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Journal articles on the topic 'Intake manifold modeling'
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1
Galambos, Stjepan, Nebojsa Nikolic, Dragan Ruzic, and Jovan Doric. "An approach to computational fluid dynamic air-flow simulation in the internal combustion engine intake manifold." Thermal Science 24, no. 1 Part A (2020): 127–36. http://dx.doi.org/10.2298/tsci180707063g.
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The subject of this paper is modeling of an intake manifold of a four-stroke IC engine using contemporary software tools. Virtual 3D CAD model of an intake manifold was designed based on a real intake manifold of a four-stroke IC engine. Based on the CAD model a 3D CFD model of the intake manifold was created. The modeling has been done with the purpose of simulation of the air flow inside the intake manifold in order to monitor values of the internal pressure during several seconds of the engine operation in three different operating points. Also, an experiment was conducted, which included measurements of intake manifold pressure in the same engine operating points in the course of a time interval of approximately the same duration. The results of both the simulation and the experimental measurements have been shown in the paper proving that the created model was good enough for the intended purpose.
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Thompson, S., and C. Gong. "Intake Manifold Modeling for the Fuel Metering Control of Spark Ignited Engines." Journal of Dynamic Systems, Measurement, and Control 119, no. 3 (1997): 568–73. http://dx.doi.org/10.1115/1.2801296.
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In order to minimize emissions the Air-Fuel Ratio (AFR) of a spark-ignited internal combustion engine needs to be maintained at stoichiometric. Whenever the air and fuel enter the engine’s cylinder the AFR cannot be changed; therefore the problem of AFR control is a problem of intake manifold control. Although the problem of AFR control (and hence of intake manifold modelling) appears to be solved for a fully warmed-up engine the problem of AFR control during the warm-up period remains. This paper addresses this problem by using a novel AFR control strategy, which can be based on a given intake manifold model, to test the AFR control of a partially warmed-up engine. The results of engine tests demonstrate that during the warm-up period tight AFR control is not possible using any of the intake manifold models developed for a fully warmed-up engine. This can only be the result of unmodeled dynamics in the intake manifold and it is therefore concluded that further work in the area of manifold modelling is required. Possible areas of model improvement are indicated.
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Gangopadhyay, Anupam, and Peter Meckl. "Modeling and Validation of a Lean Burn Natural Gas Engine." Journal of Dynamic Systems, Measurement, and Control 123, no. 3 (1998): 425–30. http://dx.doi.org/10.1115/1.1386790.
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In this paper, a control-oriented model of a medium-duty throttle-body natural gas engine is developed. The natural gas engine uses lean-burn technology without exhaust gas recirculation (EGR). The dynamic engine model differs from models of gasoline engines by including the natural gas fuel dynamics in the intake manifold. The model is based on a mean value concept and has three state variables: intake manifold pressure, fuel fraction in the intake manifold and the engine rotational speed. The resulting model has been validated in steady-state and transient operation over the usual operating range of the engine between 800 rpm and 2600 rpm with air/fuel ratios ranging between 18.0 and 24.0.
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Wu, Yuh Yih, Bo Chiuan Chen, and Anh Trung Tran. "Semi-Direct Injection Engine Modeling for Real Time Control." Advanced Materials Research 347-353 (October 2011): 2504–10. http://dx.doi.org/10.4028/www.scientific.net/amr.347-353.2504.
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The Semi-Direct Injection (SDI) system has been shown to improve small engine efficiency and exhaust by utilizing a lean burn method. In order to better understand how to more readily utilize the control systems in SDI engine, the real-time operation of an SDI engine was modeled. A charging model was developed by using a filling-and-emptying model to simulate air exchange in an engine, including varying the intake manifold structure. A single-zone model was applied to a combustion model and the effects of air/fuel ratio and swirl ratio on combustion duration were also considered. The calculated results of the intake manifold pressure, heat release rate, and cylinder pressure were compared with the experimental data. The results of this study show that this modeling process approximates reality.
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Sakowitz, A., S. Reifarth, M. Mihaescu, and L. Fuchs. "Modeling of EGR Mixing in an Engine Intake Manifold Using LES." Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles 69, no. 1 (2013): 167–76. http://dx.doi.org/10.2516/ogst/2013118.
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Bondar, Vladimir, Sergei Aliukov, Andrey Malozemov, and Arkaprava Das. "Mathematical Model of Thermodynamic Processes in the Intake Manifold of a Diesel Engine with Fuel and Water Injection." Energies 13, no. 17 (2020): 4315. http://dx.doi.org/10.3390/en13174315.
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The article presents the results of a study aimed at creating a mathematical model of thermodynamic processes in the intake manifold of a forced diesel engine, taking into account the features of simultaneous injection of fuel and water into the collector. In the course of the study, the tasks of developing a mathematical model were solved, it was implemented in the existing software for component simulation “Internal combustion engine research and development” (ICE RnD), created using the Modelica language, and verification was undertaken using the results of bench tests of diesel engines with injection fuel and water into the intake manifold. The mathematical model is based on a system of equations for the energy and mass balances of gases and includes detailed mathematical submodels of the processes of simultaneous evaporation of fuel and water in the intake manifold; it takes into account the effect of the evaporation of fuel and water on the parameters of the gas state in the intake manifold; it takes into account the influence of the state parameters of the working fluid in the intake manifold on the physical characteristics of fuel and water; it meets the principles of component modeling, since it does not contain parameters that are not related to the simulated component; it describes the process of simultaneous transfer of vapors and non-evaporated liquids between components; and it does not include empirical relationships requiring data on the dynamics of fuel evaporation under reference conditions. According to the results of a full-scale experiment, the adequacy of the mathematical model developed was confirmed. This model can be used to determine the rational design parameters of the fuel and water injection system, the adjusting parameters of the forced diesel engine that provide the required power, and economic indicators, taking into account the limitations on the magnitude of the mechanical and thermal loads of its parts.
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Elmoselhy, Salah A. M., Waleed F. Faris, and Hesham A. Rakha. "Validated Analytical Modeling of Diesel Engines Intake Manifold with a Flexible Crankshaft." Energies 14, no. 5 (2021): 1287. http://dx.doi.org/10.3390/en14051287.
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The flexibility of a crankshaft exhibits significant nonlinearities in the analysis of diesel engines performance, particularly at rotational speeds of around 2000 rpm. Given the explainable mathematical trends of the analytical model and the lack of available analytical modeling of the diesel engines intake manifold with a flexible crankshaft, the present study develops and validates such a model. In the present paper, the mass flow rate of air that goes from intake manifold into all the cylinders of the engine with a flexible crankshaft has been analytically modeled. The analytical models of the mass flow rate of air and gas speed dynamics have been validated using case studies and the ORNL and EPA Freeway standard drive cycles showing a relative error of 7.5% and 11%, respectively. Such values of relative error are on average less than those of widely recognized models in this field, such as the GT-Power and the CMEM, respectively. A simplified version for control applications of the developed models has been developed based on a sensitivity analysis. It has been found that the flexibility of a crankshaft decreases the mass flow rate of air that goes into cylinders, resulting in an unfavorable higher rate of exhaust emissions like CO. It has also been found that the pressure of the gas inside the cylinder during the intake stroke has four elements: a driving element (intake manifold pressure) and draining elements (vacuum pressure and flow losses and inertial effect of rotating mass). The element of the least effect amongst these four elements is the vacuum pressure that results from the piston’s inertia and acceleration. The element of the largest effect is the pressure drop that takes place in the cylinder because of the air/gas flow losses. These developed models are explainable and widely valid so that they can help in better analyzing the performance of diesel engines.
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Xie, Long, Harutoshi Ogai, and Yasuaki Inoue. "Modeling And Solving An Engine Intake Manifold With Turbo Charger For Predictive Control." Asian Journal of Control 8, no. 3 (2008): 210–18. http://dx.doi.org/10.1111/j.1934-6093.2006.tb00272.x.
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Li, Jing Hua, and Jiang Jiang Li. "Based on 3-D Modeling and Value Simulation of the Intake System in CNG." Advanced Materials Research 989-994 (July 2014): 3477–79. http://dx.doi.org/10.4028/www.scientific.net/amr.989-994.3477.
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The structure of the air intake system directly affect the combustion and heat load in each cylinder. In this paper, using the CFD experience can look the intake pipe gas flow as a 3-D compressed steady flow. It is easy to built a 3-D model grids with the help of GAMBIT software .Using the FLUENT soft software ,it is reasonable to get the the fluid velocity distribution in flow field , and calculate the fluid flowing quality at the exit of manifold, as well as analyze the inhomogeneity of the inlet air.
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Beroun, Stanislav, Pavel Brabec, Aleš Dittrich, Ondřej Dráb, and Tuan Nguyen Thanh. "Computational Modeling of the Liquid LPG Injection into the Suction Manifold of an SI Vehicle Engine." Applied Mechanics and Materials 390 (August 2013): 355–59. http://dx.doi.org/10.4028/www.scientific.net/amm.390.355.
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LPG is a very first-rate alternative fuel for a vehicle SI engine. By mixture formation using the injection of the gaseous LPG into suction manifold of the naturally aspirated SI engine the engine power is reduced to the original petrol engine power. This advantage is corrected by mixture formation using the liquid LPG injection into the intake air to the suction manifold. The paper deals with the computational modelling of the process on the liquid LPG injection, especially of the history LPG pressure and the LPG temperature before outlet nozzle. The calibration of the computational model has been performed by the experiment. The paper proposes the design precaution on the icing of the outside on the outlet nozzle.
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PIĄTKOWSKI, Piotr. "The impact of kinematics of the airflow on the efficiency of combustion process in piston engines." Combustion Engines 145, no. 2 (2011): 82–88. http://dx.doi.org/10.19206/ce-117105.
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The technical possibility of decreasing engine emissions and fuel consumption in relation to the increase in the usable engine parameters has been presented in the paper. The above problem relates to the dynamic and kinematic properties of airflow into the combustion chamber. The effect of swirl in the intake manifold that refers to the achieved engine operating parameters and emission level was presented in the paper. The included results of the experimental research of airflow swirl in the air intake model allowed getting answers related to the issues of flow resistance. The analysis of literature and the analysis of the modeling results led to conclusions about the theoretical and practical possibilities of flexible intake duct implementation.
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Butt, Qarab Raza, Aamer Iqbal Bhatti, Mohammed Rafiq Mufti, Mudassar Abbas Rizvi, and Irfan Awan. "Modeling and online parameter estimation of intake manifold in gasoline engines using sliding mode observer." Simulation Modelling Practice and Theory 32 (March 2013): 138–54. http://dx.doi.org/10.1016/j.simpat.2012.12.001.
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Zhang, G. Q., and D. N. Assanis. "Manifold Gas Dynamics Modeling and Its Coupling With Single-Cylinder Engine Models Using Simulink." Journal of Engineering for Gas Turbines and Power 125, no. 2 (2003): 563–71. http://dx.doi.org/10.1115/1.1560708.
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A flexible model for computing one-dimensional, unsteady manifold gas dynamics in single-cylinder spark-ignition and diesel engines has been developed. The numerical method applies an explicit, finite volume formulation and a shock-capturing total variation diminishing scheme. The numerical model has been validated against the method of characteristics for valve flows without combustion prior to coupling with combustion engine simulations. The coupling of the gas-dynamics model with single-cylinder, spark-ignition and diesel engine modules is accomplished using the graphical MATLAB-SIMULINK environment. Comparisons between predictions of the coupled model and measurements shows good agreement for both spark ignition and diesel engines. Parametric studies demonstrating the effect of varying the intake runner length on the volumetric efficiency of a diesel engine illustrate the model use.
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Moskwa, J. J., and J. K. Hedrick. "Modeling and Validation of Automotive Engines for Control Algorithm Development." Journal of Dynamic Systems, Measurement, and Control 114, no. 2 (1992): 278–85. http://dx.doi.org/10.1115/1.2896525.
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There is considerable interest in coordinated automotive engine/transmission control to smooth shifts, and for traction control of front wheel vehicles. This paper outlines a nonlinear dynamic engine model of a port fuel-injected engine, which can be used for control algorithm development. This engine model predicts the mean engine brake torque as a function of the engine controls (i.e., throttle angle, spark advance, fuel flow rate, and exhaust gas recirculation (E. G. R.) flow rate). The model has been experimentally validated for a specific engine, and includes: • intake manifold dynamics, • fuel delivery dynamics, and • process delays inherent in the four-stroke engine. This model is used in real time within a control algorithm, and for system simulation. Also, it is flexible enough to represent a family of spark ignition automotive engines, given some test and/or simulation data for setting parameters.
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Jeanneret, Bruno, Alice Guille Des Buttes, Jérémy Pelluet, Alan Keromnes, Serge Pélissier, and Luis Le Moyne. "Optimal Control of a Spark Ignition Engine Including Cold Start Operations for Consumption/Emissions Compromises." Applied Sciences 11, no. 3 (2021): 971. http://dx.doi.org/10.3390/app11030971.
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This study presents a semi-empirical modeling approach based on an extensive parametric study using a spark-ignition port-injection engine. The experimental results are used to derive engine-out emission models for each regulated pollutant (CO, HC, NOx) as a function of engine operating parameters. Such parameters include engine speed, intake manifold pressure, equivalence ratio, and spark advance. The proposed models provide accurate predictions over a large range of engine operating conditions. The adequate accuracy and low computational burden of the models are promising in the context of optimal control theory. Dynamic programming is applied in order to find the best operating parameters that define trade-off between fuel consumption and emissions over driving cycles.
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Tirkey, Jeevan, Hari Gupta, and Shailendra Shukla. "Integrated gas dynamic and thermodynamic computational modeling of multicylinder 4-stroke spark ignition engine using gasoline as a fuel." Thermal Science 13, no. 3 (2009): 113–30. http://dx.doi.org/10.2298/tsci0903113t.
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This paper presents a computational tool for the evaluation of engine performance and exhaust emissions for four stroke multi-cylinder spark ignition engine which uses gasoline as a fuel. Gas dynamics flow in multi-cylinder intake and exhaust systems are modeled by using one-dimensional unsteady compressible flow equations. The hyperbolic partial differential equations are transferred into a set of ordinary differential equations by using method of characteristics and solved by finite difference method. Compatibility relationships between local fluid velocity and sonic velocity are expressed in terms of Riemann variables, which are constant along the position characteristics. The equations are solved numerically by using rectangular grid in the flow direction and time. In this model nitric oxide concentration is predicted by using the rate kinetic model in the power cycle and along the exhaust pipes. Carbon monoxide is computed under chemical equilibrium condition and then empirical adjustment is made for kinetic behaviors based upon experimental results. A good agreement is obtained in the comparison of computed and experimental results of instantaneous cylinder pressure, manifold pressure and temperature, and nitric oxide and carbon monoxide emissions level.
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Galindo, José, Héctor Climent, Joaquín de la Morena, David González-Domínguez, Stéphane Guilain, and Thomas Besançon. "Experimental and modeling analysis on the optimization of combined VVT and EGR strategies in turbocharged direct-injection gasoline engines with VNT." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 235, no. 10-11 (2021): 2843–56. http://dx.doi.org/10.1177/09544070211004502.
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The combination of a growing number of complex technologies in internal combustion engines (ICE) is commonplace, due to the need of complying with the tight pollutant regulations and achieving high efficiencies. Hence the work of calibration engineers is led by a constant increase in degrees of freedom in ICE design. In this research work, a wide analysis on the optimization of combined variable valve timing (VVT) and exhaust gases recirculation (EGR) strategies is developed, in order to reduce fuel consumption in a EURO 6 1.3l 4-stroke 4-cylinder, gasoline, turbocharged, direct-injection engine, also equipped with a variable nozzle turbine (VNT). For that purpose, a methodology which combines 1D engine simulations with limited experimental work was applied. First, the data from 25 experimental tests distributed into three steady engine operating conditions was used to calibrate a 1D model. Then, modeling parametric studies were performed to optimize VVT and EGR parameters. A total of 150 cases were simulated for each operating point, in which VVT settings and EGR rate were varied at iso-air mass flow and iso-intake manifold temperature. The optimization was based on finding the configuration of VVT and EGR systems which maximizes the indicated efficiency. All different cases modeled were also evaluated in terms of pumping and heat losses. Moreover, a deep assessment of instantaneous pressure traces and mass flows in intake and exhaust valves was given, to provide insights about the optimization procedure. Finally, the findings obtained by simulation were compared with the results from a design of experiments (DOE) composed of more than 300 tests, and the impact on engine fuel consumption was analyzed.
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Burger, M., G. Klose, G. Rottenkolber, et al. "A Combined Eulerian and Lagrangian Method for Prediction of Evaporating Sprays." Journal of Engineering for Gas Turbines and Power 124, no. 3 (2002): 481–88. http://dx.doi.org/10.1115/1.1473153.
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Polydisperse sprays in complex three-dimensional flow systems are important in many technical applications. Numerical descriptions of sprays are used to achieve a fast and accurate prediction of complex two-phase flows. The Eulerian and Lagrangian methods are two essentially different approaches for the modeling of disperse two-phase flows. Both methods have been implemented into the same computational fluid dynamics package which is based on a three-dimensional body-fitted finite volume method. Considering sprays represented by a small number of droplet starting conditions, the Eulerian method is clearly superior in terms of computational efficiency. However, with respect to complex polydisperse sprays, the Lagrangian technique gives a higher accuracy. In addition, Lagrangian modeling of secondary effects such as spray-wall interaction enhances the physical description of the two-phase flow. Therefore, in the present approach the Eulerian and the Lagrangian methods have been combined in a hybrid method. The Eulerian method is used to determine a preliminary solution of the two-phase flow field. Subsequently, the Lagrangian method is employed to improve the accuracy of the first solution using detailed sets of initial conditions. Consequently, this combined approach improves the overall convergence behavior of the simulation. In the final section, the advantages of each method are discussed when predicting an evaporating spray in an intake manifold of an internal combustion engine.
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Balerna, Camillo, Marc-Philippe Neumann, Nicolò Robuschi, et al. "Time-Optimal Low-Level Control and Gearshift Strategies for the Formula 1 Hybrid Electric Powertrain." Energies 14, no. 1 (2020): 171. http://dx.doi.org/10.3390/en14010171.
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Today, Formula 1 race cars are equipped with complex hybrid electric powertrains that display significant cross-couplings between the internal combustion engine and the electrical energy recovery system. Given that a large number of these phenomena are strongly engine-speed dependent, not only the energy management but also the gearshift strategy significantly influence the achievable lap time for a given fuel and battery budget. Therefore, in this paper we propose a detailed low-level mathematical model of the Formula 1 powertrain suited for numerical optimization, and solve the time-optimal control problem in a computationally efficient way. First, we describe the powertrain dynamics by means of first principle modeling approaches and neural network techniques, with a strong focus on the low-level actuation of the internal combustion engine and its coupling with the energy recovery system. Next, we relax the integer decision variable related to the gearbox by applying outer convexification and solve the resulting optimization problem. Our results show that the energy consumption budgets not only influence the fuel mass flow and electric boosting operation, but also the gearshift strategy and the low-level engine operation, e.g., the intake manifold pressure evolution, the air-to-fuel ratio or the turbine waste-gate position.
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Sofianopoulos, Aimilios, Mozhgan Rahimi Boldaji, Benjamin Lawler, and Sotirios Mamalis. "Investigation of thermal stratification in premixed homogeneous charge compression ignition engines: A Large Eddy Simulation study." International Journal of Engine Research 20, no. 8-9 (2018): 931–44. http://dx.doi.org/10.1177/1468087418795525.
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The operating range of Homogeneous Charge Compression Ignition (HCCI) engines is limited to low and medium loads by high heat release rates. Negative valve overlap can be used to control ignition timing and heat release by diluting the mixture with residual gas and introducing thermal stratification. Cyclic variability in HCCI engines with NVO can result in reduced efficiency, unstable operation, and excessive pressure rise rates. Contrary to spark-ignition engines, where the sources of cyclic variability are well understood, there is a lack of understanding of the effects of turbulence on cyclic variability in HCCI engines and the dependence of cyclic variability on thermal stratification. A three-dimensional computational fluid dynamics (CFD) model of a 2.0L GM Ecotec engine cylinder, modified for HCCI combustion, was developed using Converge. Large Eddy Simulations (LES) were combined with detailed chemical kinetics for simulating the combustion process. Twenty consecutive cycles were simulated and the results were compared with individual cycle data of 300 consecutive experimental cycles. A verification approach based on the LES quality index indicated that this modeling framework can resolve more than 80% of the kinetic energy of the working fluid in the combustion chamber at the pre-ignition region. Lower cyclic variability was predicted by the LES model compared to the experiments. This difference is attributed to the resolution of the sub-grid velocity field, time averaging of the intake manifold pressure boundary conditions, and different variability in the equivalence ratio compared to the experimental data. Combustion phasing of each cycle was found to depend primarily on the bulk cylinder temperature, which agrees with established findings in the literature. Large cyclic variability of turbulent mixing and spatial distribution of temperature was predicted. However, both of these parameters were found to have a small effect on the cyclic variability of combustion phasing.
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Hall, Bevan, Greg Wheatley, and Mohammad Zaeimi. "On the Design of the Manifold for a Race Car." Periodica Polytechnica Mechanical Engineering 65, no. 2 (2021): 171–79. http://dx.doi.org/10.3311/ppme.17325.
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This paper involves the design and construction of the intake manifold system of the FSAE car including the air shroud, air filter, throttle body, restrictor plenum, fuel injectors, fuel rail and runners. To ensure the quality, the proposed system is designed based on the FSAE rules. The design process of the intake manifold system will consist of the usual engineering processes including computer modelling, Finite Element Analysis and finally Computational Fluid Dynamics testing in order to determine the validity of the model and to tune the design in order to obtain the optimum performance out of the intake manifold system as a whole.
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Faris, Waleed F., Hesham A. Rakha, and Salah A. M. Elmoselhy. "Supercharged diesel powertrain intake manifold analytical model." International Journal of Vehicle Systems Modelling and Testing 9, no. 1 (2014): 1. http://dx.doi.org/10.1504/ijvsmt.2014.059154.
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Xu, Shuonan, David Anderson, Mark Hoffman, Robert Prucka, and Zoran Filipi. "A phenomenological combustion analysis of a dual-fuel natural-gas diesel engine." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 231, no. 1 (2016): 66–83. http://dx.doi.org/10.1177/0954407016633337.
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Energy security concerns and an abundant supply of natural gas in the USA provide the impetus for engine designers to consider alternative gaseous fuels in the existing engines. The dual-fuel natural-gas diesel engine concept is attractive because of the minimal design changes, the ability to preserve a high compression ratio of the baseline diesel, and the lack of range anxiety. However, the increased complexity of a dual-fuel engine poses challenges, including the knock limit at a high load, the combustion instability at a low load, and the transient response of an engine with directly injected diesel fuel and port fuel injection of compressed natural gas upstream of the intake manifold. Predictive simulations of the complete engine system are an invaluable tool for investigations of these conditions and development of dual-fuel control strategies. This paper presents the development of a phenomenological combustion model of a heavy-duty dual-fuel engine, aided by insights from experimental data. Heat release analysis is carried out first, using the cylinder pressure data acquired with both diesel-only and dual-fuel (diesel and natural gas) combustion over a wide operating range. A diesel injection timing correlation based on the injector solenoid valve pulse widths is developed, enabling the diesel fuel start of injection to be detected without extra sensors on the fuel injection cam. The experimental heat release trends are obtained with a hybrid triple-Wiebe function for both diesel-only operation and dual-fuel operation. The ignition delay period of dual-fuel operation is examined and estimated with a predictive correlation using the concept of a pseudo-diesel equivalence ratio. A four-stage combustion mechanism is discussed, and it is shown that a triple-Wiebe function has the ability to represent all stages of dual-fuel combustion. This creates a critical building block for modeling a heavy-duty dual-fuel turbocharged engine system.
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Mohamad, Barhm, Jalics Karoly, and Andrei Zelentsov. "CFD MODELLING OF FORMULA STUDENT CAR INTAKE SYSTEM." Facta Universitatis, Series: Mechanical Engineering 18, no. 1 (2020): 153. http://dx.doi.org/10.22190/fume190509032m.
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Formula Student Car (FS) is an international race car design competition for students at universities of applied sciences and technical universities. The winning team is not the one that produces the fastest racing car, but the group that achieves the highest overall score in design, racing performance. The arrangement of internal components for example, predicting aerodynamics of the air intake system is crucial to optimizing car performance as speed changes. The air intake system consists of an inlet nozzle, throttle, restrictor, air box and cylinder suction pipes (runners). The paper deals with the use of CFD numerical simulations during the design and optimization of components. In this research article, two main steps are illustrated to develop carefully the design of the air box and match it with the suction pipe lengths to optimize torque over the entire range of operating speeds. Also the current intake system was assessed acoustically and simulated by means of 1-D gas dynamics using the software AVL-Boost. In this manner, before a new prototype intake manifold is built, the designer can save a substantial amount of time and resources. The results illustrate the improvement of simulation quality using the new models compared to the previous AVL-Boost models.The results illustrate the improvement of simulation quality using the new models compared to the previous AVL-Boost models.
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Chen, Song, and Fengjun Yan. "Decoupled disturbance rejection control for a turbocharged engine with a dual-loop exhaust gas recirculation system." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering 232, no. 5 (2017): 599–615. http://dx.doi.org/10.1177/0954407017704780.
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Dual-loop exhaust gas recirculation with a variable-geometry turbocharger is an effective architecture for achieving desired intake manifold conditions, such as the temperature, the pressure and the oxygen concentration of the intake manifold, which have critical roles in advanced combustion mode control. However, the widely used control-oriented model is derived on the basis that the heat transfer between the pipes and the gas is negligible, which means that it suffers from non-trivial errors. Simulation results show that other error sources, including the volumetric efficiency and the orifice equation, are difficult to calibrate accurately and also cause significant errors in the system, particularly in transient situations. Modified active disturbance rejection control with an extended state observer is utilized to deal with the non-linear, multiple-input multiple-output system in this paper. It is demonstrated that the performance of active disturbance rejection control mainly depends on the performance of the extended state observer. In this paper, an extended state observer, which is based on the sliding-mode concept rather than the conventional linear observer, is introduced. By taking advantage of its strong robustness, the system is decoupled into three loops. For each loop, the internal errors and the external errors, including the modelling error and the coupling effects, are lumped into one term; they are then actively estimated and cancelled out by the control input in real time. The proposed method was validated using calibrated GT-Power model simulations.
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Hu, Mengsu, and Jonny Rutqvist. "Microscale mechanical modeling of deformable geomaterials with dynamic contacts based on the numerical manifold method." Computational Geosciences 24, no. 5 (2020): 1783–97. http://dx.doi.org/10.1007/s10596-020-09992-z.
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Abstract Micromechanical modeling of geomaterials is challenging because of the complex geometry of discontinuities and potentially large number of deformable material bodies that contact each other dynamically. In this study, we have developed a numerical approach for micromechanical analysis of deformable geomaterials with dynamic contacts. In our approach, we detect contacts among multiple blocks with arbitrary shapes, enforce different contact constraints for three different contact states of separated, bonded, and sliding, and iterate within each time step to ensure convergence of contact states. With these features, we are able to simulate the dynamic contact evolution at the microscale for realistic geomaterials having arbitrary shapes of grains and interfaces. We demonstrate the capability with several examples, including a rough fracture with different geometric surface asperity characteristics, settling of clay aggregates, compaction of a loosely packed sand, and failure of an intact marble sample. With our model, we are able to accurately analyze (1) large displacements and/or deformation, (2) the process of high stress accumulated at contact areas, (3) the failure of a mineral cemented rock samples under high stress, and (4) post-failure fragmentation. The analysis highlights the importance of accurately capturing (1) the sequential evolution of geomaterials responding to stress as motion, deformation, and high stress; (2) large geometric features outside the norms (such as large asperities and sharp corners) as such features can dominate the micromechanical behavior; and (3) different mechanical behavior between loosely packed and tightly packed granular systems.
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Shin, Hyunki, Donghyuk Jung, Manbae Han, Seungwoo Hong, and Donghee Han. "Minimization of Torque Deviation of Cylinder Deactivation Engine through 48V Mild-Hybrid Starter-Generator Control." Sensors 21, no. 4 (2021): 1432. http://dx.doi.org/10.3390/s21041432.
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Cylinder deactivation (CDA) is an effective technique to improve fuel economy in spark ignition (SI) engines. This technique enhances volumetric efficiency and reduces throttling loss. However, practical implementation is restricted due to torque fluctuations between individual cylinders that cause noise, vibration, and harshness (NVH) issues. To ease torque deviation of the CDA, we propose an in-cylinder pressure based 48V mild-hybrid starter-generator (MHSG) control strategy. The target engine realizes CDA with a specialized engine configuration of separated intake manifolds to independently control the airflow into the cylinders. To handle the complexity of the combined CDA and mild-hybrid system, GT-POWER simulation environment was integrated with a SI turbulent combustion model and 48V MHSG model with actual part specifications. The combustion model is essential for in-cylinder pressure-based control; thus, it is calibrated with actual engine experimental data. The modeling results demonstrate the precise accuracy of the engine cylinder pressures and of quantities such as MAF, MAP, BMEP, and IMEP. The proposed control algorithm also showed remarkable control performance, achieved by instantaneous torque calculation and dynamic compensation, with a 99% maximum reduction rate of engine torque deviation under target CDA operations.
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Ogawa, H., N. Miyamoto, N. Kaneko, and H. Ando. "Combustion control and operating range expansion in an homogeneous charge compression ignition engine with direct in-cylinder injection of reaction inhibitors." International Journal of Engine Research 6, no. 4 (2005): 341–59. http://dx.doi.org/10.1243/146808705x30440.
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Light naphtha, which exhibits two-stage ignition, was induced from the intake manifold and water or a low-ignitability fuel, which does not exhibit low temperature oxidation, was directly injected early in the compression stroke for ignition suppression in an homogeneous charge compression ignition (HCCI) engine. Their quantitative balance was flexibly controlled to optimize ignition timing according to operating conditions. Ultra-low NOx and smokeless combustion without knocking or misfiring was realized over a wide operating range with water or alcohol injection. The water injection significantly reduced the low-temperature oxidation, which suppressed the increase in charge temperature and the rapid combustion caused by the high-temperature oxidation. Rapid combustion was suppressed by reductions in the maximum in-cylinder gas temperature due to water injection while the combustion efficiency suffered. Therefore, the maximum charge temperature needs to be controlled within an extremely limited range to maintain a satisfactory compromise between mild combustion and high combustion efficiency. Alcohols inhibit low-temperature oxidation more strongly than other oxygenated or unoxygenated hydrocarbons, water, and hydrogen. Chemical kinetic modelling with methanol showed a reduction of OH radical before the onset of low-temperature oxidation, and this may be the main mechanism by which alcohols inhibit low-temperature oxidation.
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Cárdenas-Escorcia, Yulineth, Guillermo Valencia-Ochoa, and Juan Campos-Avella. "Fault Detection using Principal Component Analysis and Mean Value Modeling in a 2 MW gas engine." Respuestas 25, no. 1 (2020): 15–24. http://dx.doi.org/10.22463/0122820x.2401.
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This paper describes the combination of statistical techniques and mathematical modeling in order to developed a fault detection system in a 2 MW natural gas engine under actual operation conditions. The Mixing chamber, turbochargers, intake and exhaust manifolds, cylinders, throttle and bypass valves, and the electric generator, which are the main components of the gas engine, were studied under a mean value engine to complement the statistical analysis. Objective: The main objective of this paper is to integrate two approaches in order to relate the faults with the changes of mean thermodynamic values of the system, helping to sustain the engine in optimal operating conditions in terms of reliability. The Principal Component Analysis (PCA), a multivariate statistical fault detection technique, was used to analyze the historical data from the gas engine to detect abnormal operation conditions, by means of statistical measures such as Square Prediction Error (SPE) and T2. These abnormal operation conditions are categorized using cluster techniques and contributions plots, to later examine its causes with the support of the results of a mean value mathematical model proposed for the system. The integration of the proposed methods allowed successfully identify which component or components of the engine might be malfunctioning. Once combined, these two methods were able to accurately predict and identify faults as well as shut downs of the gas engine during a month of operation. Statistical analysis was used to detect faults on a 2 MW industrial gas engine, also the result were compared with a mean value model in order to detect variations of the thermodynamic properties of the system at abnormal conditions.
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Dilibe, Ifeanyi. "Computational model of the fuel consumption and exhaust temperature of a heavy duty diesel engine using MATLAB/SIMULINK." Poljoprivredna tehnika 45, no. 4 (2020): 51–70. http://dx.doi.org/10.5937/poljteh2004051d.
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A model of a diesel engine and its electronic control system was developed to investigate the engine behaviour in a vehicle simulation environment. The modelled quantities were brake torque, fuel consumption and exhaust gas temperature and were based on engine speed and pedal position. In order to describe these outputs the inlet air flow and boost pressure were also modelled and used as inner variables. The model was intended to be implemented on board a vehicle in a control unit which had limited computational performance. To keep the model as computationally efficient as possible the model basically consists of look-up tables and polynomials. First order systems were used to describe the dynamics of air flow and exhaust temperature. The outputs enable gear shift optimization over three variables, torque for vehicle acceleration, fuel consumption for efficiency and exhaust temperature to maintain high efficiency in the exhaust after treatment system. The engine model captures the low frequent dynamics of the modelled quantities in the closed loop of the engine and its electronic control system. The model only consists of three states, one for the pressure build up in the intake manifold and two states for modelling the exhaust temperature. The model was compared to measured data from an engine test cell (as got in INNOSON NIG. LTD.) and the mean absolute relative error were lower than 6.8%, 7.8% and 5.8% for brake torque, fuel consumption and exhaust gas temperature respectively. These results were considered good given the simplicity of the model.
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Shingne, Prasad S., Robert J. Middleton, Dennis N. Assanis, Claus Borgnakke, and Jason B. Martz. "A thermodynamic model for homogeneous charge compression ignition combustion with recompression valve events and direct injection: Part I — Adiabatic core ignition model." International Journal of Engine Research 18, no. 7 (2016): 657–76. http://dx.doi.org/10.1177/1468087416664635.
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This two-part article presents a model for boosted and moderately stratified homogeneous charge compression ignition combustion for use in thermodynamic engine cycle simulations. The model consists of two components: one an ignition model for the prediction of auto-ignition onset and the other an empirical combustion rate model. This article focuses on the development and validation of the homogeneous charge compression ignition model for use under a broad range of operating conditions. Using computational fluid dynamics simulations of the negative valve overlap valve events typical of homogeneous charge compression ignition operation, it is shown that there is no noticeable reaction progress from low-temperature heat release, and that ignition is within the high-temperature regime ( T > 1000 K), starting within the highest temperature cells of the computational fluid dynamics domain. Additional parametric sweeps from the computational fluid dynamics simulations, including sweeps of speed, load, intake manifold pressures and temperature, dilution level and valve and direct injection timings, showed that the assumption of a homogeneous charge (equivalence ratio and residuals) is appropriate for ignition modelling under the conditions studied, considering the strong sensitivity of ignition timing to temperature and its weak compositional dependence. Use of the adiabatic core temperature predicted from the adiabatic core model resulted in temperatures within ±1% of the peak temperatures of the computational fluid dynamics domain near the time of ignition. Thus, the adiabatic core temperature can be used within an auto-ignition integral as a simple and effective method for estimating the onset of homogeneous charge compression ignition auto-ignition. The ignition model is then validated with an experimental 92.6 anti-knock index gasoline-fuelled homogeneous charge compression ignition dataset consisting of 290 data points covering a wide range of operating conditions. The tuned ignition model predictions of [Formula: see text] have a root mean square error of 1.7° crank angle and R2 = 0.63 compared to the experiments.
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Brahma, I., and J. N. Chi. "Development of a model-based transient calibration process for diesel engine electronic control module tables – Part 1: data requirements, processing, and analysis." International Journal of Engine Research 13, no. 1 (2011): 77–96. http://dx.doi.org/10.1177/1468087411424376.
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This is the first part of a study investigating a model-based transient calibration process for diesel engines. The motivation is to populate hundreds of parameters (which can be calibrated) in a methodical and optimum manner by using model-based optimization in conjunction with the manual process so that, relative to the manual process used by itself, a significant improvement in transient emissions and fuel consumption and a sizable reduction in calibration time and test cell requirements is achieved. Empirical transient modelling and optimization has been addressed in the second part of this work, while the required data for model training and generalization are the focus of the current work. Transient and steady-state data from a turbocharged multicylinder diesel engine have been examined from a model training perspective. A single-cylinder engine with external air-handling has been used to expand the steady-state data to encompass transient parameter space. Based on comparative model performance and differences in the non-parametric space, primarily driven by a high engine difference between exhaust and intake manifold pressures (Δ P) during transients, it has been recommended that transient emission models should be trained with transient training data. It has been shown that electronic control module (ECM) estimates of transient charge flow and the exhaust gas recirculation (EGR) fraction cannot be accurate at the high engine Δ P frequently encountered during transient operation, and that such estimates do not account for cylinder-to-cylinder variation. The effects of high engine Δ P must therefore be incorporated empirically by using transient data generated from a spectrum of transient calibrations. Specific recommendations on how to choose such calibrations, how many data to acquire, and how to specify transient segments for data acquisition have been made. Methods to process transient data to account for transport delays and sensor lags have been developed. The processed data have then been visualized using statistical means to understand transient emission formation. Two modes of transient opacity formation have been observed and described. The first mode is driven by high engine Δ P and low fresh air flowrates, while the second mode is driven by high engine Δ P and high EGR flowrates. The EGR fraction is inaccurately estimated at both modes, while EGR distribution has been shown to be present but unaccounted for by the ECM. The two modes and associated phenomena are essential to understanding why transient emission models are calibration dependent and furthermore how to choose training data that will result in good model generalization.
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Franchek, Matthew, Behrouz Ebrahimi, Karolos Grigoriadis, and Imad Makki. "Physics-Based Lumped-Parameter Modeling of Automotive Canister Fuel Purge." Journal of Dynamic Systems, Measurement, and Control 138, no. 7 (2016). http://dx.doi.org/10.1115/1.4033486.
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A physics-based model is presented to estimate the flow rate out of the fuel canister purged into the intake manifold. The lumped parameters of the model, including canister capacitance and flow resistance, are employed to obtain a first-order multi-input and single-output dynamic model. The vacuum pressure in the intake manifold and the fuel tank pressure serve as inputs, and the purged fuel flow rate is considered as the model output. The model does not require cumbersome computation, thereby allowing direct implementation in the fueling control to compensate for the extra fuel in regulation of the stoichiometric air–fuel ratio.
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Setiyo, M., S. Munahar, A. Triwiyatno, and J. D. Setiawan. "Modeling of Deceleration Fuel Cut-off for LPG Fuelled Engine using Fuzzy Logic Controller." International Journal of Vehicle Structures and Systems 9, no. 4 (2017). http://dx.doi.org/10.4273/ijvss.9.4.12.
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At the time of deceleration, continuous LPG flow in LPG fuelled engine causing over fuel consumption and increasing exhaust emissions, while the engine does not need fuel. Therefore, this paper presents a simulation of deceleration fuel cut-off (DFCO) system. Given that the fuel system control is complex and non-linear, modeling with fuzzy logic controller (FLC) has been selected because of simple, easy to understand and tolerant to improper data. The engine modeling is divided into several sections, including intake manifold dynamics and engine dynamics. The input values were processed by the membership function. A series of simulation results indicate that DFCO can be applied. The combination of throttle valve position, engine speed and manifold pressure is able to cut LPG flow at deceleration. As a conclusion, DFCO system is promising to be applied on LPG-fuelled vehicles for saving fuel and reducing emissions.
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Wang, Haoping, Yang Tian, Jérôme Bosche, and Ahmed El Hajjaji. "Modeling and Dynamical Feedback Control of a Vehicle Diesel Engine Speed and Air-Path." Journal of Dynamic Systems, Measurement, and Control 136, no. 6 (2014). http://dx.doi.org/10.1115/1.4027502.
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This paper presents a modeling and dynamical feedback stabilization control of a diesel engine which is equipped with a variable geometry turbocharger (VGT) and exhaust gas recirculation (EGR) valve. A fourth-order dimensional nonlinear model which takes into account the engine crankshaft speed dynamics and the air-path dynamics is proposed for the considered diesel engine. The difficulties for the control design are that the referred system is nonlinear, nonminimum phase unstable and coupled system. The fuel flow rate Wf which is considered as input for the engine crankshaft subsystem and acts as an external perturbation for the three-order dimensional nonminimum phase air-path subsystem. The global control objectives are to track desired values of engine speed, intake manifold pressure and compressor flow mass rate which can be suitably chosen according to low emission criterions. For the considered objectives, a dynamical feedback stabilization control with a two-loop structure of inner outer loop is proposed. The inner loop considers a control based on a Lyapunov function which realizes the desired engine speed trajectory tracking. The outer loop which is developed from a particular extended nonlinear air-path subsystem with its modified outputs concerns the coordinated EGR and VGT control and ensures both the desired intake manifold pressure and the desired compressor mass flow rate trajectory tracking. Meanwhile, this outer loop dynamical feedback stabilization control provides also the external fuel mass flow rate perturbation rejection. From the corresponding numerical simulation results, the proposed method efficiency is validated.
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Guo, Hongsheng, W. Stuart Neill, Wally Chippior, Hailin Li, and Joshua D. Taylor. "An Experimental and Modeling Study of HCCI Combustion Using n-Heptane." Journal of Engineering for Gas Turbines and Power 132, no. 2 (2009). http://dx.doi.org/10.1115/1.3124667.
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Homogeneous charge compression ignition (HCCI) is an advanced low-temperature combustion technology being considered for internal combustion engines due to its potential for high fuel conversion efficiency and extremely low emissions of particulate matter and oxides of nitrogen (NOx). In its simplest form, HCCI combustion involves the auto-ignition of a homogeneous mixture of fuel, air, and diluents at low to moderate temperatures and high pressure. Previous research has indicated that fuel chemistry has a strong impact on HCCI combustion. This paper reports the preliminary results of an experimental and modeling study of HCCI combustion using n-heptane, a volatile hydrocarbon with well known fuel chemistry. A Co-operative Fuel Research (CFR) engine was modified by the addition of a port fuel injection system to produce a homogeneous fuel-air mixture in the intake manifold, which contributed to a stable and repeatable HCCI combustion process. Detailed experiments were performed to explore the effects of critical engine parameters such as intake temperature, compression ratio, air/fuel ratio, engine speed, turbocharging, and intake mixture throttling on HCCI combustion. The influence of these parameters on the phasing of the low-temperature reaction, main combustion stage, and negative temperature coefficient delay period are presented and discussed. A single-zone numerical simulation with detailed fuel chemistry was developed and validated. The simulations show good agreement with the experimental data and capture important combustion phase trends as engine parameters are varied.
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Nadeer, E. P., Amit Patra, and Siddhartha Mukhopadhyay. "Hybrid State Space Modeling of a Spark Ignition Engine for Online Fault Diagnosis." Journal of Dynamic Systems, Measurement, and Control 140, no. 4 (2017). http://dx.doi.org/10.1115/1.4038164.
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In this work, a nonlinear hybrid state space model of a complete spark ignition (SI) gasoline engine system from throttle to muffler is developed using the mass and energy balance equations. It provides within-cycle dynamics of all the engine variables such as temperature, pressure, and mass of individual gas species in the intake manifold (IM), cylinder, and exhaust manifold (EM). The inputs to the model are the same as that commonly exercised by the engine control unit (ECU), and its outputs correspond to available engine sensors. It uses generally known engine parameters, does not require extensive engine maps found in mean value models (MVMs), and requires minimal experimentation for tuning. It is demonstrated that the model is able to capture a variety of engine faults by suitable parameterization. The state space modeling is parsimonious in having the minimum number of integrators in the model by appropriate choice of state. It leads to great computational efficiency due to the possibility of deriving the Jacobian expressions analytically in applications such as on-board state estimation. The model was validated both with data from an industry standard engine simulation and those from an actual engine after relevant modifications. For the test engine, the engine speed and crank angle were extracted from the crank position sensor signal. The model was seen to match the true values of engine variables both in simulation and experiments.
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"Numerical Analysis of Diesel Engine with Modified Inlet Valve." International Journal of Engineering and Advanced Technology 8, no. 6 (2019): 2378–80. http://dx.doi.org/10.35940/ijeat.f8220.088619.
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The Internal combustion engine is one of the widely used mechanical system. The primary aspect of all types of engines is the amount of power produced which, is affected by the complete combustion of a mixture of air and fuel. The objective of this present work is to outline the improved performance of single-cylinder Compression Ignition engine with the aid of geometrical modifications of Inlet manifold. The Study is performed on Kirlosakr CI engine. For modeling of engine assembly, CATIA V5 Software has been used. The Numerical simulations are performed with Ansys 14.5 and solver used as CFX. In this work, two different engine models such as Conventional valve and Modified valve with plate is being considered for CFD analysis. The simulation study of air flow motion with a valve lift of 4 mm, 6 mm and 8 mm is performed for both valve configurations. This numerical analysis aims to maximize the air velocity in the inlet valve with minimum turbulence which in turn improves the engine performance. The study is performed on the single cylinder four-stroke variable compression ratio diesel engines. In the present study, the air flow motion inside the intake manifold of an engine is simulated and investigations are performed by considering the six conditions of the intake valve. The results obtained acts as a basis for further investigation of a variety of valve geometry.
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"Numerical Study of Intake Flow Optimization using Genetic Algorithm and Artificial Neural Networks." International Journal of Mathematical Models and Methods in Applied Sciences 14 (April 30, 2020). http://dx.doi.org/10.46300/9101.2020.14.4.
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An easy way to comply with the conference paper formatting requirements is to use this document as a template and simply type your text into it. The increase in the performance of internal combustion engines for diesel engines has driven to follow alternative ways in order to improve the flow characteristics. This paper presents the computational fluid dynamics (CFD) modeling to study the effect of intake flow condition on the swirl ratio and volumetirc efficiency of a direct injection (DI) diesel engine. A single cylinder direct injection diesel engine with two directed intake ports whose outlet is tangential to the wall of the cylinder has been considered. The numerical results from this geometry are validated with the experimental results and published in the literature. In order to enhance the swirl ratio, intake flow in different components are adjusted instead of modifying the intake manifold shape and profile. The experiments are designed by full factorial approach for 3 variables (three components of intake velocity) to study the turbulent flows in a computational way and accomplished using OpenFOAM software. The induced swirl and tumble at the end of compression stroke are also computed and visualized. Numerous computations have been performed in this work during maximum intake valve lift and closed exhaust valve positions. To estimate the reliable data for predicted results, machine learning techniques such as artificial neural network is employed. Information is gathered for different combinations of intake velocity on swirl ratio and volumetric efficiency. Genetic algorithm is applied to fund the fittest data-set for several generations thereby the best optimal flow components are determined. The results from design of experiments approach and neural network techniques are compared.
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Mohr, Stephan, Henry Clarke, Colin P. Garner, Neville Rebelo, Andrew M. Williams, and Huayong Zhao. "On the Measurement and Modeling of High-Pressure Flows in Poppet Valves Under Steady-State and Transient Conditions." Journal of Fluids Engineering 139, no. 7 (2017). http://dx.doi.org/10.1115/1.4036150.
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Flow coefficients of intake valves and port combinations were determined experimentally for a compressed nitrogen engine under steady-state and dynamic flow conditions for inlet pressures up to 3.2 MPa. Variable valve timing was combined with an indexed parked piston cylinder unit for testing valve flows at different cylinder volumes while maintaining realistic in-cylinder transient pressure profiles by simply using a fixed area outlet orifice. A one-dimensional modeling approach describing three-dimensional valve flow characteristics has been developed by the use of variable flow coefficients that take into account the propagation of flow jets and their boundaries as a function of downstream/upstream pressure ratios. The results obtained for the dynamic flow cases were compared with steady-state results for the cylinder to inlet port pressure ratios ranges from 0.18 to 0.83. The deviation of flow coefficients for both cases is discussed using pulsatile flow theory. The key findings include the followings: (1) for a given valve lift, the steady-state flow coefficients fall by up to 21% with increasing cylinder/manifold pressure ratios within the measured range given above and (2) transient flow coefficients deviated from those measured for the steady-state flow as the valve lift increases beyond a critical value of approximately 0.5 mm. The deviation can be due to the insufficient time of the development of steady-state boundary layers, which can be quantified by the instantaneous Womersley number defined by using the transient hydraulic diameter. We show that it is possible to predict deviations of the transient valve flow from the steady-state measurements alone.
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Pulpeiro González, Jorge, King Ankobea-Ansah, Qian Peng, and Carrie M. Hall. "On the integration of physics-based and data-driven models for the prediction of gas exchange processes on a modern diesel engine." Proceedings of the Institution of Mechanical Engineers, Part D: Journal of Automobile Engineering, July 18, 2021, 095440702110314. http://dx.doi.org/10.1177/09544070211031401.
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The need for precise control of complex air handling systems on modern engines has driven research into model-based methods. While model-based control can provide improved performance over prior map-based methods, they require the creation of an accurate model. Physics-based models can be precise, but can also be computationally expensive and require extensive calibration. To address this limitation, this work explores the integration of data-driven models into an overall physics-based framework and applies this approach to the gas exchange processes of a diesel engine with a variable geometry turbocharger and exhaust gas recirculation. One of the most complex parts of this gas exchange loop is the turbocharger. Data-driven methods are used to capture the turbocharger performance and are also applied to the intake manifold, while the simpler features are captured with more traditional physics-based models. This combined modeling approach is able to capture the temperature and pressure dynamics with varying error levels depending on measurement availability and the inter-dependency of the submodels, with the turbocharger neural network model achieving a Normalized Mean Square Error (NMSE) of 5e-5 and the overall engine model achieving a NMSE of 4.5e-3. The work illustrates that the integration of data-driven models can improve overall model accuracy and may be able to reduce the number of sensors needed on the system. The contributions of this work are the development and demonstration of a neural network based turbocharger model and intake air path model, the development of empirical equation-based models for the rest of the engine components along the air path and the demonstration of the integration and interaction of these two types of model to adequately characterize engine operation for control applications.
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Galindo, José, Héctor Climent, Roberto Navarro, and Guillermo García-Olivas. "Assessment of the numerical and experimental methodology to predict EGR cylinder-to-cylinder dispersion and pollutant emissions." International Journal of Engine Research, December 2, 2020, 146808742097254. http://dx.doi.org/10.1177/1468087420972544.
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EGR cylinder-to-cylinder dispersion poses an important issue for piston engines, since it increases NOx and particulate matter (PM) emissions. In this work, the EGR distribution on a 6-cylinder intake manifold is analyzed by means of experiments, 0D/1D engine modeling and 3D CFD simulations at three different working points. Using a comprehensive set of measurements, statistical regressions for NOx and PM emissions are developed and employed to quantify the sensitivity of numerical configuration to EGR dispersion and subsequent increase of pollutants. CFD mesh and time-step size independence studies are conducted, taking into account their interrelation through the Courant number. The obtained numerical configuration is validated against experimental measurements, considering different unsteady RANS turbulence submodels ([Formula: see text] and [Formula: see text]) as well as the inviscid case. The agreement of the different approaches is quite sensitive to the operating conditions, obtaining root mean square errors for the average cylinder-to-cylinder EGR distribution between 1% and 17% and for the transient [Formula: see text] traces between 8% and 29%. However, for the worst-case scenario, the error in NOx and PM emissions prediction is below 2%. The regressions are employed to find a greater EGR distribution impact on pollutants when EGR rate or dispersion are increased. Flow investigation reveals the underlying reasons for the discrepancies and similarities between the predictions of the different turbulence submodels. A statistical analysis shows the significant errors that average [Formula: see text] probes make when assessing EGR cylinder-to-cylinder distribution, which is explain by the flow heterogeneity at some operating conditions.
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Millet, Jean-Baptiste, Fadila Maroteaux, and Fabrice Aubertin. "Air System and Diesel Combustion Modeling for Hardware in the Loop Applications." Journal of Engineering for Gas Turbines and Power 134, no. 4 (2012). http://dx.doi.org/10.1115/1.4004597.
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The development of engine control unit (ECU) systems for series production requires an important validation phase. In order to reduce the number of time consuming and expensive vehicle tests, the ECU is validated using hardware in the loop (HIL) test bench. The HIL simulates the engine behavior in real-time simulations to generate consistent sensor values for all engine operating points, e.g., starting phase, transient behavior, static behavior, etc. Mean value engine models (MVEM) are able to run in real time and are appropriate for HIL test systems. In this paper we present a full MVEM taking into account all engine components: air system (air filter, turbocharger, charge air cooler, throttle valve, intake and exhaust manifolds, EGR valve, and turbine), oxidation catalyst (OxiCat), and diesel particulate filter (DPF). Additionally, combustion models have been developed to simulate the influence of the injection strategies (pre, main, post, and late injections) on the exhaust temperature and the unburned hydrocarbon emission (HC). These are taken into consideration in the exothermal reactions models inside OxiCat and DPF. The results show that the model prediction in term of pressure and temperature are in good agreement with the original equipment manufacturer (OEM) project data. The after treatment temperature evolutions in the OxiCat and DPF are well reproduced by the proposed model.
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Kaleli, Alirıza, and Halil İbrahim Akolaş. "The design and development of a diesel engine electromechanical EGR cooling system based on machine learning-genetic algorithm prediction models to reduce emission and fuel consumption." Proceedings of the Institution of Mechanical Engineers, Part C: Journal of Mechanical Engineering Science, June 3, 2021, 095440622110200. http://dx.doi.org/10.1177/09544062211020045.
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Data-driven modelling techniques have recently been used in the development of engine design and control systems for defining the engine in-cylinder complex combustion process. The aim of this investigation is to improve exhaust emissions and fuel consumption by designing an electromechanical exhaust gas recirculation (EGR) cooling system consisting of an electric water pump and fan unlike conventional systems. To determine the effects of the EGR ratio and the temperature of the exhaust gas entering the intake manifold on the diesel engine parameters of nitrogen oxides (NOx) emission and brake specific fuel consumption (BSFC), four learning (ML) algorithms were adapted according to statistical evaluation criteria such as root mean squared error (RMSE), coefficient of determination (R2), mean squared error (MSE) and mean absolute error (MAE). The hyper parameters of the selected best model among four learning algorithms were determined by using grid search method. The results showed that the Gaussian process regression model (GPR) outperformed other ML models according to success error prediction of NOx and BSFC. Then, performance of the designed electromechanical EGR cooling system was analyzed under global driving conditions, the New European driving cycle (NEDC), and the world-wide harmonized light duty test procedure (WLTP). In these test cycles, global optimization was utilized with the GPR model as the objective function based on minimizing NOx and BSFC. Consequently, this study demonstrates the potential of the proposed system based on ML-GA to reduce NOx and BSFC by achieving reductions of 13.7%(NEDC)–9.98%(WLTP) and 2.61%(NEDC)–2.07%(WLTP) in NEDC and WLTP conditions, respectively compared to the conventional EGR cooling approach.