Search for: gasoline
Total 81 records
An assessment of gasoline motorcycle emissions performance and understanding their contribution to Tehran air pollution, Article Transportation Research Part D: Transport and Environment ; Volume 47 , 2016 , Pages 1-12 ; 13619209 (ISSN) ; Hosseini, V ; Sharif University of Technology
Motorcycles are the third most common means of transportation in the megacity of Tehran. Hence, measurements of emission factors are essential for Tehran motorcycle fleets. In this study, 60 carburetor motorcycles of various mileages and engine displacement volumes were tested in a chassis dynamometer laboratory according to cold start Euro-3 emissions certification test procedures. For almost all of the tested samples, the average carbon monoxide (CO) emission factors were about seven times higher than the limits for Euro-3 certification. No motorcycle fell within the Euro-3 certification limit on CO emissions. 125 cc engine displacement volume motorcycles, which are dominant in Tehran,...
Control oriented modeling of a radial turbine for a turbocharged gasoline engine, Article Proceedings of the American Control Conference ; Article number 6580648 , 2013 , Pages 5207-5212 ; ISSN: 07431619 ; ISBN: 9781479901777 ; Shahbakhti, M ; Alasty, A ; Vossoughi, G. R ; Sharif University of Technology
This paper presents a control oriented model for predicting turbine major variables in a turbocharged spark ignition engine. The turbine is simulated as a two-nozzle chamber where the pressure ratio over the two nozzles is not the same. A convex nonlinear estimation algorithm is formulated to determine the relation between these pressure ratios. The new model is experimentally validated with transient and steady state data collected from a 1.7 liter gasoline engine. The results show the new model can predict the turbine mass flow with an average error of 1.4%. In addition, the application of the turbine model is illustrated for the design of a nonlinear observer to estimate the turbocharger...
Solid acid catalytic alkylation: A means for gasoline-aromatics reduction, Article Proceedings of the 17th World Petroleum Congress, Rio de Janeiro, 1 September 2002 through 5 September 2002 ; Volume 3 , 2002 , Pages 405-416 ; Kazemeini, M ; Khorasheh, F ; Sahebdelfar, S ; Sharif University of Technology
Reduction of aromatics implies that the gasoline pool would suffer both quantitatively and qualitatively. Alkylates (highly branched paraffinic hydrocarbons) are ideal substitutes because of their high octane numbers, and environmental friendly characters. Alkylates have played significant roles in US gasoline pool, while in Europe alkylates have a lesser important role. The phase out of lead and the increased capacity of FCC units for making more gasoline from heavier petroleum cuts have enhanced the validity of alkylation processes in petroleum refineries. Based on the data obtained in the laboratory using a new developed catalyst, it is predicted to behave as a successful catalyst for C4...
Price elasticity of gasoline smuggling: a semi-structural estimation approach, Article Energy Economics ; Volume 71 , 2018 , Pages 171-185 ; 01409883 (ISSN) ; Rafizadeh, N ; Rahmati, M. H ; Sharif University of Technology
Elsevier B.V 2018
We estimate the price elasticity of the demand for gasoline smuggling in Iran. For this purpose, we employ a detailed panel of monthly gasoline consumption data from 160 distribution hubs during the period 2005–2014. We apply two different approaches which are diff-in-diff and panel data estimations. The results suggest that the foreign-to-home gasoline price ratios have a significant impact on the time-varying elasticity of demand. This finding supports the hypothesis that an increase in domestic gasoline prices will significantly reduce the demand for smuggling. In addition, as the distance of a region from its closest higher-price neighboring country diminishes, the price elasticity of...
Estimation of the Price Elasticity of Gasoline Smuggling Demand in Iran, M.Sc. Thesis Sharif University of Technology ; Rahmati, Mohammad Hossein
This study investigates the price elasticity of gasoline smuggling demand in Iran. For this purpose, a panel data of monthly gasoline consumption has been used that contains data for 160 regions of distribution for Iran's Oil Production Company between 2005 and 2014. The results of estimating the monthly elasticity of gasoline smuggling demand in each region show a significant impact of the gasoline price differential between Iran and its neighboring countries, as well as the distance of each region with the neighboring countries on the demand. The results of this study show that whenever gasoline prices increase inside the country, the inclination to smuggling has been decreased due to a...
Failure analysis of a cracked gasoline engine cylinder head, Article Journal of Failure Analysis and Prevention ; Volume 12, Issue 3 , 2012 , Pages 286-294 ; 15477029 (ISSN) ; Mafi, A ; Roozban, M ; Moghaddam, F ; Sharif University of Technology
This article presents a failure analysis on a gasoline engine cylinder head made of aluminum alloy, which has been used in passenger cars. During an endurance test, a crack initiated from the interior wall of a hole in the center of the cylinder head and then propagated through the thickness of the cylinder head. The metallurgical examinations are conducted in the crack origin zone. The results show that there are many casting pores due to poor quality of casting in the failed cylinder head which has certainly played a crucial role in initiating the crack. Finite element analysis of the cylinder head is performed to identify the stress components. Modeling of a bolt for the hole shows that...
Synthesis and adsorption performance of a modified micro-mesoporous MIL-101(Cr) for VOCs removal at ambient conditions, Article Chemical Engineering Journal ; Volume 341 , 1 June , 2018 , Pages 164-174 ; 13858947 (ISSN) ; Sheikh Alivand, M ; Rashidi, A ; Samimi, A ; Mohebbi Kalhori, D ; Sharif University of Technology
Elsevier B.V 2018
In this study, dynamic adsorption behavior of different gaseous volatile organic compounds (VOCs) on a new modified M-MIL-101(Cr) was investigated with a great emphasis on gasoline adsorption. The M-MIL-101(Cr) was synthesized, along with comprehensive purification procedures, using a new linker to cluster molar ratio (2:1 instead of 1:1) and different modulators (i.e. HF and HNO3). All prepared adsorbents were characterized by XRD, FTIR, FE-SEM and N2 adsorption-desorption at 77 K. The results showed that surface area and pore volume of the M-MIL-101@Free (i.e. modified MIL-101(Cr) with using any modulator) which were 4293 m2/g and 2.43 cm3/g, greatly elevated up to 37.2% and 71.6% against...
Numerical Modeling of Ethanol & Gasoline Direct Injection Spary in an Combustion Chamber, M.Sc. Thesis Sharif University of Technology ; Saidi, Mohammad Hassan ; Mozafari, Ali Asghar
First studies in internal combustion engines have focused on increasing engine power and efficiency, reducing engine volume and improving fuel quality. However, nowadays most studies are concentrated on decreasing exhaust emissions and usage of regenerative fuels while maintaining engine size, efficiency and power. Surveying fuel type in direct injection engines, requires investigation of microscopic and macroscopic spray characteristics including spray tip penetration, spray cone angle, spray area and sauter mean diameter, since these parameters determine air-fuel mixture quality. In this study, spray of ethanol as a regenerative fuel that reduces emissions such as NOx and CO is...
Computer simulation of turbocharged aftercooled gasoline engine, 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) ; Hajilouy Benisi, A ; Mozafari, A. A ; Sharif University of Technology
American Society of Mechanical Engineers 2006
Turbocharging of gasoline engines has been improved less than diesel engines due to some difficulties, especially knock phenomena. They require wider air flow range and faster response too. A computer code is developed to simulate turbocharged gasoline engine behavior. A three zone combustion model is employed. Different performance curves at speed and equivalence ratio ranges are prepared. By this code naturally aspirated and turbocharged behavior are compared. A turbocharged aftercooled engine has been studied in various cases to complete the investigation. Some aftercooler effects are described experimentally. Modeling and experimental results are compared providing valuable achievements....
Feasibility Study Of A Gas To Liquid Plant, M.Sc. Thesis Sharif University of Technology ; Hooshmand, Mahmoud
The methodology proposed by UNIDO , to investigate feasibility study of industrial project, is a useful tool in pre-investment decision making. In this work feasibility of investing on "Gas To Liquid" GTL Plant of Asalouye is investigated. Having gathered required information, including gas field potential, required technology and machineries, cost of investments , required manpower to run the UNIDO methodology is used to investigate the investment, the result of the work shows that the project is feasible and it would have internal rate of return of 24% ( by sale cost= 81 $ per barrel of GTL product)
Large eddy simulation of GDI single-hole and multi-hole injector sprays with comparison of numerical break-up models and coefficients, Article Journal of Applied Fluid Mechanics ; Volume 9, Issue 2 , 2016 , Pages 1013-1022 ; 17353572 (ISSN) ; Hosseini, V ; Afshin, H ; Allocca, L ; Baloo, M ; Sharif University of Technology
Isfahan University of Technology 2016
In the present study the fuel spray of a gasoline direct injected engine with multi-hole injector is simulated. Simulation inputs data, injection flow rate and spray cone angle are obtained from previous experimental studies. Log-normal distribution with different standard deviation is used for initial droplet size as the primary break-up model in order to reach the agreement between experimental and calculated spray tip penetration. As the first step, only one plume of spray injected into a quiescent air environment is simulated and validated by varying break-up model and standard deviation. Then, with coefficient obtained from the single jet simulation all six spray jets are simulated...
Fault effect analysis of the exhaust manifold leakage for a turbocharged spark ignition engine, Article Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering ; Vol. 228, issue. 8 , 2014 , pp. 970-984 ; ISSN: 09544070 ; Vossoughi, G ; Alasty, A ; Sharif University of Technology
Fault monitoring in internal-combustion engines is crucial for keeping the vehicle performance within the acceptable standards of emission levels and drivers' demands. This paper analyses how a vehicle's performance and engine variables are affected by a leakage fault in the exhaust manifold. The threshold leakage that causes the vehicle to exceed the emission standards is determined for a class M1 vehicle tested on a chassis dynamometer over the New European Driving Cycle. It is shown that, when a leakage of 6 mm diameter on the exhaust manifold is introduced, the vehicle emissions exceed those specified in the European 2013 on-board diagnostics standard. In addition, the effects of the...
Fuel consumption information: An alternative for congestion pricing?, Article Road and Transport Research ; Vol. 23, issue. 3 , Sep , 2014 , p. 52-64 ; 10375783 ; Zarei, H ; Sharif University of Technology
People's poor perception of the amount they spend on fuel is considered to be an important reason for the low price elasticity of gasoline demand. Users' travel demand can be changed by making them more aware of the fuel costs of different routes. As a result of becoming informed about their petrol consumption cost prior to entering traffic congestion, users may take an alternative route, change their travel schedule, or decide not to travel at all. Without considering the change in the price elasticity of gasoline demand, this study estimates the effects of providing gasoline consumption information (GCI) on people's route choice behaviour, the influence of fuel price on the effectiveness...
A Second-Order Sliding Mode Observer for Fault Detection and Isolation of Turbocharged SI Engines, Article IEEE Transactions on Industrial Electronics ; Volume 62, Issue 12 , June , 2015 , Pages 7795-7803 ; 02780046 (ISSN) ; Vossoughi, G ; Alasty, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc 2015
This paper proposes a novel method for detection and isolation of wastegate (WG) faults in a turbocharged (TC) gasoline engine. This paper starts with a fault effect analysis on the WG faults, including WG stuck open and stuck closed, which is an early step in a detection strategy design. Then, a second-order sliding-mode observer (SOSMO) is proposed to capture the exhaust manifold dynamics. The observer uses experimentally validated engine models to estimate the WG position and a virtual force. The virtual force represents the external disturbances that disrupt the WG operation and enables the proposed SOSMO to estimate the WG position robust to the faults. Using this force, a detection and...
Sliding Mode Observers to Detect and Isolate Faults in a Turbocharged Gasoline Engine, Article SAE International Journal of Engines ; Volume 8, Issue 2 , April , 2015 , Pages 399-410 ; 19463936 (ISSN) ; Alasty, A ; Vossoughi, G. R ; Sharif University of Technology
SAE International 2015
This paper presents a novel model-based algorithm which is able to detect and isolate major faults assigned to the gas exchange path of a gasoline engine both in the intake and exhaust sides. The diagnostics system is developed for detection and isolation of these faults: air leakage fault between the compressor and the air throttle, exhaust manifold pressure sensor fault, wastegate stuck-closed fault and wastegate stuck-open fault. Sliding mode observers (SMOs) are the core detection algorithms utilized in this work. A first order SMO is designed to estimate the turbocharger rotational dynamics. The wastegate displacement dynamics coupled to the exhaust manifold pressure dynamics is...
Beneficial Role of oxygen in co and propylene oxidation over a pt-pd-based wiremesh catalyst as a retrofit emission control device for four-stroke gasoline spark-ignited motorcycles, Article Energy and Fuels ; Volume 35, Issue 12 , 2021 , Pages 10122-10133 ; 08870624 (ISSN) ; Hamzehlouyan, T ; Hosseini, V ; Mayer, A ; Sharif University of Technology
American Chemical Society 2021
Over 200 million motorcycles in use worldwide account for a substantial portion of global mobile source total hydrocarbons (THC) and carbon monoxide (CO) emissions. In Tehran, capital of Iran, ultrarich inefficient combustion in gasoline-fueled motorcycles results in significantly high CO and THC emissions. Motorcycle catalysts can reduce CO and C3H6(as a representative hydrocarbon) emission factors by 60-80%. In the present work, CO and propylene oxidation over a commercial Pt-Pd-based wiremesh catalyst is studied in a flow reactor setup under simulated conditions relevant to 125 cc four-stroke gasoline carburetor motorcycles. Steady-state individual and co-oxidation tests for CO and...
Projection of passenger cars’ fuel demand and greenhouse gas emissions in Iran by 2050, Article Energy Conversion and Management: X ; Volume 12 , 2021 ; 25901745 (ISSN) ; Maleki, A ; Sharif University of Technology
Elsevier Ltd 2021
Passenger cars (PCs) not only are a major contributor to greenhouse gas (GHG) emissions in Iran but also pose severe energy security challenges due to their dependence on gasoline. This study aimed to understand the future trends of the gasoline demand and GHG emissions from PCs in Iran and assess the effectiveness of mitigation policies. The data were collected from multiple sources and used to develop the survival rate function of PCs. The study used back-calculation to compensate for the short period of stock data availability. The use intensity of PCs was estimated based on the gasoline consumption statistics. Econometric models were developed to project the future PC stock and use...
The Study of the Photocatalytic Effect of ZSM-5 Zeolite, M.Sc. Thesis Sharif University of Technology ; Ghanbari, Bahram
In this study, different metal oxides were impregnated on the surface of ZSM-5 employed as photocatalysis for degradation of methylene blue dye used in the presence of ultraviolet light. The final products were characterized by powder X-ray diffraction (XRD) and fourier transform infrared (FT-IR) method. According to the proposed mechanism for the photocatalytic degradation of methylene blue based on these results, it was found that the reaction followed from the first-order mechanism. The results indicated that rate constant for pure ZSM-5 was 9.3〖 ₓ10〗^(-3) (min-1). Furthermore the impregnated ZSM-5 having 12% zinc oxide demonstrated the highest photocatalytic activity with rate constant...
Power Boost Limitations of the Gasoline Turbocharged Engine, M.Sc. Thesis Sharif University of Technology ; Hajilouy Benisi, Ali ; Mozafari, Ali Asghar
Nowadays internal combustion engines play an important role in the power generation as well as transportation fields all over the world. By using the turbocharger in internal combustion engine, more power is obtained in compare with aspirated engine having the same size, which is limited for gasoline engines. In this research, by a three-zone computer simulation code and experimental tests, the power boost limitations of the gasoline turbocharged engine are investigated. The results of single cylinder aspirated gasoline engine tests are used for validation the natural aspirated part of the code. For validating the turbocharged engine simulation, the results of a four cylinders gasoline...
Estimation of Gasoline Demand Elasticity in Iran, M.Sc. Thesis Sharif University of Technology ; Rahmati, Mohammad Hossein ; Vesal, Mohammad
The price elasticity of gasoline demand is a key parameter in evaluation of various policy options. However, most of the literature uses aggregate data to identify this elasticity. Temporal and spatial aggregation make elasticity estimates unreliable. We employ a unique dataset of all gasoline transactions in Iran during a four-month period around an unexpected exogenous price change to identify price elasticity. After controlling for date and individual fixed effects we estimate a robust significant price elasticity of -0.127. Aggregation of the same data by week, month, and city yields an estimate of -0.3 indicating a significant bias in earlier studies. We also identify a significant...