Loading...
Search for:
diesel-engines
0.005 seconds
Total 87 records
Computing optimum bidding strategy of gencos using simulated annealing method
, Article 2006 IEEE International Conference on Industrial Technology, ICIT, Mumbai, 15 December 2006 through 17 December 2006 ; 2006 , Pages 2563-2568 ; 1424407265 (ISBN); 9781424407262 (ISBN) ; Ranjbar, A. M ; Shirani, A. R ; Sadati, N ; Sharif University of Technology
2006
Abstract
This paper describes a new method that uses Simulated Annealing (SA) method for analyzing the competition among Generating Companies (Gencos) where they have incomplete information about their opponents. Each Genco models its opponents with their generating cost coefficients. The proposed methodology employs the Supply Function Equilibrium (SFE) for modeling a Genco's bidding strategy. Gencos change their bidding strategies until Nash equilibrium points are obtained. Nash equilibrium constitutes a central solution concept in game theory. The task of detecting the Nash equilibria of a finite strategic game remains a challenging up-todate. This paper uses SA to compute Nash equilibria...
A fast algorithm for construction of minimum delay multicast trees in P2P networks
, Article 2006 International Symposium on Communications and Information Technologies, ISCIT, Bangkok, 18 October 2006 through 20 October 2006 ; 2006 , Pages 137-142 ; Firooz, M. H ; Pakravan, M. R ; Avanaki, A. N ; Sharif University of Technology
2006
Abstract
Peer to Peer networks have received considerable attention during the past decade and have been the focus of many research and development activities. New applications such as video streaming or gaming would benefit from multicast topologies and creating such trees in peer to peer networks is a challenging task. Proper multicast trees should minimize the traffic delay and bandwidth consumption. At the same time, construction of these trees should not be very complicated in terms of the required processing power so they can be implemented easily. The required time for construction of multicast trees should also be minimized and that helps with their adaptation to the dynamics of the network....
Principal component analysis using constructive neural networks
, Article 2007 International Joint Conference on Neural Networks, IJCNN 2007, Orlando, FL, 12 August 2007 through 17 August 2007 ; 2007 , Pages 558-562 ; 10987576 (ISSN) ; 142441380X (ISBN); 9781424413805 (ISBN) ; Seyedsalehi, S. A ; Noori Hosseini, M ; Sadati, N ; Sharif University of Technology
2007
Abstract
In this paper, a new constructive auto-associative neural network performing nonlinear principal component analysis is presented. The developed constructive neural network maps the data nonlinearly into its principal components and preserves the order of principal components at the same time. The weights of the neural network are trained by a combination of Back Propagation (BP) and Genetic Algorithm (GA) which accelerates the training process by preventing local minima. The performance of the proposed method was evaluated by means of two different experiments that illustrated its efficiency. ©2007 IEEE
Main System Investigation of Turbocharged Diesel Engine During Performance Upgrade
, M.Sc. Thesis Sharif University of Technology ; Hajilouy Benisi, Ali (Supervisor) ; Nouri Broujerdi, Ali (Supervisor)
Abstract
The internal combustion engine power is determined by the amount of fuel effectively burned inside the engine cylinders. On the other hand, the fuel consumption is proportional to the air mass that enters the cylinders in each cycle. Conventionally, incoming the engine inlet air is at ambient conditions. However, with higher air density, the engine power increases for the same dimensions, so-called turbocharging. Although the engine's structure remains unchanged, it may be necessary to adjust the main systems of the engine simultaneously. This research investigated maximizing the power of a turbocharged diesel engine based on upgrading the degree of turbocharging. For this purpose, the EM355...
Optimal experiment design for plasma thermal spray parameters at bending loads
, Article International Journal of Surface Science and Engineering ; Volume 6, Issue 1-2 , 2012 , Pages 3-14 ; 1749785X (ISSN) ; Moridi, A ; Farrahi, G. H ; Sharif University of Technology
2012
Abstract
Ceramic thermal barrier coatings are applied on gas turbines and diesel engine components to protect metals from heat and this enhances the service lifetime by means of a reduction in working temperature. In the present paper, optimisation of plasma thermal spray parameters, including feed rate and nozzle distance from the specimen surface is performed by using the design of experiment method. Due to factorial approach, by considering two parameters with three variation levels, nine experiments of bending test are needed. The base material is cast aluminium alloy, A356.0-T7. The coating layers consist of a bond coat, Ni-Cr-Al-Y with a thickness of 150 μm and a top coat, ZrO2-8wt%Y2O3 with a...
The effect of diethyl ether addition on performance and emission of a reactivity controlled compression ignition engine fueled with ethanol and diesel
, Article Energy Conversion and Management ; Volume 174 , 2018 , Pages 779-792 ; 01968904 (ISSN) ; Reyhanian, M ; Hosseini, V ; Said, M. F. M ; Abdul Aziz, A ; Sharif University of Technology
Elsevier Ltd
2018
Abstract
Reactivity controlled compression ignition has been introduced to implement controllable, clean, and high thermal efficiency without undermining the advantages of premixed combustion. However, simultaneous auto-ignition introduced by reactivity controlled combustion challenges the combustion under higher load operations. This experimental study incorporates a dual phase heat release concept with the purpose of improving the performance of reactivity controlled compression ignition engine. Different ratios of ethanol/diethyl-ether blends (from 0% to 40% diethyl ether and 70% premixed ratio) were applied to a light duty diesel engine at various combustion timings and engine loads. The diesel...
Spray characteristics and atomization behavior of bio-diesel (Norouzak) and diesel fuel blends
, Article Particulate Science and Technology ; Volume 36, Issue 3 , 2018 , Pages 270-281 ; 02726351 (ISSN) ; Jafari, M ; Ahari, M ; Saidi, M. H ; Hajinezhad, A ; Mozaffari, A. A ; Sharif University of Technology
Taylor and Francis Inc
2018
Abstract
Norouzak oil seeds that are the source of bio-diesel (Norouzak) fuel grow mostly in Gonabad and Kashmar located in Khorasan, north east of Iran. Spray characteristics of Norouzak bio-diesel have been experimentally and theoretically studied in this work. Norouzak fuel is added to the conventional diesel fuel, and mixture formations of several blends have been investigated and compared with each other. Moreover, by varying ambient and injection conditions, behaviors of spray of different blends have been explored. Microscopic and macroscopic properties of spray such as Sauter Mean Diameter (SMD), Ohnesorge number, spray tip penetration, spray cone angle, spray projected area and volume have...
Investigating the Performance of Non-Catalyzed Diesel Particulate Filters Operating in Real World Driving Conditions
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Vahid (Supervisor) ; Kazemzadeh Hannani, Siamak (Co-Advisor)
Abstract
Studies in recent years show that more than 57% of all suspended particles released from stationary and mobile sources in Tehran are from diesel vehicles. Reducing the release of this pollutant can be very effective in improving the air condition of Tehran. At the moment, Diesel Particulate Filters (DPF) are considered as the most effective and available technology to reduce particulate emissions from diesel engine exhaust. In this research, the results of the tests on two types of non-catalyzed DPFs under Iran’s conditions have been analyzed. In the motor test, the efficiency of the filters is monitored in the state of operation with the engine representing the country's diesel engines and...
Engine Exhaust Temperature Control By Throttling
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Vahid (Supervisor)
Abstract
Diesel particulate filters (DPFs) are used in active and passive regeneration exhaust systems in order to reduce the soot emission of diesel engines. Soot regeneration process initiates at a certain minimum temperature. In Compression Ignition (CI) engines, the intake is not throttled usually, and load control is carried out by adjusting the amount of fuel injected into the cylinders. Consequently in low load working condition, as the fuel mass decreases, the air to fuel ratio increases that results in lowered exhaust gas temperature. On the other hand, passive regeneration strategies alone are not enough and it should be backed up by an active regeneration system in order to guarantee...
Impact of Oxygen-enriched Air Combustion by Membrane System on Performance of Diesel Engine and Air Pollutants Emission
, M.Sc. Thesis Sharif University of Technology ; Soltanieh, Mohammad (Supervisor)
Abstract
Oxygen enriched combustion is one of the attractive combustion technologies to control pollution and improve combustion in diesel engines. In the present work after an introduction to membrane seperation and membrane seperators for oxygen-nitrogen from air, a simulation of combustion chamber by GT-Power and membrane COMSOL Multiphysics was used to study the impact of oxygen enrichment on combustion, pollution and performance parameters with 23, 25 and 27% levels of enrichment. Increasing the oxygen engine content with the air leads to faster burn rates and the ability to burn more fuel at the same stoichiometry. These effects have the potential to decrease specific fuel consumption and...
NOx Reduction from the Exhaust Gas of Marine Diesel Engines Using Non-Thermal Plasma
, M.Sc. Thesis Sharif University of Technology ; Borghei, Mehdi (Supervisor) ; Hamzehlouyan, Tayebeh (Supervisor) ; Hajjar, Zeinab (Supervisor) ; Khani, Mohammad Reza (Supervisor)
Abstract
Environmental regulations with respect to the marine diesel emissions have become stricter during recent years, thereby imposing traffic limitations on Iranian ships preventing them to enter emission control areas. Nitrogen oxides (NOx), as one of most important air pollutants, have adverse impacts on public health and ecosystem, so as the ships are the primary source of NOx internationally, the after-treatment system finds more urge to be developed. In this study, a NOx reduction system using non-thermal plasma technology is studied in order to determine its application and efficiency for NOx removal from the exhaust gas of Iranian marine diesel engines. Meanwhile, important factors were...
Investigation of the Power Limits of a Turbocharged Diesel Engine based on its Mechanical Structure
, M.Sc. Thesis Sharif University of Technology ; Hajilouy Benisi, Ali (Supervisor) ; Zohoor, Hassan (Supervisor)
Abstract
With the global population increase, the fossil fuel consumption rate is rising. Issues of energy aspects and environment pollution have received more attention than before. In this regard, internal combustion engines play an essential role. By improving the performance these, it is possible to reduce their specific fuel consumption. Also, with the development of various industries, their required power is increasing, and providing a new engine with higher power and better performance needs high investment. While, providing this requirement by improving the performance of the existing engine costs much less. Considering that internal combustion engines, especially diesel engines, are used in...
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
Abstract
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...
On-line fault detection and isolation (FDI) for the exhaust path of a turbocharged SI engine
, Article ASME 2013 Dynamic Systems and Control Conference, DSCC 2013 ; Vol. 1 , 2013 ; ISBN: 9780791856123 ; Shahbakhti M ; Alasty, A ; Vossoughi, G ; Sharif University of Technology
Abstract
Detection and isolation of faults in the exhaust gas path of a turbocharged spark ignition (SI) engine is an essential part of the engine control unit (ECU) strategies to minimize exhaust emission and ensure safe operation of a turbocharger. This paper proposes a novel physics-based strategy to detect and isolate an exhaust manifold leakage and a closed-stuck wastegate fault. The strategy is based on a globally optimal parameter estimation algorithm which detects an effective hole area in the exhaust manifold. The estimation algorithm requires prediction of the exhaust manifold's input and output flows. The input flow is predicted by a nonlinear Luenberger observer which is analytically...
System modeling and optimization for islanded micro-grid using multi-cross learning-based chaotic differential evolution algorithm
, Article International Journal of Electrical Power and Energy Systems ; Vol. 56 , 2014 , pp. 349-360 ; ISSN: 01420615 ; Amjady, N ; Ehsan, M ; Sharif University of Technology
Abstract
This paper presents a comprehensive operation model for micro-grids (MG) operating in the islanded mode. Various energy sources of a MG including diesel engine generator, micro-turbine, wind turbine and photovoltaic cell as well as battery storage and AC/DC rectifier/inverter are modeled in the proposed framework. Fuel costs, emission costs, and operation and maintenance (O&M) costs of these sources as well as their operating limits and characteristics are considered in the model. Furthermore, a new multi-cross learning-based chaotic differential evolution (MLCDE) algorithm is presented to solve the optimization problem of MG operation. The numerical results obtained from the proposed...
Investigation into the effect of intake port geometric parameters and blockage on flow coefficient and in-cylinder flow: Application to engine port design
, Article Scientia Iranica ; Vol. 21, issue. 2 , 2014 , pp. 438-448 ; ISSN: 10263098 ; Kazemzadeh Hannani, S ; Shafii, B ; Sharif University of Technology
Abstract
The Computational Fluid Dynamics (CFD) method is employed to gain further insight into the characteristics of the in-cylinder flow field. Comparison between the measured and predicted results of the in-cylinder tumble flow and flow coefficient generated by a port-valve-liner assembly, on a steady-flow test bench, is presented, and a reasonably good level of agreement is achieved. A CAD parametric model of port geometry is created to enable variations, practically and quickly. Employing CFD analysis, the relationship between design parameters and port flow characteristics is established. The inuence of new blockage patterns on in-cylinder flow is also studied
A review of ignition delay and combustion characteristics of biodiesel fueled diesel engine
, Article Applied Mechanics and Materials ; Volume 390 , 2013 , Pages 333-337 ; 16609336 (ISSN) ; 9783037858332 (ISBN) ; Pourabdian, M ; Javareshkian, A ; Farzbod, A ; Sharif University of Technology
2013
Abstract
Increasing rate of demanding biodiesel as alternative energy resource, persuade researchers to investigate engine performance of biodiesel-fueled engines, which are highly influenced by ignition delay (ID) and combustion characteristics of such a fuel. This review article introduces a literature review on ignition delay (ID) and combustion characteristics of diesel engine fueled with biodiesel. Slightly difference between combustion characteristics of bio fueled engine and petroleum diesel one recognized as result of carried out investigations. Early start of combustion (SOC) and shorter ID of biodiesel comparing to diesel is reported by most of investigations. Lower compressibility, higher...
On-line fault detection and isolation (FDI) for the exhaust path of a turbocharged SI engine
, Article ASME 2013 Dynamic Systems and Control Conference, DSCC 2013 ; Volume 1 , 2013 ; 9780791856123 (ISBN) ; Shahbakhti, M ; Alasty, A ; Vossoughi, G ; Sharif University of Technology
2013
Abstract
Detection and isolation of faults in the exhaust gas path of a turbocharged spark ignition (SI) engine is an essential part of the engine control unit (ECU) strategies to minimize exhaust emission and ensure safe operation of a turbocharger. This paper proposes a novel physics-based strategy to detect and isolate an exhaust manifold leakage and a closed-stuck wastegate fault. The strategy is based on a globally optimal parameter estimation algorithm which detects an effective hole area in the exhaust manifold. The estimation algorithm requires prediction of the exhaust manifold's input and output flows. The input flow is predicted by a nonlinear Luenberger observer which is analytically...
Performance and exhaust emission characteristics of a spark ignition engine operated with gasoline and CNG blend
, Article Proceedings of the Spring Technical Conference of the ASME Internal Combustion Engine Division ; 2012 , Pages 179-187 ; 15296598 (ISSN) ; 9780791844663 (ISBN) ; Hamidi, A. A ; Mozafari, A. A ; Sharif University of Technology
2012
Abstract
Using CNG as an additive for gasoline is a proper choice due to higher octane number of CNG enriched gasoline with respect to that of gasoline. As a result, it is possible to use gasoline with lower octane number in the engine. This would also mean the increase of compression ratio in SI engines resulting in higher performance and lower gasoline consumption. Over the years, the use of simulation codes to model the thermodynamic cycle of an internal combustion engine have developed tools for more efficient engine designs and fuel combustion. In this study, a thermodynamic cycle simulation of a conventional four-stroke spark-ignition engine has been developed. The model is used to study the...
Determining new baselines of wear material in diesel engines, using oil analysis results
, Article Applied Mechanics and Materials, 29 July 2011 through 31 July 2011 ; Volume 110-116 , July , 2012 , Pages 1059-1064 ; 16609336 (ISSN) ; 9783037852620 (ISBN) ; Sayyah, M ; Ramezani, S ; Sharif University of Technology
2012
Abstract
Oil analysis technique is used as predictive and proactive tools to identify the wear modes of rubbing parts and to diagnose the faults in machinery. In this paper, the wear behavior of diesel engines, especially on oil analysis, is studied based on condition data. In terms of analyzing historical data, descriptive statistics is used as data mining tools to find the relationship between condition factors of the machine and its final status. The equipments have been monitored in two different environments which are: plantation-forestry, and general construction. Based on this relationship a specific baseline is achieved for selected sets of equipment in their specific conditions. A striking...