Search for: fuel-injection
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
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...
An experimental study on combustion dynamics and NOx emission of a swirl stabilized combustor with secondary fuel injection, Article Journal of Thermal Science and Technology ; 2010 , Pages 266-281 ; 18805566 (ISSN) ; Farshchi, M ; Shimura, M ; Tanahashi, M ; Miyauchi, T ; Sharif University of Technology
To investigate the effects of flow rate, diameter and offset of secondary fuel injection on combustor noise level, pressure fluctuation and NOx emission, four types of injectors were examined in a swirl-stabilized combustor for overall equivalence ratio (Ø) of 0.7 ~ 0.9 and flow rate of secondary fuel (Qsec) from 0.6 to 4.2 L/min. As for the reference injector used in previous related studies, secondary fuel injection of 3.0 L/min is the best condition for the reduction of pressure fluctuation and combustion noise with tolerable NOx emission. For lower secondary fuel rate of 1.8 L/min, reduction of the injection diameter of reference injector results in a better performance in terms of...
M.Sc. Thesis Sharif University of Technology ; Morad, Mohammad Reza
With increasing demand for more efficient combustion processes, alternative processes like application of magnetic and electric fields for modification of combustion have offered possible solutions. In the recent years, liquid electro-spraying has been a hot topic with growing interest due to its wide applications in such area as fuel atomization in combustion systems, which has been investigated in this project. Notice that in this method the liquid fuel in the high voltage electric field between electrodes will be broken into small droplets. In this thesis diffusion combustion of two alcoholic liquid fuels of ethanol and butanol at the exit of a small-scale combustor of vertical Pyrex...
M.Sc. Thesis Sharif University of Technology ; Farshchi, Mohammad
Turbine engines performance is notably dependent on environmental conditions, i.e. pressure and temperature and also on flight speed. Every engine has a specific flight ceiling, i.e. altitude above which engine shuts down. Engine shut down during altitude increase, is because of combustor performance loss and its efficiency and stability decrease. Combustor stability limit can be extended by performing modifications such as replacing fuel injectors and/or improving fuel characteristics, and the combustor can be used for higher altitude whitout any required change in design. In this thesis, influence of combustor various parameters like air flow rate, fuel equivalence ratio, inlet pressure...
Ph.D. Dissertation Sharif University of Technology ; Farshchi, Mohammad
This thesis is a complementary experimental and theoretical investigation on stability of premixed flames and a study of combustion instability and combustion dynamics in a swirl-stabilized combustor, aiming to understand the fundamental mechanisms responsible for combustion oscillations in gas turbine combustors. Theoretical investigations on acoustic modeling of a simple combustor and a study on kinematic response of premixed flames to flow perturbations have been discussed in the first part of this work. In another part of thesis, experimental studies on the response of premixed flames to acoustic perturbations have been performed. In addition, experimental investigations on combustion...
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
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...
M.Sc. Thesis Sharif University of Technology ; Saeedi, Mohammad Hassan
With the increasing number of applications in internal combustion engines, environmental impact and air pollution caused by emissions has been much attention. Natural gas is a promising fuel for limiting pollution laws in many countries. The use of fuel with a higher ratio of hydrogen gas to carbon pollution reduction motor. In this context and with regard to development policy and also due to the diversity basket NGV fuel, fuel injection, has been modeled analytically and numerically in a direct injection engine. In this study, an analytical model for spray injection fuel delivery and is dissolved. The resolution of the method of separation of variables is taken. The effect of the nozzle...
Article Aerospace Science and Technology ; Volume 82-83 , 2018 , Pages 32-37 ; 12709638 (ISSN) ; Olyaei, G ; Sharif University of Technology
Elsevier Masson SAS 2018
After proposing a semi-analytical solution for swirl laminar flow, macroscopic characteristics of open-end pressure-swirl injector including discharge coefficient and spray cone angle are calculated. In the presence of air core of the axial region inside the injector, the laminar rotational flow equations are simplified, and with the assumption of the quasi-developed axial flow along the nozzle, the equations are iteratively solved employing separation of variables method. The accuracy of the proposed semi-analytical solution is compared by some numerical and experimental results on an open-end injector. The validity of quasi-developed flow defined in the present work is confirmed based on...
M.Sc. Thesis Sharif University of Technology ; Farshchi, Mohammad
Annular combustion chambers used in small turbine motors which incorporate centrifugal (rotary) injectors for injecting fuel, are known as Slinger combustion chambers. The Slinger injector works in such a way that fuel enters from an inner tube in motor shaft and exits with high pressure from the holes on the cylinder connected to the shaft. Because of the high centrifugal force, the fuel is sprayed with high quality after entering the combustion chamber. Type and angle of spray, fuel-air mixing type, combustion phenomena and flame stability makes this different than other annular combustion chambers. The process of combustion in the Slinger chamber of YJ402 motor is numerically simulated in...
Article IEEE Aerospace Conference Proceedings ; 2012 ; 1095323X (ISSN) ; 9781457705564 (ISBN) ; Morad, M. R ; Shakeri, A. R ; Sharif University of Technology
One of the most important subsystems in the air-breathing engines is the atomizers, which break the fuel into many droplets. It is well known that atomization quality has a significant influence on combustion characteristics such as stability limits, efficiency, and pollutant emission. Both jet and swirl injectors are applicable in gas turbine engines. The latter have been widely used for combustion chambers and the former are usually employed for fuel injection in the afterburner part. Since experimental and numerical study of atomizers could be complex and costly, a design methodology of atomizers based on empirical relations is still very advantageous and effective in reducing...
Article 13th International Energy Conversion Engineering Conference, 27 July 2015 through 29 July 2015 ; July , 2015 ; 9781624103766 (ISBN) ; Ghafourizadeh, M ; Schneider, G. E ; Sharif University of Technology
American Institute of Aeronautics and Astronautics Inc, AIAA 2015
A gaseous-kerosene/air turbulent nonpremixed flame in a combustion chamber is simulated to investigate the effects of fuel-injector cone-angle on the pollutions of soot nano-particles, carbon monoxide, and carbon dioxide. We use a two-equation soot model in our studying, consider a detailed chemical scheme consisting of 121 species and 2613 elementary reactions, use the flamelet model, employ the presumed-shape probability density functions PDFs, apply the two-equation κ-ε turbulence model with round-jet corrections, and take into account the radiation effects assuming optically-thin flame in our numerical modeling. This research concentrates on investigating the impacts of kerosene injector...
Article 54th AIAA Aerospace Sciences Meeting, 2016, 4 January 2016 through 8 January 2016 ; 2016 ; 9781624103933 (ISBN) ; Ghafourizadeh, M ; Schneider, G. E ; Sharif University of Technology
American Institute of Aeronautics and Astronautics Inc, AIAA 2016
In this paper, the effects of a baffle plate on flame deflection and its throttling are investigated numerically in a combustor consuming jet propellant JP. We study the plate effects on the resulting soot volume fraction, soot particles diameter, mass fractions of carbon monoxide (CO), carbon dioxide (CO2), and benzene (C6H6). We use a two-equation turbulence model, a PAH-inception two-equation soot model imposing oxidation due to OH agents, a detailed chemical kinetic consisting of 121 species and 2613 elementary reactions, and the flamelet combustion model to perform the current study. We also take into account the turbulence-chemistry interaction using the presumed-shape probability...
Performance and emissions of a reactivity controlled light-duty diesel engine fueled with n-butanol-diesel and gasoline, Article Applied Thermal Engineering ; Volume 134 , April , 2018 , Pages 214-228 ; 13594311 (ISSN) ; Reyhanian, M ; Hosseini, V ; Muhamad Said, M. F ; Aziz, A. A ; Sharif University of Technology
Elsevier Ltd 2018
Reactivity Controlled Compression Ignition can be extended over a wide spectrum of fuels and is anticipated as a promising strategy in meeting current and future emission regulations. In this study, the effect of n-butanol addition on combustion characteristics and emissions in a reactivity controlled engine was investigated experimentally. Different ratios of butanol-diesel blends at different settings of EGR and premixed ratios were applied to a light duty diesel engine. The butanol-diesel blends were directly injected into the combustion chamber while gasoline was injected at the intake port. Combustion phasing was maintained at 2.7 °CA for all of test points by adjusting fuel injection...
Careful parameter study to enhance the effect of injecting heavy fuel oil into a crossflow using numerical approaches, Article ASME 2018 5th Joint US-European Fluids Engineering Division Summer Meeting, FEDSM 2018, 15 July 2018 through 20 July 2018 ; Volume 2 , July , 2018 ; 08888116 (ISSN) ; 9780791851562 (ISBN) ; Fatin, A ; Schneider, G.E ; Fluids Engineering Division ; Sharif University of Technology
American Society of Mechanical Engineers (ASME) 2018
The flow and spray parameters can have noticeable roles in heavy fuel oil (HFO) spray finesse. As known, the interaction between droplets and cross flow should be considered carefully in many different industrial applications such as the process burners and gas turbine combustors. So, it would be so important to investigate the effect of injecting HFO into a crossflow more subtly. In this work, the effects of various flow and spray parameters on the droplet breakup and dispersion parameters are investigated numerically using the finite-volume-element method. The numerical method consists of a number of different models to predict the droplets breakup and their dispersion into a cross flow...
Article Particle and Particle Systems Characterization ; Volume 25, Issue 5-6 , 2009 , Pages 454-464 ; 09340866 (ISSN) ; Soltani, M. R ; Ashjaee, M ; Morad, M. R ; Sharif University of Technology
A general regression neural network technique was applied to design optimization of a liquid-liquid coaxial swirl injector. Phase Doppler Anemometry measurements were used to train the neural network. A general regression neural network was employed to predict droplet velocity and Sauter mean diameter at any axial or radial position for the operating range of a liquid-liquid coaxial swirl injector. The results predicted by neural network agreed satisfactorily with the experimental data. A general performance map of the liquid-liquid coaxial swirl (LLCS) injector was generated by converting the predicted result to actual fuel/oxidizer ratios. © 2008 WILEY-VCH Verlag GmbH & Co. KGaA