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An Investigation of SI Engine Performance Characteristics Changes under Fuel Switch from Gasoline to Bioethanol
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Vahid (Supervisor) ; Shafii, Behshad (Supervisor)
Abstract
Alternative fuels are considered as a solution to increase energy security, reduce dependence on conventional fossil fuels (gasoline and diesel), and reduce greenhouse gas emissions. In this context, bioethanol has been very much considered in recent years. This fuel is combined with gasoline and used by cars. Flexible fuel vehicles are cars that can be used in various blend of gasoline and ethanol. Ethanol has a higher octane number than gasoline, and its mixture with gasoline increases the number of octane fuels. However, this fuel has a lower thermal energy than gasoline, which increases the fuel consumption of ethanol and gasoline relative to pure gasoline. The purpose of this study is...
Simulation and Control of Solid Oxide Fuel Cell
, M.Sc. Thesis Sharif University of Technology ; Pishvaie, Mahmoud Reza (Supervisor)
Abstract
The advent of maturing fuel cell technologies presents an opportunity to achieve significant improvements in energy conversion efficiencies at different scales and environmental conservation simultaneously. This work deals with modeling, simulation and control of planar solid oxide fuel cell with internal reformer. The presented model is based on conservation laws (mass, energy, and momentum), besides an electrochemical model with all sorts of voltage losses (ohmic losses, activation overpotentials, and concentration overpotentials). Methane steam reforming, water-gas shift reaction, and hydrogen oxidation are the main reactions in this modeling scheme. The obtained governing equations lead...
An analytical and experimental study of a hybrid rocket motor
, Article Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering ; Vol. 228, Issue. 13 , December , 2014 , pp. 2475-2486 ; ISSN: 09544100 ; Soltani, M. R ; Sharif University of Technology
Abstract
The hybrid rocket motor is a kind of chemical propulsion system that has been recently given serious attention by various industries and research centers. The relative simplicity, safety and low cost of this motor, in comparison with other chemical propulsion motors, are the most important reasons for such interest. Moreover, throttle-ability and thrust variability on demand are additional advantages of this type of motor. In this paper, the result of an internal ballistic simulation of hybrid rocket motor in a zero-dimensional form is presented. Further to validate the code, an experimental setup was designed and manufactured. The simulation results are compared with the experimental data...
Performance of a single chamber microbial fuel cell at different organic loads and pH values using purified terephthalic acid wastewater
, Article Journal of Environmental Health Science and Engineering ; Volume 13, Issue 1 , April , 2015 ; 2052336X (ISSN) ; Kariminia, H. R ; Sharif University of Technology
BioMed Central Ltd
2015
Abstract
Background: Purified terephthalic acid (PTA) wastewater from a petrochemical complex was utilized as a fuel in the anode of a microbial fuel cell (MFC). Effects of two important parameters including different dilutions of the PTA wastewater and pH on the performance of the MFC were investigated. Methods: The MFC used was a membrane-less single chamber consisted of a stainless steel mesh as anode electrode and a carbon cloth as cathode electrode. Both power density and current density were calculated based on the projected surface area of the cathode electrode. Power density curve method was used to specify maximum power density and internal resistance of the MFC. Results: Using 10-times,...
Numerical study to evaluate soot formation in a jp combustor equipped to different types of swirler
, Article AIAA Propulsion and Energy Forum and Exposition, 2019, 19 August 2019 through 22 August 2019 ; 2019 ; 9781624105906 (ISBN) ; Ghafourizadeh, M ; Schneider, G. E ; Sharif University of Technology
American Institute of Aeronautics and Astronautics Inc, AIAA
2019
Abstract
This paper is concentrated on soot formation in a JP combustor and it studies the emission in its exhaust gases when the combustor is equipped with different types of exhaust swirler. So, to approve the developed solver, it is required to predict one related flame structure accurately right at the first step. In this regard, we solve a well-documented benchmark test case with available data from experiment. These data are then compared with the current numerical results to evaluate the discrepancies. The comparison indicates that there is good agreement between them. Afterwards, we equip a similar combustor with different types of swirler, simulate the new designed combustor configurations,...
Numerical study to evaluate soot formation in a jp combustor equipped to different types of swirler
, Article AIAA Propulsion and Energy Forum and Exposition, 2019, 19 August 2019 through 22 August 2019 ; 2019 ; 9781624105906 (ISBN) ; Ghafourizadeh, M ; Schneider, G. E ; Sharif University of Technology
American Institute of Aeronautics and Astronautics Inc, AIAA
2019
Abstract
This paper is concentrated on soot formation in a JP combustor and it studies the emission in its exhaust gases when the combustor is equipped with different types of exhaust swirler. So, to approve the developed solver, it is required to predict one related flame structure accurately right at the first step. In this regard, we solve a well-documented benchmark test case with available data from experiment. These data are then compared with the current numerical results to evaluate the discrepancies. The comparison indicates that there is good agreement between them. Afterwards, we equip a similar combustor with different types of swirler, simulate the new designed combustor configurations,...
Model for optimizing energy efficiency through controlling speed and gear ratio
, Article Energy Efficiency ; Volume 1, Issue 1 , 2008 , Pages 65-76 ; 1570646X (ISSN) ; Farzaneh, H ; Sharif University of Technology
2008
Abstract
Specific fuel consumption of vehicles has been improved through technical changes in the last three decades. There has been little study of the impact of behavioral aspects on the specific fuel consumption of vehicles. Analytical tools developed recently have included options for quantifying the specific fuel consumption in certain predefined driving cycles. Empirical studies have shown that real driving cycles are different from predefined ones. It has also been observed that optimal coordination of both speed of vehicle and gear ratio are detrimental to the improved performance of a vehicle. Previous studies have only considered the vehicle speed as the explanatory parameter, and gear...
Energy and exergy analysis of internal reforming solid oxide fuel cell-gas turbine hybrid system
, Article International Journal of Hydrogen Energy ; Volume 32, Issue 17 , December , 2007 , Pages 4591-4599 ; 03603199 (ISSN) ; Sharif University of Technology
2007
Abstract
The aim of this work is to analyze methane-fed internal reforming solid oxide fuel cell-gas turbine (IRSOFC-GT) power generation system based on the first and second law of thermodynamics. Exergy analysis is used to indicate the thermodynamic losses in each unit and to assess the work potentials of the streams of matter and of heat interactions. The system consists of a prereformer, a SOFC stack, a combustor, a turbine, a fuel compressor and air compressor, recuperators and a heat recovery steam generator (HRSG). A parametric study is also performed to evaluate the effect of various parameters such as fuel flow rate, air flow rate, temperature and pressure on system performance. © 2007...
Modeling of gas turbine combustor using dynamic neural network
, Article 2006 ASME International Mechanical Engineering Congress and Exposition, IMECE2006, Chicago, IL, 5 November 2006 through 10 November 2006 ; 2006 ; 10716947 (ISSN); 0791837904 (ISBN); 9780791837900 (ISBN) ; Mozafari, A. A ; Sharif University of Technology
American Society of Mechanical Engineers (ASME)
2006
Abstract
This paper presents an Artificial Neural Network (ANN) - based modeling technique for prediction of outlet temperature, pressure and mass flow rate of gas turbine combustor. ANN technique has been developed and used to model temperature, pressure and mass flow rate as a nonlinear function of fuel flow rate to the combustion chamber. Results obtained by present modeling are compared with those obtained by experiment. A quantitative analysis of modeling technique has been carried out using different evaluation indices; namely, Mean-Square-Quantization-Error (MSQE) and actual percentage error. The results show the effectiveness and capability of the proposed modeling technique with reasonable...
Simulation and designing of methanol production plant based on the synthesis gas
, Article CHISA 2006 - 17th International Congress of Chemical and Process Engineering, Prague, 27 August 2006 through 31 August 2006 ; 2006 ; 8086059456 (ISBN); 9788086059457 (ISBN) ; Haddadi, A. M ; Kazemini, M ; Sharif University of Technology
2006
Abstract
Regarding the energy and environment crisis in the current century and future that threatens human communities, necessity of study and use of supplement fuels is felt more than before. Consumption of natural gas has been increasing rapidly making it one of the most important energy resources in the world. During the last decade the consumption of natural gas increased by almost 25%. By 2020 natural gas is predicted to increase its world energy share to as much as 50% from the present of 22%. The scale of its reserves and its environmental advantage favor its use, (the lower carbon emissions compared to oil and coal along with other reduced emissions of nitrogen oxides and particulates) for...
An experimental kinetic optimization of NDMA hydrogenation to UDMH and DMA on a Pd/C catalyst
, Article CHISA 2006 - 17th International Congress of Chemical and Process Engineering, Prague, 27 August 2006 through 31 August 2006 ; 2006 ; 8086059456 (ISBN); 9788086059457 (ISBN) ; Kazememi, M ; Bozorgmehri, R ; Sharif University of Technology
2006
Abstract
The Unsymmetrical dimethyl hydrazine (UDMH) apart from its use as a versatile rocket fuel, finds numerous industrial applications. Interest in UDMH for various applications in the missile and rocket industry has prompted the study of this member of hydrazine family to greater extent. It can be prepared in several ways but one of the most efficient ones which results in higher yields is the catalytic hydrogenation of Nitroso Dimethylamine (NDMA). In this work the kinetic of NDMA to UDMH hydrogenation on a 5% Pd/C in aqueous solution of NDMA was studied experimentally and optimum conditions of the reaction for maximum yield of UDMH in the presence of undesired dimethyl amine (DMA) product was...
Development of energy management system for A parallel hybrid electric vehicle using fuzzy logic
, Article 8th Biennial ASME Conference on Engineering Systems Design and Analysis, ESDA2006, Torino, 4 July 2006 through 7 July 2006 ; Volume 2006 , 2006 ; 0791837793 (ISBN); 9780791837795 (ISBN) ; Nabi, A ; Salmasi, F. R ; Amiri, M ; Sharif University of Technology
2006
Abstract
In this paper a fuzzy power controller for a parallel hybrid passenger car is developed in order to minimize its fuel consumption and optimize its components efficiencies. This is done by controlling the engine operating points in its optimal region and maintaining the SoC of batteries and electric motor operating point at the highest possible efficiency. Of course the designed control strategy must be able to obey the driver's commands and achieve the PNGV regulations. The controller implemented in this paper is a Mamdani fuzzy logic controller which takes the batteries SoC, electric motor's speed, ICE speed and the total demanded torque as its input variables and gives the ICE torque as...
Velocity regulation of a solid fuel ramjet using neural networks and adaptive sliding control
, Article 2005 ASME International Mechanical Engineering Congress and Exposition, IMECE 2005, Orlando, FL, 5 November 2005 through 11 November 2005 ; Volume 74 DSC, Issue 1 PART A , 2005 , Pages 239-248 ; 0791842169 (ISBN); 9780791842164 (ISBN) ; Alemohammad, H ; Sharif University of Technology
2005
Abstract
This paper presents velocity control of a Solid Fuel Ramjet (SFRJ) in variable flight conditions. Since SFRJ is classified as an air breathing propulsion system its performance depends on the air flow over the solid fuel. Dynamic modeling of internal ballistics of SFRJ is developed using gas dynamic relations. This results in a set of nonlinear differential equations. The nonlinearity of equations comes from the fact that gas dynamic relations are generally nonlinear and since the value of some ballistic properties of SFRJ are inaccurate, uncertainties are available in dynamic equations. Then, an adaptive sliding controller is designed for velocity regulation of SFRJ. In order to design the...
Computational analysis of injection-velocity effects on dynamic parameters of unconfined fuel-vapor clouds
, Article Combustion, Explosion and Shock Waves ; Volume 41, Issue 5 , 2005 , Pages 510-520 ; 00105082 (ISSN) ; Mazaheri, K ; Hosseinalipour, M ; Sharif University of Technology
2005
Abstract
A computational investigation is performed to study the effects of injection velocity on the main dynamic parameters of the fuel cloud released into the open atmosphere. The volume, shape, and growth rate of the cloud, turbulence intensity, as well as the distribution of fuel concentration, temperature gradient, and self-ignition induction time are the most important parameters determining the mode of combustion that propagates through the cloud. A modified KIVA-based program is employed to fulfill the calculations. Systems of equations are solved by a finite-volume method. The k-ε model and discrete droplet model are applied for modeling gas-phase turbulence and liquid spray, respectively....
Optimization of a combined heat and power PEFC by exergy analysis
, Article Journal of Power Sources ; Volume 143, Issue 1-2 , 2005 , Pages 179-184 ; 03787753 (ISSN) ; Ehyaei, M. A ; Abbasi, A ; Sharif University of Technology
2005
Abstract
In this paper, design and exergy method optimization of a 5 kW power output polymer electrolyte fuel cell (PEFC) fuel cell with cogeneration application has been investigated. It is assumed that cooling water is passed through the fuel cell cooling channel, warmed up and supplied for space heating applications. The performance of the proposed system has been optimized by the second law based on exergy analysis. Results show that for maximum system efficiency and minimum entropy generation, fuel cell temperature and voltage should be as high as possible in the range of application. Also, the fuel cell pressure and stoichiometric air:fuel ratio should be as low as possible in the range of...
An Investigation About Using Engineering Polymers, Polycarbonate and Polysulfone, as Membrane in Fuel Cells
, M.Sc. Thesis Sharif University of Technology ; Ramazani Saadatabadi, Ahmad (Supervisor) ; Musavi, Abbas (Supervisor)
Abstract
In this work, sulfonated polycarbonate (SPC ) membranes with different acid contents have been prepared by conducting sulfonation reaction at room temperature using Chlorosulfonic acid (CSA) as sulfonating agent at different concentration of acid in reacting solution. The SPC membranes were obtained by casting from 10% solution of SPC in chloroform at room temperature. The prepared membranes were characterized using Ion exchange capacity (IEC), and degree of sulfonation (DS), Fourier Transform Infrared (FTIR), NMR spectra, Thermal Gravimetric Analysis (TGA) and Water uptake. The obtained results showed that with increaseing in Chlorosulfonic acid content in sulfonation reaction IEC and DS of...
Feasibility And Study(CNG Cylinder Production Plant)
, M.Sc. Thesis Sharif University of Technology ; Haji, Alireza (Supervisor)
Abstract
Nowadays best using of fossil fuels sources of the country (and) importance of comparison against lack of capacity in petrol production make determined the programmers and the directors to foresee and design expanded programs of the goals, to use natural gas for car fuels. To reach fulfillment of these programs, the confirmed needs of the natural gas cylinders are improved and make it essential to invest on producing compressive natural gas cylinders. In this way economical and technical change researches has been done in order to construct on department to produce 200,000 compressive natural gas cylinders in a year during two sets.(shifts) According to the results of technical researches...
Analysis of Nano Particles Application in Perfprmance of Polysulfone Fuel Cell Membrane
, M.Sc. Thesis Sharif University of Technology ; Ramezani saadat abadi, Ahmad (Supervisor) ; Mousavi, Abbass (Supervisor)
Abstract
Today, energy crises and the environmental pollution have become serious problems for the human being. To address these problems, extensive efforts have been made to replace fossil fuels with other clean energy resources such as fuel cells. In the meantime, polymer electrolyte fuel cells are very important as they are now commonly used in the field of transportation, and their importance become even more obvious as we consider the fact that the by-products from electricity production by such cells are simply water and heat. This research studies the efficiency of the polymer called “polysulfone” as an electrolyte fuel cell, which has the above named mechanical thermal and chemical...
Investigate and Analysis of Experimental Integrated Energy System Based on Microbial Fuel Cell to Produce Electrical Energy, Wastewater Treatment, Carbon Dioxide Capturing and Biomass Production
, M.Sc. Thesis Sharif University of Technology ; Roshandel, Ramin (Supervisor) ; Yaghmaei, Soheila (Supervisor)
Abstract
In this study, simultaneous production of bioelectricity and algal biomass, wastewater treatment and carbon dioxide capturing in an Algal-Cathode Photosynthetic Microbial Fuel Cell has been evaluated. The performance of the system under different light intensity (3500, 5000, 7000 and 10000 lux) and also different light:dark regime (24:00, 12:12 and 8:16 hour) has been studied. The results show that, light intensity has direct effects on performance of Photosynthetic Microbial Fuel Cell (PMFC) with changing dissolved oxygen in biological cathode. So, the PMFC can reach power density of 125.96 mW/m3 with optimized light intensity of 5000 lux and simultaneously columbic efficiency and COD...
The Use of Non-platinum Electro-catalyst for Low Temperature Fuel Cells
, M.Sc. Thesis Sharif University of Technology ; Samiee, Leila (Supervisor) ; Seifkordi, Ali Akbar (Co-Advisor)
Abstract
In the recent decades, Polymer Electrolyte Membrane Fuel Cells (PEFC) have been known as an appropriate type of fuel cells, due to being electrochemical converter and clean energy generator with high power density and having low operation temperature and launch time. Palatine is one of the major materials that are used in electro-catalysts of fuel cell. Due to shortage of palatine resources and its high price, fuel cell production is not economical. To achieve economic conditions for production of fuel cell, two major methods are proposed:
1) Reduction of the employed amount of palatine in electro-catalyst
2) Full replacement of palatine with cheap materials
In the current...
1) Reduction of the employed amount of palatine in electro-catalyst
2) Full replacement of palatine with cheap materials
In the current...