The Future of Conventional Aircraft Ground Propulsion Systems in Relation to Fuel Consumption and CO2 Emission
IJTEE, volume-13 , Issue 2 (2016), PP 91 - 100
Published: 28 Jan 2017
by Iniobong Edem, Owunna Ikechukwua , Ikpe Aniekan E, Ememobong E. Ikpe from Department of Mechanical Engineering, Coventry University, Priory Street, CV15FB, West Midlands UK Department of Instrumentation and Control, Exxon Mobil Producing Nigeria, Eket, Akwa Ibom State, Nigeria
Abstract: Aircraft spends a minimum of 20 minutes using its main engine to taxi from the airport terminal gate to the runway, where the aircraft takes-off and similarly to the terminal gate after landing. During taxi operation, aircraft burns a lot of fuel, generates large quantity of emissions and the engine in the process of taxiing is exposed to damage due to Foreign Object Damage (FOD). This results in huge operational and maintenance cost as well as carbon emission tax which are all at the expense of the airline. EGTS is a recent technology designed to prevent aircraft from using its main engine for taxi operation and this in turn reduces the rate of fuel consumption, slashes carbon emissions and minimises operational and maintenance cost. This paper examines the viability of using EGTS in single engines for taxi operation rather than the aircraft engine. Block fuel savings was calculated for two engine, single engine and hybrid aircraft and it was observed that two engine aircraft using EGTS saved 110kg block fuel, single engine saved 74kg and for hybrid engine the block fuel savings was 50kg. Block fuel savings was calculated for aircraft such as airbus A320, airbus A380, Cessna 172 and A600ST and it was observed that EGTS is more compatible with airbus A320 but was not recommended for A600ST and A380 due to extra weight implication and for Cessna 172, EGTS was not necessary because the aircraft weight is low and consumes less fuel already. It was observed that the higher the aircraft weight including the extra weight of EGTS, the higher the fuel consumption emission as well as the torque required to overcome drag force when the aircraft operates in air. CO2 emission was also calculated for aircraft with EGTS and aircraft without installation, the result for aircraft with EGTS showed 797.56kg reduction of CO2 emission when compared to aircraft without EGTS. Comparably, EGTS was proven to be viable in terms of fuel savings, CO2 emissions, operational and maintenance cost than its contemporary Ground Propulsion Systems (GPS) for single aircraft engines and therefore, was recommended for aircraft in airbus A320 category to help minimise global warming which results from CO2 emission during taxing operations. Key read more... read less...
Keywords: Aircraft, CO2 Emission, Fuel Consumption, Weight, Ground Propulsion, Cost Savings
IJTEE, volume-13 , Issue 2 (2016), PP 81 - 89
Published: 16 Jan 2017
by Bruce Spencer, Feras Al-Obeidat, Omar Alfandib, from University of New Brunswick, Fredericton, Canada Zayed Universty, Abu Dhabi, UAE University of Göttingen, Göttingen, Germany
Abstract: We forecast internal temperature in two homes, using variants of regression with data from the readings of multiple sensors. We use 48 separate models, where each forecasts mean temperatures that will occur in one future 15-minute interval, to compose a forecast for the next 12 hours. The sensors report internal and external atmospheric and environmental conditions such as temperature, pressure, sunlight, rain and wind, as well as evidence of human activity, including CO2 saturation, motion sensors and electrical load from areas within the house and large appliances. The models use both current and historical sensor values, each of which increases the number of predictors in the linear regression model. We use model simplification techniques including forward stepwise regression, principal component regression, and partial least squares regression. In both houses the forecast accuracy is stable; the mean absolute error over 12 hours is less than 1, while the root mean squared error is less than 1.3. Our accuracy compares favorably to previous work. Our work indicates long sensor histories for forecasts in the next 12 hours do not significantly improve accuracy. read more... read less...
Keywords: Smart Home, Linear Regression, Temperature Forecasting
IJTEE, volume-13 , Issue 2 (2016), PP 75 - 80
Published: 04 Jan 2017
by M. M. Rahman, H. Bhowmik, S. Talukdar from Department of Mechanical Engineering, University of Saskatchewan, Canada Department of Mechanical Engineering, DUET, Gazipur, Bangladesh
Abstract: Three dimensional numerical models were developed to make prediction free convection heat transfer at steady state condition from radial flow heat sink. The air was considered as the medium of heat transfer. In radial flow heat sink, heat conducts through base in radial pattern and is uniformly transported to the fins. The Tagucy method was used to investigate the effect of several design parameters such as fin length, fin height, number of fins and heat sink base radius on heat transfer. There are five factors and four levels on each factor were chosen. Sixteen types of model were analyzed to obtain total heat transfer for each model. The result was used to estimate the optimum designed values of the parameters affecting the heat sink efficiency. The reproducibility of the optimum design value was verified. The average rate of heat transfer of optimum model was increased by more than 50 % than the reference model. Finally, the heat transfer data of radial flow heat sink were correlated of several outer radius by an equation. read more... read less...
Keywords: Natural convection, Laminar flow, Radial flow, Heat transfer, Optimization
Evaluation of Environmental Impacts Resulting from Electric Power Generation and Steel Manufacturing using Coal as Fuel Source
IJTEE, volume-13 , Issue 2 (2016), PP 143 - 153
Published: 29 Jan 2017
by Aniekan E. Ikpe, Owunna Ikechukwu, Ememobong Ikpe from Department of Mechanical Engineering, Coventry University, Priory Street, CV15FB, West Midlands UK Department of Instrumentation and Control, Exxon Mobil Producing Nigeria, Eket, Akwa Ibom State, Nigeria
Abstract: Our environment is extremely important to Intergovernmental Panel on Climate Change (1PCC) and other environmental protection agencies because it is a place where flora and fauna as well as the entire human population of the world exist. This report evaluates the environmental impacts resulting from the use of coal as a source of fuel for electricity power generation and coal as a fuel source to generate electricity for steel production process. GABI models were developed for each of the processes and used for the assessment and analysis to ensure compliance with ISO 14044 standards. After identifying the numerous forms of emission obtained from GABI software, the results were compared to determine the environmental impact and severity of each process. The result for Global Warming Potential (GWP) using coal as a fuel source for steel production accounted for 129.7029 Kg of CO2 equivalence compared to 0.447267Kg of CO2 equivalence result obtained as the GWP for using coal as fuel source for electric power generation. Similarly, the result obtained for acidification when coal is used as a fuel source for steel production recorded 0.360921Kg of SO4 equivalence compared to 1.4026Kg of SO4 equivalence obtained as acidification value for using coal as fuel source for electric power generation. Furthermore, the result obtained for Eutrophication when coal is used as a source of fuel for steel production accounted for -1389.273e-4Kg of phosphate equivalence compared to 2.2417Kg of phosphate equivalence obtained as the Eutrophication value for using coal as a source of fuel for electric power generation. From the aforementioned results, Eutrophication potential and Acidification potential would have lower environmental impacts for both processes whereas, the GWP for electric power generation was quite minimal while GWP for steel production using coal as a fuel source would have relatively high impact on the environment. For this reasons, it was concluded that electric power generation using coal as a source of fuel has less environmental impact whereas, steel production using coal as a source of fuel may not be environmentally friendly due to the high GWP obtained in this report. read more... read less...
Keywords: Coal, Life Cycle Analysis, Environmental Impact, Power Generation, Steel Manufacturing
Revamped Cooling of a Rectangular Shaped Chip Inserting a Highly Conductive Solid: Coupled vs. Uncoupled Conceptions
IJTEE, volume-13 , Issue 2 (2016), PP 135 - 141
Published: 28 Jan 2017
by M. R. Hajmohamdami, A. Campob from Department of Mechanical Engineering, Amirkabir University of Technology, Tehran, 158754413, Iran Department of Mechanical Engineering, The University of Texas at San Antonio, San Antonio, TX, 78249, USA
Abstract: The performance of highly conductive inserts embedded into a heated chip has been investigated in recent years. The role of the insert was to gather the heat current within the chip and remove it to a low temperature heat sink. The central goal of this study is to invoke several reconsiderations, which results in the plausible reduction of the peak temperature in a heated rectangular chip in comparison with the lowest peak temperature achieved in previous works. It is proved that for the configuration under study with its bottom surface receiving a constant uniform heat flux, the branching patterns of the insert must be avoided, instead the appropriate revisions in the architecture (width, location and cross section area) of the insert are accounted for the simple patterns. An uncoupled analytical solution for predicting the peak temperatures in the rectangular chip containing the cooling insert is also addressed. It is also proved that under the same volume fraction and thermal conductivity of the insert, the peak temperature can be reduced to 2.9 °C, which is 94% below the lowest temperature reported in the archival literature, which was around 50.5 °C. read more... read less...
Keywords: electronics cooling, rectangular chip, highly conductive insert, minimized peak temperature
IJTEE, volume-13 , Issue 2 (2016), PP 129 - 133
Published: 28 Jan 2017
by E.K. Orhorhoro, O.W. Orhorhoro, A.E. Ikpe from Cemek Machinery Company, Technology Incubation Centre, Federal Ministry of Science & Technology, Nigeria Electrical/Electronic Engineering Department, Delta State Polytechnic Oghara, Nigeria Department of Mechanical Engineering, University of Benin, Benin City, Nigeria
Abstract: In this paper, a study was carried out on solar energy potential in Sapele, Nigeria. Five photovoltaic solar panel (cell) connected in series where used to generate data on maximum and minimum temperature readings, voltage and current readings for a period of 50 days. The result obtained shown that a mean average temperature readings of 30.01 °C, mean average voltage readings of 14.23 V and mean average current reading of 4.206 A were obtained. The global solar radiation and extraterrestrial solar radiation were calculated as 11.09 kwh/m2 /day and 5.31kwh/m2 /day respectively. Considering the average power deposited (0.060 kW and 0.180 kWh) read more... read less...
Keywords: Solar energy potential, temperature, power deposited, global solar radiation, Sapele, Nigeria
Engine Performance and Emission Characteristics of a Direct Injection Diesel Engine Fuelled with 1- Hexanol as a Fuel Additive in Mahua Seed Oil Biodiesel Blends
IJTEE, volume-13 , Issue 2 (2016), PP 121 - 127
Published: 28 Jan 2017
by V. Dhana Raju, K. Kirankumar, P.S. Kishore from Mechanical Engineering Department, LBRCE, Mylavaram, India Mechanical Engineering Department, Amrita sai Institute of Science &Technology, Paritala, India Mechanical Engineering Department, Andhra University, Vizag, India
Abstract: The increasing industrialization and motorization of the world has led to a steep rise for the demand of petroleum products. Petroleum based fuels are obtained from limited reserves. In the wake of this situation, there is an urgent need to promote use of alternative fuel which must be technically feasible, economically competitive, environmentally acceptable and readily available. In the present study, Mahua seed oil methyl esters (MSOME) were prepared through transesterification and evaluation of important physico-chemical properties was carried and the properties were found within acceptable limits. A compression ignition engine was fuelled with three blends of MSOME with diesel (10, 20 and 30% on volume basis) and various performance and emission characteristics were evaluated and results compared with baseline data of diesel. The results suggest the BTE was higher for MSOME blends and BSFC, HC and smoke opacity were lower as compared to diesel fuel. This may be attributed to improved combustion for MSOME are oxygenated fuels and have higher cetane number. The values of NOx were found almost nearer for all blends as compared to diesel. Addition of 1-hexanol (Ignition improver) 0.5%, 1% volume ratios to the optimum blend (MSOME30) for evaluating the engine performance and emissions parameters and the main purpose of ignition improver is to improve combustion process and reduction in engine emissions. Finally results shows that performance and emissions have been to justify the potentiality of the mahua seed oil methyl esters as alternative fuel for compression ignition engines without any modifications. read more... read less...
Keywords: Mahua seed oil, Transesterification, Bio-diesel, Methanol, NOx
IJTEE, volume-13 , Issue 2 (2016), PP 113 - 120
Published: 28 Jan 2017
by B.G. Prashantha, M.S. Govinde Gowda, S. Seetharamu, G.S.V.L. Narasimham from Department of Industrial Engineering & Management, JSS Academy of Technical Education, Dr. Vishnuvardhana Road, Bangalore-560 060, India Department of Mechanical Engineering, Nagarjuna College of Engineering and Technology, Bengaluru-562 164, India Central Power Research Institute, Bangalore-560 080, India Department of Mechanical Engineering, Indian Institute of Science, Bangalore-560 012, India
Abstract: In this paper, thermoacoustic refrigerator design strategy with parameters normalization and literature review covering the recent development in the modification of the resonator shape and size is discussed. The design of a 10 W cooling power thermoacoustic refrigerator using air as working substance and the effect of operating frequency on viscous and thermal penetration depths, and on stack sheet thickness and spacing are discussed. The promising 10 W cooling power TDH (Taper and Divergent section with Hemispherical end) resonator design operating with air and helium gases as working substances is analyzed using DeltaEC software. The analysis results show that the TDH resonator design using helium as working substance operates at lower drive ratio (14%) compared to air (25%). In comparison, DeltaEC predicts a decent low temperature of -35.4 o C at cold heat exchanger with a COP of 0.5294 when operated using helium gas, and for air is -9 oC and 0.8113 respectively, and the results are discussed. read more... read less...
Keywords: Thermoacoustic, TDH design, Drive ratio, DeltaEC
Fabrication and Performance Evaluation of Savonious Vertical Axis Wind Turbine for Uncertain Speed Regions
IJTEE, volume-13 , Issue 2 (2016), PP 107 - 111
Published: 28 Jan 2017
by S. Naga Kishore, T. Venkateswara Rao, M.L.S. Deva Kumar from Department of Mechanical Engineering, RSR Engineering College, Kadanuthala, AP, India Department of Mechanical Engineering, KL University, Vaddeswaram, AP, India Department of Mechanical Engineering, JNTUCEA, Anantapur, AP, India
Abstract: The consumption of electricity in urban as well as rural is increasing every day and became an essential commodity for household and industrial purposes. Unfortunately the availability of electrical energy in India is not sufficient to the required demand and it is essential to discover and generate energy from non-conventional sources with cheap cost. On the same time it is necessary to reduce the consumption of conventional sources and to save fuel. Among all the renewable resources, wind is one of the best resources available all the time at free of cost. Especially vertical axis wind turbines (VAWT) are self-starting, omni directional. They require no yaw mechanism to continuously orient towards the wind direction and provide a more reliable energy conversion technology, as compared to horizontal axis wind turbine. Particularly savonius vertical axis wind turbines (SVAWT) are suitable and practically possible at low or uncertain wind speed regimes. They can be fitted on rooftops and also suitable for the urban areas where electricity is not available properly. This project deals with the fabrication and performance evaluation of savonius vertical axis wind turbine using two blade rotor. The amount of power developed by the wind turbine is calculated under theoretical and practical conditions and aerodynamics coefficients are also estimated. And various design parameters of savonious rotor are identified and determined. read more... read less...
Keywords: Savonious, Vertical Axis Wind turbine, Velocity, Power, Rotor.
IJTEE, volume-13 , Issue 2 (2016), PP 101 - 105
Published: 28 Jan 2017
by M. Mujahid Rafique from Department of Mechanical Engineering, King Fahd University of Petroleum and Minerals, Dhahran, Saudi Arabia
Abstract: The liquid desiccant cooling system is found to be a good alternative of conventional air conditioning system for better control of both latent and sensible loads. The major component of a liquid desiccant cooling system is desiccant dehumidifier which controls the latent cooling load. In this paper a mathematical model for rotary type liquid desiccant dehumidifier commonly known as desiccant wheel has been presented. The desiccant wheel has a cylindrical shape with a number of identical narrow circular slots distributed uniformly over the rotor cross section. The slots are filled with a porous medium carrying the solution of liquid desiccant, to make the absorbing surface. The absorption and regeneration performance of the desiccant dehumidifier is discussed in this paper for different operating conditions. The wheel performance curves which help to determine the air outlet conditions and coefficient of performance (COP) of the system are drawn for a wide range of wheel thickness (0.06-0.6m), air mass flux (1-8 kg/m2 .s), and regeneration temperature (60- 85o C). A reduction of about 30% in outlet humidity ratio is observed with an increase in the wheel thickness from 0.06 to 0.2m. The computed results show that better supply air conditions can be obtained to provide human thermal comfort in the hot and humid climate with effectiveness of the system largely dependent on air flow rate, wheel thickness and humidity ratio of process air. read more... read less...
Keywords: Liquid desiccant wheel, heat and mass transfer coefficients, air conditioning, mathematical model.
IJTEE, volume-13 , Issue 1 (2016), PP 7 - 12
Published: 27 Jul 2016
by N. Adam, A. Shanableh from Department of Civil and Environmental Engineering University of Sharjah, Sharjah, United Arab Emirates Research Institute of Sciences and Engineering, University of Sharjah, PO Box 2727, Sharjah, United Arab Emirates
Abstract: The purpose of this study was to assess the potential of combining the production of three types of biofuels (i.e., biodiesel, bioethanol, and biogas) from Nannochloropsis sp. microalgae. Cellulase enzyme, produced from Trichoderma viride fungi was used to convert algal hydrocarbons into sugars for bioethanol production and to improve lipids extraction for biodiesel production. The procedure for producing the three biofuels consisted of initially mixing predetermined quantities of cellulose with the algae to hydrolyze the complex hydrocarbons and produce sugars, followed by oil extraction from the hydrolyzed algae, and finally producing biogas through co-digesting the hydrolyzed and oil-extracted algae residual with wastewater treatment sludge. Without enzyme, the total sugar yield following hydrolysis for 6 hours with distilled water at 37°C and pH 5 reached 38 mg/g algae. Using the enzyme, total sugar production increased in the range of 42 mg/g algae to 74 mg/g algae with increasing enzyme use. Similarly, the reducing sugar production increased from 36 mg/g algae without enzyme to 60 mg/g algae with increasing enzyme dose. Following hydrolysis, the lipids yield reached 59% of the extracted algae weight, which represents almost all of the lipids in the algae. The residual algae mixed with sludge generated significant amounts of biogas in excess of the quantities generated by sludge alone. The results demonstrated the technical feasibility of producing three biofuels from algae; however the economic aspects of the process require significant further careful consideration. read more... read less...
Keywords: Biofuels, Biogas, Biodiesel, Ethanol, Enzymatic Hydrolysis, Sugars, Oil, Renewable Energy, Microalgae.
IJTEE, volume-13 , Issue 1 (2016), PP 67 - 74
Published: 24 Dec 2016
by Hassan S. Ghalib, Muneer A. Ismael from Mechanical Engineering Department, Engineering College, University of Basrah, Basrah, Iraq
Abstract: This paper investigates the double diffusive natural convection in a partially porous layered enclosed cavity with a thermally conductive square body. The horizontal walls are thermally insulated, the left wall adds heat isothermally into the porous layer, while the right wall is cooled isothermally. The center of the square conductive body is positioned in the center of the cavity in such a way it lays on the porous-fluid interface. The governing equations have been solved using up-wind scheme finite difference method. The Parndtl number, thermal conductivity ratio of the body to fluid, Darcy number, aspect ratio of the square body to the cavity sides have fixed at 6.26, 1, 10-3, 0.5, respectively. The study has been governed by three parameters namely, Lewis number (Le = 1–50), buoyancy ratio (-10 – 10), and Rayleigh number (103 - 106 ). The results have showed that the mass diffusivity ratio, which takes into account non-unity tortuosity ratio (Deff/D = 0.53) has a significant effect on the mass transfer than the unity value. It is found also that Sherwood number is minimal when the buoyancy ratio equals to -0.5, otherwise, it increases with increasing the absolute value of the buoyancy ratio. read more... read less...
Keywords: Double-diffusive, partitioned cavity, porous medium, inner body, finite difference