volume-09-Issue 1 (2015)
Computational Analysis of Performance and Emissions of a Compression Ignition Engine under various Air Induction Methods
IJTEE, volume-09, Issue 1 (2015) , PP 47 - 52
Published: 25 Dec 2015
by Afaaq Ahmad Mir, M. Marouf Wanib from Research Scholar, NIT Srinagar, India,190006 Faculty of Engineering, NIT Srinagar, India,190006
Abstract: A computational study on performance and exhaust emissions from a 4-stroke DI CI engine using different air induction methods was carried out. Using AVL Boost IC engine simulation software a model was developed with a Naturally Aspirated (NA) air induction mode, the second model was developed by incorporating a turbocharger (TC) and again a third model was developed by the introduction of a turbocharger along with an intercooler (TCI). The individual effects of all the three air induction methods on the performance and emission of engine were studied and compared. The power output for the engine with TCI was observed to be 7.8% more than that of an engine with TC, where as it was even greater i-e 20% more when compared with NA engine. Similar Improved results for torque were also observed in case of an engine with TCI. It was also observed that emissions were higher with TCI followed with TC and NA. read more... read less...
Keywords: Air Induction, Turbo-charging, Inter-cooling, performance, Emissions
Application of Software for the Prediction of Heat Loss in Outdoor Condition during Physical Activity in Nigeria
IJTEE, volume-09, Issue 1 (2015) , PP 41 - 46
Published: 23 Dec 2015
by A. I. Musa, S.O. Ismaila, M.A. Waheed and T.M.A. Olayanju from Mechanical Engineering Department, Moshood Abiola Polytechnic, P.M.B. 2210, Abeokuta, Nigeria 110001 Mechanical Engineering Department, Federal University of Agriculture, P.M.B. 2240, Abeokuta, Nigeria 110001 Agricultural Engineering Department, Federal University of Agriculture, P.M.B. 2240, Abeokuta, Nigeria 110001
Abstract: The human body works to convert energy to provide desired thermal comfort level. This study developed a friendly-user software that is capable of determine and predict correctly the heat loss of a human being working in an outdoor environment. This task was with the use of mathematical model based on the conceptual heat balance equation of the human-environment interaction. There is lacks of computational simulation with user-friendly interfaces to simulating human body physiological responses in outdoor environment reference to the existing outdoor physical and physiological processes mathematical model. This study developed a simulation processes based on the mathematical model reported to determine the heat value, physical sweat rate production and predict the stored energy of human being working in an outdoor environment. This simulation presented was based on the 2nd law of thermodynamics. read more... read less...
Keywords: Outdoor, Human, Software, Energy, Environment, Model, Heat balance.
Feasibility of Using Volcanic Tuff Stone in Ground Heat Exchange for Cooling and Heating Systems in Buildings
IJTEE, volume-09, Issue 1 (2015) , PP 33 - 39
Published: 23 Dec 2015
by Sameh Sqoor, Mohmd Sarireh, Ali Alahmer , Wafa Tarawneh from Department of Mechanical Engineering, Tafila Technical University, P. O. Box 179, 66110 Tafila, Jordan Department of Civil Engineering, Tafila Technical University, P. O. Box 179, 66110 Tafila, Jordan
Abstract: Energy is a crucial sector in Jordan. In the world, Jordan is considered as the highest dependency on foreign energy sources, with 96% of the country's energy imported from oil and natural gas from neighboring countries. Numerically, it consumes 13% from the gross national product (GNP) costing 2.6 billion JD. The need is appearing to use new renewable resources specifically in air conditioning processes to reduce the bill of energy paid annually, in addition to the improve of practices and policies in energy sector. The current research focuses on the use of the ground heat exchange (GHE) model for cooling and heating system to improve the efficiency of the heating, ventilating, and air conditioning (HVAC) units in households and apartments using volcanic tuff stone. A GHE model was constructed by making a hole of 2 m X 1.5 m with a depth of 1.5 m, the volcanic tuff stone is placed enabling heat transfer through volume and voids of stone. The cooled air is extracted by a fan located at the exit (duct 20 X 20 cm) with electric capacity is 60 watts. The temperatures and relative humidity for air inlet and outlet were continuously measured during the period of testing. The results showed that the feasibility of using GHE model as a main part of heating/cooling system. The average temperature difference between the air inlet and exit of GHE model are or cooling and heating system respectively. Also, the relative humidity of air improves reasonably and increases in most cases. read more... read less...
Keywords: Ground heat exchange, energy, HVAC, volcanic tuff, cooling, heating.
Performance Analysis of an Irreversible Regenerative Brayton Cycle Based on Ecological Optimization Criterion
IJTEE, volume-09, Issue 1 (2015) , PP 25 - 32
Published: 23 Dec 2015
by Rajesh Kumara, S. C. Kaushik and Raj Kumar from Department of Mechanical and Automation Engineering, Amity University Haryana, Gurgaon-122413, India b Centre for Energy Studies, Indian Institute of Technology, Delhi, New Delhi-110016, India c Department of Mechanical Engineering, YMCA University of Science & Technology, Faridabad-121006, India
Abstract: An ecological optimization along with a detailed parametric analysis of an irreversible regenerative Brayton cycle with finite heat capacity of external reservoirs have been carried out. The external irreversibilities due to finite temperature difference and internal irreversibilities due to fluid friction losses in compressor / turbine, regenerative heat loss, pressure loss are included in the analysis. Ecological function is thermodynamically optimized which is defined as the power output minus the product of environment temperature and entropy generation rate. A detailed analysis shows that the ecological function and corresponding power output / thermal efficiency can be maximized with judicious selection of parameters such as efficiency of turbine and compressor, effectiveness of various heat exchangers, heat source inlet temperature, pressure drop recovery coefficients and heat capacitance rate of the working fluid. It is found that the regenerative effectiveness is more prominent for maximum ecological function and corresponding thermal efficiency while cold side effectiveness is dominant factor for corresponding power output. It is also found that the effect of turbine efficiency (ηt) is more than the compressor efficiency (ηc) on the thermodynamic performance of an irreversible regenerative Brayton heat engine cycle. The model analyzed in this paper gives lower values of various performance parameters as expected and replicates the results of an irreversible regenerative Brayton cycle model discussed in the literature at pressure recovery coefficients of α1=α2=1. read more... read less...
Keywords: Ecological Criterion, Irreversible Brayton cycle, Regenerator, Power, Efficiency
IJTEE, volume-09, Issue 1 (2015) , PP 17 - 24
Published: 23 Dec 2015
by Sunil J. Kulkarni, Jayant P. Kaware from Department of Chemical Engineering, Datta Meghe College of Engineering, Airoli, Navi Mumbai, India, Bhonsala College of Engineering and Research, Akola, Maharashtra, India
Abstract: In the current research, removal of cadmium from the effluent by using rice husk adsorbent is studied in packed bed with respect to various parameters like initial concentration, adsorbent dose, bed height and pH. Also the solute uptake data was analyzed for first and second order kinetic equations by varying these parameters. The effect of these parameters on kinetics of solute uptake is reported. It was observed that with increase in initial concentration from 10 mg/l to 50 mg/l, the exhaustion time decreased from 830 mg/l to 570 mg/l and break point time decreased from 330 minutes to 120 minutes. Also with increase in flow rate, exhaust time and break through time decreased significantly. The alkaline conditions favoured the adsorption with optimum pH of 6.The exhaustion and break through delayed with increasing bed height. The kinetics of the cadmium removal was affected by initial concentration and flow rate. At low initial concentration, it indicated second order kinetics. There was increasing shift from second to first order with increase in initial concentration. With increase in bed height from 30 to 40 cm there was shift from second to first order but with further increase in bed height, again shift towards second order kinetics was observed. The optimum bed height, initial concentration, flow rate and pH values were 50 cm,30 mg/l, 60 ml/min and 6 respectively. The adsorption efficiency was estimated to be 69 percent for optimum values of pH, initial concentration, bed height and flow rate. read more... read less...
Keywords: adsorbent, break through point, concentration, kinetics.
IJTEE, volume-09, Issue 1 (2015) , PP 7 - 16
Published: 23 Dec 2015
by S.M. Situmbeko, F.L. Inambao from University of KwaZulu-Natal, Durban, South Africa
Abstract: The paper presents work done on the development of a heat exchanger model suitable for incorporation into a low temperature solar thermal power cycle. In particular it presents the mathematical model comprising heat transfer, mass transfer, and convective heat transfer coefficients, and velocity and pressure drop correlations for single and two phase flows. The preliminary evaporator model is based on a counter flow double pipe configuration; the flow boiling process incorporates both convective and nucleate boiling. The shell side heat transfer fluid consists of ethylene glycol at 50 % concentration; the tube side fluid flow is modelled on four candidate working fluids pre-selected from previous stages of the research study. The evaporator model is implemented on the engineering equation solver platform; following on the computer simulation results a further proposal is made for conversion of the model design into a feasible shell-and-tube heat exchanger. The outputs of the model study are in the form of the rate of heat exchange, size and type of the heat exchanger, whilst ensuring that the pressure drops and fluid velocities are within acceptable limits. read more... read less...
Keywords: low temperature solar thermal, convective and nucleate boiling, engineering equation solver.
IJTEE, volume-09, Issue 1 (2015) , PP 1 - 6
Published: 23 Dec 2015
by Merlin Simo Tagne from Douala Higher Institute of Technology, Douala, Cameroon, PO Box 1623
Abstract: In the present paper, a numerical modeling of solar dryer is doing. This solar dryer operates in the natural convection condition and his construction is not difficult because, local materials are used and it is not necessary to follow a particular formation. We have obtained a numerical solution which explains experimental solution. Application is doing on ebony wood that is a wood most difficult to dry and most utilized for the sculpture. With 30mm of thickness, the sample passed 25 days to reduce his water content to 15%, initial water content was equal to 27%, and the drying period is the month of March from the town of Yaoundé, political capital of Cameroon. This modeling proposed is a modest contribution to explain the solar drying of tropical woods at the laboratory scale. read more... read less...
Keywords: Tropical woods, solar drying, modeling, numerical simulation, experiment, diospyros crassiflora.