing the PTC system for getting desired output.

10. Najaf, new Saffron homeland

Hashim R. Abdol Hamid

Environment Dept., International Energy and Environment Foundation, Najaf, P.O.Box 39, Iraq.

Abstract: Since its foundation, the International Energy and Environment Foundation (IEEF) interested in improving the situation of the environment in Iraq, where it has several projects and activities in this regard. Among these pilot projects, comes agriculture and indigenization of saffron plant project in Najaf, Iraq. Saffron is a spice derived from the flower of Crocus Sativus, commonly known as the saffron crocus. Crocus is a genus in the family Iridaceae. This project is implemented in two stages: The first stage: Pioneering Agriculture: where is planting limited area and under inspection for the purpose of follow-up agricultural conditions and took the basic data for the stages of plant growth. The second stage: Production Agriculture: where is planting large areas and productive quantities. This project is an important achievement, which is the first of its kind in Iraq in general and in the holy city of Najaf, in particular, where large tracts of land will be invested to cultivate this important and useful plant, and in addition to its commercial benefits, it will contribute stabilize the topsoil and preservation of erosion and improve the climate in the adjacent areas.