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Aims and Scope
Editorial Board

1. Exergoeconomic performance optimization of an endoreversible intercooled regenerated Brayton cogeneration plant. Part 1: Thermodynamic model and parameter analyses

Lingen Chen, Bo Yang, Fengrui Sun

Postgraduate School, Naval University of Engineering, Wuhan 430033, P. R. China.

Abstract: A thermodynamic model of an endoreversible intercooled regenerative Brayton heat and power cogeneration plant coupled to constant-temperature heat reservoirs is established by using finite time thermodynamics in Part 1 of this paper. The heat resistance losses in the hot-, cold- and consumer-side heat exchangers, the intercooler and the regenerator are taken into account. The finite time exergoeconomic performance of the cogeneration plant is investigated. The analytical formulae about dimensionless profit rate and exergetic efficiency are derived. The numerical examples show that there exists an optimal value of intercooling pressure ratio which leads to an optimal value of dimensionless profit rate for the fixed total pressure ratio. There also exists an optimal total pressure ratio which leads to a maximum profit rate for the variable total pressure ratio. The effects of intercooling, regeneration and the ratio of the hot-side heat reservoir temperature to environment temperature on dimensionless profit rate and the corresponding exergetic efficiency are analyzed. At last, it is found that there exists an optimal consumer-side temperature which leads to a double-maximum dimensionless profit rate. The profit rate of the model cycle is optimized by optimal allocation of the heat conductance of the heat exchangers in Part 2 of this paper.

Volume 2, Issue 2, 2011, pp.199-210.

2. Exergoeconomic performance optimization of an endoreversible intercooled regenerated Brayton cogeneration plant. Part 2: Heat conductance allocation and pressure ratio optimization

Bo Yang, Lingen Chen, Fengrui Sun

Postgraduate School, Naval University of Engineering, Wuhan 430033, P. R. China.

Abstract: Finite time exergoeconomic performance of an endoreversible intercooled regenerative Brayton cogeneration plant is optimized based on the model which is established using finite time thermodynamic in Part 1 of this paper. It is found that the optimal heat conductance allocation of the regenerator is zero. When the total pressure ratio and the heat conductance allocation of the regenerator are fixed, it is shown that there exist an optimal intercooling pressure ratio, and a group of optimal heat conductance allocations among the hot-, cold- and consumer-side heat exchangers and the intercooler, which correspond to a maximum dimensionless profit rate. When the total pressure ratio is variable, there exists an optimal total pressure ratio which corresponds to a double-maximum dimensionless profit rate, and the corresponding exergetic efficiency is obtained. The effects of the total heat exchanger conductance, price ratios and the consumer-side temperature on the double-maximum dimensionless profit rate and the corresponding exergetic efficiency are discussed. It is found that there exists an optimal consumer-side temperature which corresponds to a thrice-maximum dimensionless profit rate.

3. Thermodynamic analysis of gas – steam combined cycle with carbon dioxide (CO₂) emissions saving

Alka Gupta, Om Prakash, S.K. Shukla

Department of Mechanical Engineering, Institute of Technology Banaras Hindu University, Varanasi - 221005, India.

Abstract: In this paper, cogeneration or combined heat and power (CHP) cycle has been analyzed in order to improve the efficiency of the gas – steam combined cycle and utilization of waste heat. The efficiency of the combined cycle is improved by decreasing the compressor inlet temperature (CIT) and increasing the turbine inlet temperature (TIT). It is observed that the cycle offers the advantage of making efficient use of the energy available in the fuel and in turn, eliminate some portion of pollution associated with the power generation. The study also reveals that if this cycle is being employed for cogeneration, there is a significant saving (11.60%) in the amount of Carbon dioxide (CO₂) emitted by the coal-fired thermal power plants.

4. Spectral analysis of total ozone column variability using TOMS data over Baghdad, Iraq

Ali M. AL-Salihi

Department of Atmospheric Sciences, College of Science, AL-Mustansiriyah University, Baghdad, Iraq.

Abstract: Total Ozone Column (TOC) measured by Total Ozone Mapping Spectrometer (TOMS) broad on Earth probe (EP) for Baghdad city (Lat 33.35 N^o, Long 44.45 E^o) has been analyzed. The results give the estimate means and variability of temporal scale. Using linear regression, results shows that TOC has a trend of – 0.333 DU per year. The maximum and minimum day to day variation of TOC were 40.9% (121DU) and 22.4%(-66.3DU) respectively. A spectral analysis on daily values shows that the dominating oscillation periods are between 2.8 and 5.4 days. Solar activity has a weak effect on total ozone production with correlation coefficient (0.22).

5. Knowledge based expert system to minimise environmental pollution in Malaysian construction sites

Ibrahiem Abdul Razak Al-Hadu¹, Lariyah Mohd Sidek¹, Mohamad Nor Mohamad Desa¹, Noor Ezlin Ahmad Basri²

1 Civil Engineering, Universiti Tenaga Nasional, Kajang, Selangor, Malaysia.

2 Civil and Structural Engineering, Universiti Kebangsaan Malaysia, Bangi, Selangor, Malaysia.

Abstract: Construction activities generate enormous amount of erosion and sediments sediments that is the result of soil disturbance during construction activities, thus, will pollute the adjacent water bodies and make it unfeasible for different uses. This paper aimed to develop and create the main features of an expert system prototype (ESCES) for minimising erosion and sedimentation due to stormwater generated from the construction activities by recommending a feasible BMPs. Multi criteria Analysis (MCA) technique has been integrated so as to select the best control measure among many stormwater control alternatives. A questionnaire has been distributed to the relevant experts so as to rank the stormwater control measures to be used in the MCA technique. Using Visual Basic 6, Graphical User Interfaces (GUIs) were developed. The knowledge and experience were acquired from various textural sources (i.e. guidelines, manuals, literature, and human expert). Results from this study showed that the Best Management Practices (BMPs) reommended have good suited the site characteristics. As a conclusion from this study, the ESCES can be considered as part of the “Green Technology Tool” since it helps in protecting the environment and preserve good quality of water adjacent to the construction sites in Malaysia.

6. Analysis and performance of high efficiency synchronous reluctance machines

M. Nagrial, J. Rizk, A.Hellany

University of Western Sydney, School of Engineering, Power Conversion and Intelligent Motion Control Group, Locked Bag 1797, Penrith South DC, Australia.

Abstract: A series of new solid rotor reluctance machines have been proposed to achieve high saliency ratio. It is shown that proper distribution of magnetic and non-magnetic materials can result in improved performance. The saliency ratios and configurations of experimental machines are also given. The solid rotor design is attractive from manufacturing point of view. The paper discusses the analysis, performance and design aspects of reluctance motors. The design and performance of a series of experimental machines is also given.

7. An overview of global solar radiation measurements in Ghardaia area, south Algeria

Kacem Gairaa, Yahia Bakelli

Applied Research Unit for Renewables Energies, Ouargla road, Ghardaia, Algeria.

Abstract: This paper presents an overview of actual solar radiation data measurements in Ghardaia site (32.360 N, 3.810 W, 450 m above MSL). Global solar radiation and surface temperatures were measured and analyzed for one complete year from 1 January-31December 2005. The data thus recorded are compared with corresponding data of the 22-year average of NASA's surface meteorology and solar energy-model. Hourly, daily and monthly solar radiation was made from five-minute recorded by EKO Pyranometer. The highest measured daily and monthly mean solar radiation was found to be 369 and 326 (W/m2), and the highest five minute averaged solar radiation values up to 1268 (W/m²) were observed in the summer season from May to September, and the yearly average daily energy input was 21.83 (MJ/m²/day). Besides the global solar radiation, the daily and monthly average temperature variations are discussed. The collected data indicate that Ghardaia has a strong potential for solar energy applications.

8. Building thermal performance in Saharan climate

Brahim BELGAID

Department of architecture, University of Batna, 05000- Batna, Algeria.

Abstract: The aim of this study is to present an analytical method of the contribution of the building’s shape and orientation in the definition of a comfortable microclimate for the inhabitants of the warm regions of Algerian Sahara. Study is made by using the overheating, a concept allowing a fast estimation of the level of internal temperature. Calculations were performed for summer hot period for Biskra (a city of southern Algeria), situated in Sahara and characterized with a hot and dry climate. The influence of the shape and the orientation of the building are examined as a solution to improve the building’s thermal performance.

9. Microgrids: Energy management by loss minimization technique

A. K. Basu¹, S. Chowdhury², S.P. Chowdhury²

1 Electrical Engineering Dept., Jadavpur University & 20/2, Khanpur Road, Kolkata 700047, India.

2 Electrical Engineering Department, University of Cape Town & Private Bag X3, Menzies Building, Room-517, Rondebosch, Cape Town 7701, India.

Abstract: Energy management is a techno-economic issue, which dictates, in the context of microgrids, how optimal investment in technology front could bring optimal power quality and reliability (PQR) of supply to the consumers. Investment in distributed energy resources (DERs), with their connection to the utility grid at optimal locations and with optimal sizes, saves energy in the form of line loss reduction. Line loss reduction is the indirect benefit to the microgrid owner who may recover it as an incentive from utility. The present paper focuses on planning of optimal siting and sizing of DERs based on minimization of line loss. Optimal siting is done, here, on the loss sensitivity index (LSI) method and optimal sizing by differential evolution (DE) algorithms, which is, again, compared with particle swarm optimization (PSO) technique. Studies are conducted on 6-bus and 14-bus radial networks under islanded mode of operation with electric demand profile. Islanding helps planning of DER capacity of microgrid, which is self-sufficient to cater its own consumers without utility’s support.

10. Feasibility of a solar-assisted winter air-conditioning system using evaporative air-coolers

Mohamed M. El-Awad

Mechanical Engineering Department, the University of Khartoum, P.O. Box 321 Khartoum, Sudan.

Abstract: The paper presents a winter air-conditioning system which is suitable for regions with mildly cold but dry winters. The system modifies the evaporative air-cooler that is commonly used for summer air-conditioning in such regions by adding a heating process after the humidification process. The paper describes a theoretical model that is used to estimate the system's water and energy consumption. It is shown that a 150-LPD solar heater is adequate for air-conditioning a 500 ft3/min (14.4 m3/min) air flow rate for four hours of operation. The maximum air-flow rate that can be heated by a single solar water-heater for four hours of operation is about 900-cfm, unless a solar water heater large than a 250-LPD heater is used. For the 500 ft3/min air flow rate the paper shows that the 150, 200, 250 and 300 LPD solar water-heaters can provide air-conditioning for 4, 6, 8 and 10 hours, respectively, while consuming less energy than the equivalent refrigerated-type air-conditioner.

11. Experimental investigation of heat transfer and friction factor in a corrugated plate heat exchanger

Shive Dayal Pandey, V.K. Nema

Department of Mechanical Engineering, MNNIT, Allahabad-211004 (U.P), India.

Abstract: Experiments are conducted to determine the heat transfer characteristics for fully developed flow of air and water flowing in alternate corrugated ducts with an inter-wall spacing equal to the corrugation height. The friction factor is found for air channel. The test section was formed by three identical corrugated channels having corrugation angle of 30^o with cold air flowing in the middle one and hot water equally divided in the adjacent channels. Sinusoidal wavy arcs connected with tangential flat portions make the said corrugation angle with transverse direction. The Reynolds number based on hydraulic diameter varied from 750 to 3200 for water and from 16900 to 68000 for air by changing the mass flow rates of the two fluids. The Prandtl numbers were approximately constant at 2.55 for water and 0.7 for air. The various correlations are obtained Num=0.247Re0.83 for water, Num=66.686Re0.18 and friction factor f = 0.644 / Re0.18 for air.

12. Comparative performance study of vapour compression refrigeration system with R22/R134a/R410A/R407C/M20

Vaibhav Jain¹, S. S. Kachhwaha², R. S. Mishra²

1 Mechanical and Automation Engineering Department, GPMCE, Delhi, India.

2 Mechanical Engineering Department, DTU, Delhi, India.

Abstract: Several refrigerants have emerged as substitutes to replace R22, the most widely used fluorocarbon refrigerants in the world. These include the environmentally –friendly hydrocarbon (HFC) refrigerants R134a, R410A, R407C and M20. In the present research study a refrigerant property dependent thermodynamic model of a simple reciprocating system, which can simulate the performance of actual system as closely as possible, has been used to compare the characteristics of various refrigerants [R22, R134a, R410A, R407C and M20] used by world manufacturers to meet the challenges of higher efficiency and environmental responsibility while keeping their system affordable. Considering the recent trends of replacement of ozone depleting refrigerants and improvement in system efficiency, in the present study, R407C can be a potential HFC refrigerant replacement for new and existing systems presently using R22 with minimum investment and efforts.

13. A review on granules initiation and development inside UASB Reactor and the main factors affecting granules formation process

S. A. Habeeb, AB. Aziz Bin Abdul Latiff, Zawawi Bin Daud, Zulkifli Bin Ahmad

Faculty of Civil and Environmental Engineering, University Tun Hussein Onn Malaysia (UTHM).

Abstract: Decades of investigations and explorations in the field of anaerobic wastewater treatment have resulted in significant indications about the role importance of sludge granules in biodegradation anaerobic process. It is believed that the development of anaerobic granules is reflecting an important role on the performance of reactor. An overview on the concept of up-flow anaerobic sludge bed UASB reactor operation as well as the main parts that reactor consists of is briefly explained in this paper, whereas the major theories of anaerobic granules formation are listed by related researchers. The correlations and compositions of such sludge granule have been specifically explained. It is believed that the extracellular polymer (ECP) is totally responsible of bacterial cell correlations and the formation of bacterial communities in the form of granules. In addition, the dependable factors for the performance of anaerobic granules formation process e.g. temperature, organic loading rate, pH, and alkalinity, nutrients, and cations and heavy metals have been discussed in this paper. Strong evidences proved that the process of gas production in the form of biogas is related to the methanogens activities, which are practically found in the core of granules. The aim of this review is to explore and assess the mechanisms of granules initiation and development inside UASB reactor.

14. Effect of diesel addition on the performance of cottonseed oil fuelled DI diesel engine

Leenus Jesu Martin. M¹, Edwin Geo. V², Prithviraj. D³

1 Department of Automobile Engineering, SRM University, Chennai-603203, India.

2 Department of Mechanical Engineering, GKM College of Engineering and Technology, Chennai-600063, India.

3 Department of Mechanical Engineering, SRM University, Chennai-603203, India.

Abstract: In this investigation the viscosity of cottonseed oil, which has been considered as an alternative fuel for the compression Ignition (C.I) engine was decreased by blending with diesel. The blends of varying proportions of cottonseed oil and diesel were prepared, analyzed and compared with the performance of diesel fuel and studied using a single cylinder C.I. engine. Significant improvement in engine performance was observed compared to neat cottonseed oil as a fuel. The brake thermal efficiency, specific fuel consumption, volumetric efficiency, peak cylinder pressure, smoke, CO, HC, NO and the exhaust gas temperatures were analyzed. The tests showed increase in the brake thermal efficiencies of the engine as the amount of diesel in the blend increased. The volumetric efficiency of the engine also increased when compared with that of neat cottonseed oil and the exhaust gas temperature with the blends decreased. The smoke, CO and HC emissions of the engine ware also less with the blends. From the engine test results it has been established that 20–40% of cottonseed oil can be substituted for diesel without any engine modification as a fuel.

15. First performance assessment of blends of jatropha, palm oil and soya bean biodiesel with kerosene as fuel for domestic purposes in rural-Ghana

Quansah E., K. Preko, L. K. Amekudzi

Department of Physics, Kwame Nkrumah, University of Science and Technology (KNUST), University Post Office, PMB Kumasi, Ghana.

Abstract: Performance assessments of jatropha, palm oil and soya bean based biodiesel were carried out to investigate their potential use as conventional substitute for kerosene for domestic purposes in rural- Ghana. The assessments were done by comparing some of the combustion characteristics of blends of the biodiesel with kerosene. The blends were categorised as B100 (100% biodiesel), B80 (80% biodiesel and 20% kerosene), B60 (60% biodiesel and 40% kerosene), B40 (40% biodiesel and 60% kerosene), B20 (20% biodiesel and 80% kerosene) and B0 (pure kerosene). The results showed that the calorific values of the B100s were less than that of the B0 and decreasing in the order of jatropha, soya bean and palm oil. The wick wastage results for both the B100s and B0, revealed higher rates in the WTL than the BB even though the BB recorded low fuel consumption rates than the WTL for both B100s and B0. Similarly, the luminous intensity test with the B100s showed low values in WTL than the BB in a decreasing order of jatropha, soya bean and palm oil. However, B0 recorded higher luminous intensity values that were quite comparable in both WTL and BB.

16. Performance of advanced photocatalytic detoxification of municipal wastewater under solar radiation - A mini review

Chandan Singh, Rubina Chaudhary, Rajendra Singh Thakur

School Of Energy and Environmental Studies, Devi Ahilya University, Takshashila Campus, Khandwa Road, Indore-452001, M.P., India.

Abstract: During the last few years, there has been a plethora of research and development in the area of solar photocatalysis. The aim is to understand the fundamental processes and enhance photocatalytic efficiencies especially for air, soil and water pollution control. Municipal waste water is limited by continual organic water pollutants and micro-organisms that are not removed by conventional mechanical and biological treatment. In this overview of the most recent paper, studies focused on the treatment of municipal wastewater (containing organic compounds) by photocatalysis and the effects of various parameters such as pH, light intensity, Advance oxidation method etc. have been studied It can be concluded that the photocatalysis process is suitable for the treatment of drinking water, municipal and industrial wastewater. Some studies on the economic analysis of photocatalytic systems are also included.

17. Studies of base catalyzed transesterification of karanja oil

Naveenji Arun, Muthukumaran Sampath, S.Siddharth, Prasaanth R.A

Department of Chemical Engineering, Sri Venkateswara College of Engineering, Pennalur, Chennai-602105, India.

Abstract: Karanja oil methyl ester was synthesized by the transesterification of karanja oil with methanol using potassium hydroxide as catalyst. The reaction was carried out at 55°C for 1 hour. The reactants were continuously stirred with speed ranging from 250-650 rpm. The acid value of oil was found to be 18.62 mg KOH/g of oil. Influence of parameters like water content (%), oil flow rate (ml/min) and effect of stirring speed (rpm) were investigated by varying these parameters in 5 levels and a design for performing the experiments was developed using Minitab and Design-Expert. An approach has been made to study the pressure and velocity changes when the reactants flow through the inlet and outlet pipes. Glycerol being insoluble remained in the reactor and the conversion was found by testing the ester using Gas Chromatography and also by analyzing the acidity of the samples.

18. Vehicle gearbox fault diagnosis using noise measurements

Sameh M. Metwalley, Nabil Hammad, Shawki A. Abouel-Seoud

Faculty of Engineering, Helwan University, Cairo, Egypt.

Abstract: Noise measurement is one of many technologies for health monitoring and diagnosis of rotating machines such as gearboxes. Although  significant research has been undertaken  in understanding the potential of noise measurement  in monitoring gearboxes this has been solely applied on any types of gears (spur, helical, ..etc.). The condition monitoring of a lab-scale, single stage, gearbox, represents the vehicle real gearbox, using non-destructive inspection methodology and the processing of the acquired waveform with advanced signal processing techniques is the aim of the present work. Acoustic emission was utilized for this purpose. The experimental setup and the instrumentation are present in detail. Emphasis is given on the signal processing of the acquired noise measurement signal in order to extract conventional as well as novel parameters potential diagnostic value from the monitoring waveform. The evolution of selected parameters/features versus test time is provided, evaluated and the parameters with most interesting diagnostic behavior are highlighted. The present work also reports  the results concluded by long term (~ 6.0 h) experiments to a defected gear system, with a transverse cuts ranged from 0.75 mm to 3.0 mm to simulate the tooth crack. Different parameters, related by the analysis of the recording signals coming from acoustic emission are presented and their diagnostic value is discussed for the development of a condition monitoring system.

19. Performance analysis of porous radiant burners used in LPG cooking stove

P. Muthukumar, Piyush Anand, Prateek Sachdeva

Department of Mechanical Engineering, Indian Institute of Technology Guwahati, Guwahati – 781039, India.

Abstract: This paper discusses the performance investigations of a porous radiant burner (PRB) used in LPG cooking stove. Performance of the burner was studied at different equivalence ratios and power intensities. Thermal efficiency was found using the water-boiling test described in IS: 4246:2002. The newly designed PRB showed a maximum thermal efficiency of about  71%, which is 6% higher than that of the conventional burners. Influence of ambient temperature on the thermal efficiency of the PRB was also investigated. Using a PRB of 80 mm diameter at the operating conditions of 0.68 equivalence ratio and 1.24 kW power intensity, the thermal efficiency was found to increase from 61% at 18.5 oC to 71% at 31 oC ambient temperature. The CO and NOx emissions of the PRB are in the range of 9 to 16 ppm and 0 to 0.2 ppm, respectively, while the respective values for the conventional burner are in the range of 50 to 225 ppm and 2 to 7 ppm.

20. Effect of heat source and variable suction on unsteady viscous stratified flow past a vertical porous flat moving plate in the slip flow regime

S. S. Das¹, M. Maity², J. K. DAS³

1 Department of Physics, KBDAV College, Nirakarpur, Khurda-752 019 (Orissa), India.

2 Department of Physics, Suddhananda Residential Polytechnic, Bhatapatna, Phulnakhara, Cuttack- 752 115 (Orissa), India.

3 Department of Physics, Stewart Science College, Mission Road, Cuttack-753 001(Orissa), India.

Abstract: This paper investigates the effect of heat source and variable suction on unsteady viscous stratified flow through a porous medium due to a moving porous plate under slip boundary condition for velocity field and jump in temperature field. The velocity of the porous plate decreases exponentially with time about a constant mean and a variable suction velocity is applied normal to the plate. The governing equations of the flow field are solved using perturbation technique and the expressions for velocity field, temperature distribution, skin-friction and heat flux are obtained. The effects of the pertinent parameters such as permeability parameter (Kp), velocity slip and temperature jump parameter (h1, h2), stratification parameter (alpha), suction velocity parameter (A), the heat source parameter (S) and Prandtl number (Pr) on velocity and temperature distribution of the flow field and also on skin-friction and the rate of heat transfer are analyzed and discussed with the aid of figures and table.

21. Effect of orange peel oil addition on the performance of cottonseed oil fuelled DI diesel engine

Leenus Jesu Martin. M¹, Edwin Geo. V², Prithviraj. D³

1 Department of Automobile Engineering, SRM University, Chennai-603203, India.

2 Department of Mechanical Engineering, GKM College of Engineering and Technology, Chennai-600063, India.

3 Department of Mechanical Engineering, SRM University, Chennai-603203, India.

Abstract: The world petroleum situation due to rapid depletion of fossil fuels and the degradation of the environment due to the combustion of fossil fuels have caused a resurgence of interest in finding alternative fuel. Vegetable oil based fuels are biodegradable, non-toxic and significantly reduce pollution. Cottonseed oil, which is considered, is not suitable as a fuel for diesel engines straight because of its high viscosity. Addition of a small quantity of another light vegetable oil, Orange Peel oil reduces the viscosity and improves the performance of the engine largely. Blends of varying proportions of cottonseed oil and orange peel oil were prepared, analyzed and their properties were calculated. The performance of the engine using diesel, the blends and cottonseed oil were evaluated using a single cylinder, four stroke, direct injection compression ignition engine. The results obtained were compared with baseline data generated with raw cottonseed oil and diesel. 15% of Orange peel oil by volume addition to cottonseed oil exhibited the best performance and smooth engine operation with out any problem.