iosr-JMCE   Volume-6 ~ Issue-2

Paper Type	:	Research Paper
Title	:	The CFD Analysis of Turbulence Characteristics in Combustion Chamber with Non Circular Co-Axial Jets
Country	:	India
Authors	:	N L Narasimha Reddy, P Manivannan, K M Kiran Babu
	:	10.9790/1684-0620110

Abstract: Co-Axial jets have applications in areas where the mixing of two fluid jets are necessary, the two fluid jets can be effectively mixed by producing the turbulence flow. Turbulence is a chaotic behavior of the fluid particles that comes in to picture when the inertia force of the flow dominates the viscous force and it is characterized by the Reynolds Number. Co-axial jets are effective in producing the turbulence. In the present study the free compressible turbulent coaxial jet problem will be computed using CFD, and compare with different non circular coaxial jets based on constant hydraulic diameter and mass flow rate. Turbulence characteristics of combustion chamber with circular coaxial and non circular coaxial jets are determined and compared.

Keywords: Coaxial Jet, Turbulence Modeling, Fuel injector, Combustion chamber.

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Paper Type	:	Research Paper
Title	:	CFD Simulation of Swirling Effect in S-Shaped Diffusing Duct by Swirl Angle of 10˚
Country	:	India
Authors	:	Ramazan, Jawaz Pasha, Abdul Mujeeb M S
	:	10.9790/1684-0621119

Abstract: The present study involves the CFD analysis for the prediction of swirl effect on the characteristics of a steady, incompressible flow through an S-shaped diffusing duct BY KEEPING SWIRL ANGLE OF 10˚. The curved diffuser considered in the present case has S-shaped diffusing duct having an area ratio of 1.9, length of 300 mm and turning angle of 22.5°/22.5°. The static pressure, total pressure, velocity and turbulence intensity were accounted. The improvement is observed for both, clockwise and anti-clockwise swirl, the improvement being higher for clockwise swirl. Flow uniformity at the exit is more uniform for clockwise swirl at the inlet.

Keywords: Curved diffusers, intake ducts, swirling flow, secondary flows, pressure recovery

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Paper Type	:	Research Paper
Title	:	Identification and Monitoring the Change of Land Use Pattern Using Remote Sensing and GIS: A Case Study of Dhaka City
Country	:	Bangladesh
Authors	:	Abdullah Al Mamun, Asif Mahmood, Mafizur Rahman
	:	10.9790/1684-0622028

Abstract: Dhaka is one of the fastest growing megacities of the world with a dense population over 15 million. Being the capital of a developing country like Bangladesh, it is experiencing multi-dimensional problems such as over urbanization, traffic congestion, water logging, solid waste disposal, black smoke from brick kilns and industrial emissions, sound pollution, pollution of water bodies by industrial discharge and the newly added calamity, building collapse. Dhaka is a sheer example of having poor legislative actions, inefficient management and lack of public awareness, which leads the urbanization to an unplanned and resource consuming development. This paper presents an integrated study of urbanization trends in Dhaka City, Bangladesh, by using Geographical Information Systems (GIS) and Remote Sensing (RS). This study explores the land use change pattern of Dhaka City Corporation over 1990-2010, through interactive supervised land cover classification using Landsat images by ArcGIS 10. The remotely detected land use/cover change from 1990 to 2010 shows that Dhaka is gradually changing as vegetative cover and open spaces have been transformed into building areas, low land and water bodies into reclaimed built up lands. These changes are mainly governed by unplanned urban expansion.

Keywords - ArcGIS 10.0, Dhaka City Corporation, GIS, Land Use Pattern, Remote Sensing.

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Paper Type	:	Research Paper
Title	:	Thermal Performance Evaluation of a Direct Absorption Flat Plate Solar Collector (DASC) using Al2O3-H2O Based Nanofluids
Country	:	India
Authors	:	Vivek Verma, Lal Kundan
	:	10.9790/1684-0622935

Abstract: Due to the growing demand of energy and lesser availability of fossil fuels there is a shift in our energy concern towards renewable energy sources. There is no doubt that from all the available sources, solar energy is the best option with its minimum environmental impact. Now a days different types of solar collectors are widely used to harvest solar energy. It has been found that performance of the solar collector depends upon the characteristics of the working fluid which is used to harvest solar energy in solar collector. In the present work the effect of Al2O3-H2O based nanofluids on the direct absorption type solar collector has been investigated experimentally. Nanofluids are the new class of the fluids with their improved properties over the host/conventional fluids. The volume fraction of Al2O3 nanoparticles used is 0.005% and 0.05%. Efficiency of the collector is calculated for different mass flow rates (60, 80, 100 ml/hr) of Al2O3-H2O based nanofluids. From the results obtained by performing experiments, it has been found that collector efficiency increases about to 3-4% when Al2O3-H2O nanofluids are used as compared to simple water. Comparison of the collector efficiency for different mass flow rate and different concentrations are done. ASHRAE [4] standards were followed while performing all the experiments.

Keywords: Nanofluids, ASHRAE, Volume fraction, Efficiency, Collectors etc.

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