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Spray characteristics and atomization behavior of bio-diesel (Norouzak) and diesel fuel blends
, Article Particulate Science and Technology ; 2016 , Pages 1-12 ; 02726351 (ISSN) ; Jafari, M ; Ahari, M ; Saidi, M. H ; Hajinezhad, A ; Mozaffari, A. A ; Sharif University of Technology
Taylor and Francis Inc
2016
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...
Transient modeling of dual fuel catalytic converter
, Article Iranian Journal of Science and Technology, Transaction B: Technology ; Volume 27, Issue 2 , 2003 , Pages 291-298 ; 03601307 (ISSN) ; Kazemeini, M ; Badakhshan, A ; Soltanieh, M ; Estiri, M ; Sharif University of Technology
2003
Abstract
Exhaust gas emissions from mobile sources and its importance in urban pollution have currently attracted lots of interests towards studying on alternative fuel systems for road vehicles usage. One of the best replacements is the natural gas/diesel dual fuel, which offers an alternative to standard compression-ignition diesel engines. In the dual fuel system the primary fuel is natural gas, which may replace as much as 90% of the diesel fuel with a small amount of diesel fuel required ensuring effective ignition. Methane, the main constituent of natural gas, has high combustion efficiency. Dual fuel engines produce lower NOx emissions and fewer particulates. However, at moderate engine loads,...
Catalytic converter reducing dual fuel (natural gas/diesel) engine emissions
, Article Scientia Iranica ; Volume 6, Issue 5 , 2000 , Pages 75-81 ; 10263098 (ISSN) ; Kazemeini, M ; Soltanieh, M ; Checkel, M. D ; Badakhshan, A ; Zheng, M ; Mirosh, E. A ; Sharif University of Technology
Sharif University of Technology
2000
Abstract
Using natural gas combined with diesel fuel in diesel engines provides a considerable contribution to modern industrial societies in order to control air pollution and, also, generalize and facilitate the use of public vehicles. In spite of the attractive features of this idea, including reduction of NO(X) and particulates, there is an important burden imposed upon the system at low to intermediate torques, namely high concentration of CO and unburned total hydrocarbons (THC), mostly composed of methane. In this work, based upon the oxidation of CO and unburned HCs and through experimental results, application of a monolithic oxidizing bifunctional catalytic converter as a novel...
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...
Solid nanoparticle and gaseous emissions of a diesel engine with a diesel particulate filter and use of a high-sulphur diesel fuel and a medium-sulphur diesel fuel
, Article Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering ; Volume 231, Issue 7 , 2017 , Pages 941-951 ; 09544070 (ISSN) ; Hosseini, V ; Ehteram, M. A ; Sharif University of Technology
Abstract
High-sulphur and medium-sulphur diesel fuels are still used in several countries. Although diesel particulate filter technology for on-road diesel engines has existed since 1989, the availability of high-sulphur and medium-sulphur diesel fuels in the market causes delays in the use of catalysed filter technologies. However, the situation in places such as Tehran is considered unhealthy because of particles and black carbon, and full distribution of ultra-low-sulphur diesel is awaited eagerly. The purpose of this study is to investigate the effect of the sulphur content in fuels on the gaseous and solid exhaust emissions of a 220 kW Euro II engine equipped with a sintered metal active-passive...
Investigation of DPF-CRT Performance in Relation with Diesel Fuel Sulfur Content
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Vahid (Supervisor)
Abstract
Iran’s big cities air pollution is one of the major challenges to authorities in view of public health. Tehran City has been facing more and more air quality problems over the last decade. The criteria pollutants in Tehran are PM2.5, PM10. Particulates and especially ultrafine particles have been identified as the most toxic component of the polluting mixture. Considering diesel engine operation concepts, these types of engines are one of the main source emission of ultrafine particles, with more than 58%, in Tehran. So controlling particulates emitted from these sources, is one of the first steps to improve air quality. Diesel Particulate Filters (DPFs) are well-known and effective way to...
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...
Performance investigation of a four stroke diesel engine, using water-based ferrofluid as an additive
, Article ASME 2011 International Mechanical Engineering Congress and Exposition, IMECE 2011, 11 November 2011 through 17 November 2011 ; Volume 4, Issue PARTS A AND B , November , 2011 , Pages 1339-1343 ; 9780791854907 (ISBN) ; Jahani, N ; Shafii, M. B ; ASME ; Sharif University of Technology
Abstract
In this experimental study, a four stroke diesel engine was conducted to investigate the effect of adding water-based ferrofluid to diesel fuel on engine performance. To our knowledge, Magnetic nanoparticles had not been used before. To this end, emulsified diesel fuels of 0, 0.4, and 0.8 water-based ferrofluid/Diesel ratios by volume were used as fuel. The ferrofluid used in this study was a handmade water-based ferrofluid prepared by the authors. The results show that adding water-based ferrofluid to diesel fuel has a perceptible effect on engine performance, increasing the brake thermal efficiency relatively up to 12%, and decreasing the brake specific fuel consumption relatively up to...
Modeling of pressure line behavior of a common rail diesel engine due to injection and fuel variation
, Article Journal of the Brazilian Society of Mechanical Sciences and Engineering ; Volume 39, Issue 3 , 2017 , Pages 661-669 ; 16785878 (ISSN) ; Aziz, A. A ; Hamidi, A ; Hajialimohammadi, A ; Hosseini, V ; Sharif University of Technology
Springer Verlag
2017
Abstract
Common rail diesel engines with electronic fuel injection can accurately meter the fuel injection quantity with more accurate fuel injection control capability. In this work a common rail fuel injection system of a single cylinder diesel engine has been proposed and the important parameters like injection pressure, energizing time and high pressure pipes diameter and length are designed such that to be compatible with the engine basic design in case of pressure waves and injected mass variations. A one-dimensional approach has been used to model the injector using AMESim code in which Adiabatic models have been used to model injector system. Injected mass quantity has been calculated for...
Three-phase Model for a Fixed-bed Laboratory Scale Diesel Hydrotreating Reactor
, M.Sc. Thesis Sharif University of Technology ; Khorasheh, Fahad (Supervisor) ; Sadighi, Sepehr (Supervisor)
Abstract
The harmful environmental effects of gases resulting from the combustion of sulfur compounds in fuel, poisoning of catalysts, corrosion of equipment, as well as the intensification of environmental considerations and new standards adopted for the maximum amount of sulfur, have made the desulfurization of fuels important; Meanwhile, the desulfurization method using hydrogen has a high potential to remove sulfur compounds. For example, diesel fuel contains a variety of impurities such as sulfur, nitrogen (basic and Non-basic), and aromatic compounds, the sulfur in diesel fuel causes many problems related to environmental pollution and corrosion of engine components. Also, due to the high...
Performance Simulation of HCCI Engine Equipped with Direct Injection System
, M.Sc. Thesis Sharif University of Technology ; Mozafari, Ali Asghar (Supervisor)
Abstract
HCCI engines have lower NOX and PM emissions and higher thermal efficiency compared to spark ignition engines. But these engines have some deficiencies which up to now have prevented their widespread employment. These engines have not been very successful at high loads and speeds and in these conditions normally produce high pollution and noise. In order to solve this problem the present research proposes to equip the HCCI engines with fuel injection system so that at low loads and speeds operate at HCCI engine mode and at loads and speeds higher than pre-set limits, use the fuel injection system in order to operate at a combined HCCI and compression ignition engine mode and provide a...
A predictive control of a turbocharged diesel engine for exhaust emission mitigation
, Article 41st Annual Conference of the IEEE Industrial Electronics Society, 9 November 2015 through 12 November 2015 ; 2015 , Pages 4890-4895 ; 9781479917624 (ISBN) ; Tahami, F ; IEEE Industrial Electonics Society (IES)
Institute of Electrical and Electronics Engineers Inc
Abstract
This paper investigates the control of diesel engines comprising two actuators: exhaust gas recirculation (EGR) valve and variable geometry turbocharger (VGT) to mitigate the exhaust emissions. In contrast to conventional control techniques, multi-model predictive control (MMPC) algorithm is employed for control purposes. With the help of proposed scheme, constraints of the control problem is also considered and nonlinear model to enhance performance is utilized. In doing so, new controller tries to fulfill a compromise between fuel consumption and torque response by regulating air-to-fuel ratio and EGR fraction to decrease pollutants emission especially nitrogen oxides (NOx). The dynamic...
GABIST: A new methodology to find near optimal LFSR for BIST structure
, Article 14th IEEE International Conference on Electronics, Circuits and Systems, ICECS 2007, Marrakech, 11 December 2007 through 14 December 2007 ; 2007 , Pages 1107-1110 ; 1424413788 (ISBN); 9781424413782 (ISBN) ; Salmani Jelodar, M ; Hessabi, S ; Sharif University of Technology
2007
Abstract
Fault coverage and test time have important roles in using Built in self-test (BIST). Two parameters are crucial and effective in BIST design: LFSR's polynomial (or configuration) and its initial seed. In this paper we propos a practical method for finding near optimal LFSR with genetic algorithm (GA) and show that LFSR is a good TPG compared with other TPGs. In this method, the candidate seeds are achieved through a deterministic approach, and an evolutionary approach is employed to obtain the LFSR configurations for the desired fault coverage under test time constraint. The configurations are encoded in binary chromosomes. The evolution process evolves the fittest configurations to achieve...
A review on the methods in diesel desulfurization
, Article Current Analytical Chemistry ; Volume 17, Issue 6 , 2021 , Pages 815-830 ; 15734110 (ISSN) ; Ahmad, S ; Tahir, Z ; Ul Hassan, S ; Ali, Z ; Akhtar, M. N ; Azam, K ; Abdullah, M. O ; Sharif University of Technology
Bentham Science Publishers
2021
Abstract
Background: Diesel mainly consists of paraffin and thio-aromatic compounds. Sulfur present in diesel exhaust is the major challenge for oil refineries. Sulfur is an oxidizing element that discharges as acute pollutant in the environment, having adverse effects on human and animal life. Introduction: The scope of this review paper is to discuss and highlight the recent advancements in the process of desulfurization of diesel oil to explore the less energy-intensive and more economical process. Methods: Recently, different techniques are widely used for desulfurization of diesel oil to remove sulfur containing compounds from diesel. These techniques mainly involve hydrodesulfurzation,...
Detailed analysis of the effects of biodiesel fraction increase on the combustion stability and characteristics of a reactivity‐ controlled compression ignition diesel‐biodiesel/natural gas engine
, Article Energies ; Volume 15, Issue 3 , 2022 ; 19961073 (ISSN) ; Hosseini, V ; Sharif University of Technology
MDPI
2022
Abstract
A single‐cylinder marine diesel engine was modified to be operated in reactivity controlled compression ignition (RCCI) combustion mode. The engine fueling system was upgraded to a common rail fuel injection system. Natural gas (NG) was used as port fuel injection, and a die-sel/sunflower methyl ester biodiesel mixture was used for direct fuel injection. The fraction of bio-diesel in the direct fuel injection was changed from 0% (B0; 0% biodiesel and 100% diesel) to 5% (B5) and 20% (B20) while keeping the total energy input into the engine constant. The objective was to understand the impacts of the increased biodiesel fraction on the combustion characteristics and stability, emissions, and...
Study potential of indigenous pseudomonas aeruginosa and bacillus subtilis in bioremediation of diesel-contaminated water
, Article Water, Air, and Soil Pollution ; Volume 228, Issue 1 , 2017 ; 00496979 (ISSN) ; Kariminia, H. R ; Ghobadi Nejad, Z ; Fletcher, T. H ; Sharif University of Technology
Abstract
Petroleum products which are used in a wide variety of industries as energy sources and raw materials have become a major concern in pollution of terrestrial and marine environments. The purpose of this study was to assess the potential of indigenous microbial isolates for degradation of diesel fuel. Two most proficient bacterial strains among five isolated strains from polluted soil of an industrial refinery were studied. The isolates then were identified as Pseudomonas aeruginosa and Bacillus subtilis using biochemical tests and 16S rRNA gene sequence analyses. P. aeruginosa showed higher biodegradation efficiency than B. subtilis in shaking flask containing diesel-contaminated water. P....
Black carbon and PM2.5 monitoring campaign on the roadside and residential urban background sites in the city of Tehran
, Article Atmospheric Environment ; Volume 218 , 2019 ; 13522310 (ISSN) ; Aliasghari, P ; Hosseini, V ; Sharif University of Technology
Elsevier Ltd
2019
Abstract
Fine particulate matter characterized as PM2.5 is the most important criteria air pollutant in the city of Tehran. Tehran is one of the most polluted cities of the Middle East based on annual mean PM2.5 concentrations. Tehran emission inventory shows the large contribution of mobile sources to the total particles. PM2.5 source apportionment studies show large fraction of black carbon (BC) in the total mass of PM2.5, especially during the cold seasons. BC is the product of incomplete combustion that is mainly derived from diesel engines and rich-burned gasoline carburetor engines on scooters and light-duty vehicles. The present study shows the results of a large experimental campaign in which...
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...
Using Experimental Results and a Multi-Zone HCCI Combustion Model to Develop a Surrogate Diesel Fuel Autoignition Mechanism
, M.Sc. Thesis Sharif University of Technology ; Hosseini, Vahid (Supervisor)
Abstract
Real fuels contain hundreds of hydrocarbons such as linear and chain paraffins, naphthenes, olefins and aromatics.Behavior of this real fuels are represented by mixtures with simple compounds. Since engine with homogeneous charge compression ignition (HCCI) is a promising combustion concept able to provide very low NOx and PM diesel engine emissions while keeping good fuel economy, for use in vehicles requires kinetic reaction mechanism to simulate the hydrocarbons oxidation and it’s rules.combustion control is facing with basic problem in this engine.unlike conventional methods, . HCCI combustion is a kinetically controlled process and start of combustion will be controlled and dominanted...
Enhancing the Stability of Nanoparticles Added to a Diesel-biodiesel Blend with the Aim of Improving the Properties of the Blend
, M.Sc. Thesis Sharif University of Technology ; Fotovat, Farzam (Supervisor)
Abstract
The gradual depletion of the resources of fossil fuels, as well as the instability of their price in addition to the necessity of mitigation of hazardous air pollutants, are the chief reasons to increase the use of renewable sources. Biodiesel, as one of the best alternatives, can mitigate the emission of air pollutants resulting from fuel combustion. However, using raw biodiesel is not economically viable due to its lower quality in comparison with diesel. In this study, the role of nanoparticles in the improvement of biodiesel characteristics has been investigated. Firstly, biodiesel was produced from waste cooking oil (WCO) using the transesterification reaction, and then ceria and...