The Experts below are selected from a list of 195 Experts worldwide ranked by ideXlab platform

Aamer Iqbal Bhatti - One of the best experts on this subject based on the ideXlab platform.

  • Second order sliding mode observer for estimation of SI Engine Volumetric Efficiency & Throttle Discharge Coefficient
    2010 11th International Workshop on Variable Structure Systems (VSS), 2010
    Co-Authors: Qadeer Ahmed, Aamer Iqbal Bhatti
    Abstract:

    Identification and estimation of non-measurable critical parameters of automotive Engine provide significant information to monitor its functions and health. This article proposes a novel estimation scheme of identifying such parameters. Two of the critical parameters are: Volumetric Efficiency and Throttle Discharge Coefficient. These parameters are estimated from the single nonlinear equation of Engine inlet manifold pressure dynamics. The estimation scheme utilizes second order sliding mode observer based on super twisting algorithm. Mean Value Engine Model is considered to model the inlet manifold behavior. The estimation is carried out on production vehicle equipped with Engine control unit compliant to OBD-II standards. The proposed observer is simple enough for implementation. The estimated parameters have vast application in the area of Engine controller design and fault diagnosis/prognosis.

  • second order sliding mode observer for estimation of si Engine Volumetric Efficiency throttle discharge coefficient
    International Workshop on Variable Structure Systems, 2010
    Co-Authors: Qadeer Ahmed, Aamer Iqbal Bhatti
    Abstract:

    Identification and estimation of non-measurable critical parameters of automotive Engine provide significant information to monitor its functions and health. This article proposes a novel estimation scheme of identifying such parameters. Two of the critical parameters are: Volumetric Efficiency and Throttle Discharge Coefficient. These parameters are estimated from the single nonlinear equation of Engine inlet manifold pressure dynamics. The estimation scheme utilizes second order sliding mode observer based on super twisting algorithm. Mean Value Engine Model is considered to model the inlet manifold behavior. The estimation is carried out on production vehicle equipped with Engine control unit compliant to OBD-II standards. The proposed observer is simple enough for implementation. The estimated parameters have vast application in the area of Engine controller design and fault diagnosis/prognosis.

Qadeer Ahmed - One of the best experts on this subject based on the ideXlab platform.

  • Second order sliding mode observer for estimation of SI Engine Volumetric Efficiency & Throttle Discharge Coefficient
    2010 11th International Workshop on Variable Structure Systems (VSS), 2010
    Co-Authors: Qadeer Ahmed, Aamer Iqbal Bhatti
    Abstract:

    Identification and estimation of non-measurable critical parameters of automotive Engine provide significant information to monitor its functions and health. This article proposes a novel estimation scheme of identifying such parameters. Two of the critical parameters are: Volumetric Efficiency and Throttle Discharge Coefficient. These parameters are estimated from the single nonlinear equation of Engine inlet manifold pressure dynamics. The estimation scheme utilizes second order sliding mode observer based on super twisting algorithm. Mean Value Engine Model is considered to model the inlet manifold behavior. The estimation is carried out on production vehicle equipped with Engine control unit compliant to OBD-II standards. The proposed observer is simple enough for implementation. The estimated parameters have vast application in the area of Engine controller design and fault diagnosis/prognosis.

  • second order sliding mode observer for estimation of si Engine Volumetric Efficiency throttle discharge coefficient
    International Workshop on Variable Structure Systems, 2010
    Co-Authors: Qadeer Ahmed, Aamer Iqbal Bhatti
    Abstract:

    Identification and estimation of non-measurable critical parameters of automotive Engine provide significant information to monitor its functions and health. This article proposes a novel estimation scheme of identifying such parameters. Two of the critical parameters are: Volumetric Efficiency and Throttle Discharge Coefficient. These parameters are estimated from the single nonlinear equation of Engine inlet manifold pressure dynamics. The estimation scheme utilizes second order sliding mode observer based on super twisting algorithm. Mean Value Engine Model is considered to model the inlet manifold behavior. The estimation is carried out on production vehicle equipped with Engine control unit compliant to OBD-II standards. The proposed observer is simple enough for implementation. The estimated parameters have vast application in the area of Engine controller design and fault diagnosis/prognosis.

Roberto Cipollone - One of the best experts on this subject based on the ideXlab platform.

  • Flow and thermal management of Engine intake air for fuel and emissions saving
    Energy Conversion and Management, 2018
    Co-Authors: Davide Di Battista, M. Di Bartolomeo, Roberto Cipollone
    Abstract:

    Abstract Charge air cooling is the typical technique to reduce temperature of the Engine intake air, increasing air density and improving cylinder filling and Engine Volumetric Efficiency in present turbocharged diesel Engines. Usually, charge air is cooled by environmental air that crosses a heat exchanger placed in front of the vehicle: its cooling capacity is related to the vehicle speed and other constraints (presence of the main radiator). This leads to an intake air temperature from 30 to 80 °C, depending on Engine load, external air conditions and vehicle speed again. If the intake air was more cooled down, the Engine Volumetric Efficiency would be further increased. This can only be done by the use of a dedicated cooling fluid, operating at lower temperature with respect to external air. In this paper, therefore, an evaporator, mounted in parallel with the one of the refrigeration unit used for cabin cooling, was placed on the intake line of a turbocharged diesel Engine (F1C IVECO Engine), tested on a high speed dynamometer bench: the air refrigeration unit is also composed by a compressor, a condenser and a thermostatic expansion valve. The effects of the undercooling of the charge air have been experimental assessed in terms of fuel consumption and regulated emission reduction, evaluated on the most common Engine operating points. Mechanical power demand of the compressor has obviously taken into account in order to assess overall benefits. Achieved net fuel consumption is in the order of 1% at fixed conditions operating the Engine as a light duty type, when the intake air sub-cooling is turned on. A benefit on the regulated emissions has been observed (Nitrogen Oxides, Soot) regardless of the setup of the Engine combustion processes (injection time, fuel distribution for each injection, Exhaust Gas Recirculated rate). Unburned hydrocarbon and Carbon monoxide behavior, on the other hand, deserves some more attention and call for the re-calibration of the previously cited combustion control parameters.

  • Experimental assessment of Engine charge air cooling by a refrigeration unit
    Energy Procedia, 2017
    Co-Authors: Roberto Cipollone, Davide Di Battista, Diego Vittorini
    Abstract:

    Abstract Following the increasing awareness on the global warming, international governments have set up severe targets on CO2 emission in transportation sector: the overcoming of these limits produces a fine which directly influences the market value of the vehicle. Moreover, concerning the traditional pollutants, they still remain targeted by future EURO6(b-c-d) limits. Charge air cooling, in turbocharged diesel Engines, is widely used to increase air density, improve cylinder filling and, definitively, Engine Volumetric Efficiency. This is usually done through a heat exchanger fed by environmental air positioned after the charge air compression: the cooling is strictly related to vehicle speed, dedicated radiator positioning, Engine operating point and environmental temperature. All these factors lead to an in-cylinder intake air temperature in the 40-70°C range. A refrigerating unit, featuring an evaporator, suitably placed inside the intake manifold, could provide an additional cooling. Such an option is not so difficult to be implemented considering that a conditioning unit is already present on board for cabin comfort. This unit often is over-designed and frequently under-employed. In this paper an evaporator was placed on the intake line of a turbocharged diesel Engine, available on a test bench, and the effects of the under-cooling of the charge air have been experimentally assessed. The evaporator is fed by an air refrigeration unit present on vehicle board for cabin conditioning. Fuel consumption saving has been observed as well as a sensible pollutants reduction, taking obviously into account the mechanical power required by the compressor.

S S Chung - One of the best experts on this subject based on the ideXlab platform.

  • An experimental study on spray and combustion characteristics of LPG for application in direct-injection
    Journal of Mechanical Science and Technology, 2016
    Co-Authors: S S Chung, Jeongkuk Yeom, Jeonghwan Yoon, Seongill Hwang
    Abstract:

    As an alternative fuel that can be used in SI Engines, LPG is a clean fuel with larger H/C ratio compared to gasoline, low CO_2 emission, and small amount of pollutants such as sulfur compounds. In the Spark-ignition (SI) Engine, Direct injection (DI) technology can significantly increase the Engine Volumetric Efficiency and decrease the need for a throttle valve. DI allows Engine operation with the stratified charge, which enables a relatively higher combustion Efficiency. Stratified charge can be supplied to nearby spark plugs to allow for overall lean combustion, which improves thermal Efficiency and can cope with problems regarding emission regulations. In this study, a visualization experiment system that consists of visualization combustion chamber, air supply control system, emission control system, LPG fuel supply system, electronic control system and image data acquisition system was designed and manufactured. For all cases for which ignition was successful, flame propagation image was digitally recorded using ICCD camera, and the recorded flame propagation characteristics were examined. This study, in its results, is expected to make a contribution in terms of important data for the design and optimization of a Spark-ignited direct injection (SIDI) LPG Engine.

  • experimental study on the spray and combustion characteristics of sidi cng
    International Journal of Automotive Technology, 2014
    Co-Authors: Y Liu, S I Hwang, Jeongkuk Yeom, S S Chung
    Abstract:

    Compressed natural gas (CNG) is regarded as one of the most promising alternative fuels. In the spark-ignition (SI) Engine, direct injection (DI) technology can significantly increase the Engine Volumetric Efficiency and reduce “pumping losses” in Engines without a throttle valve. DI allows Engine operation with the stratified charge which enables relatively higher combustion Efficiency. In this study, a combustion chamber with a visualization system is designed. The spray development and combustion propagation process of spark-ignition direct injection (SIDI) CNG were digital recorded and analyzed. The ignition probability was also examined. The results of this study can contribute important data for the design and optimization of the SIDI CNG Engine.

  • An experimental study on the effects of impingement-walls on the spray and combustion characteristics of SIDI CNG
    Journal of Mechanical Science and Technology, 2012
    Co-Authors: Y Liu, Jeongkuk Yeom, S S Chung
    Abstract:

    Compressed natural gas (CNG) is regarded as one of the most promising alternative fuels, and maybe the cleanest fuel for the sparkignition (SI) Engine. In the SI Engine, direct injection (DI) technology can significantly increase the Engine Volumetric Efficiency and decrease the need of throttle valve. During low load and speed conditions, DI allows Engine operation with the stratified charge, and the use of extremely lean fuel-air mixture enables relatively higher combustion Efficiency. In this study, a combustion chamber with a visualization system is designed. The spray development and combustion propagation processes SIDI CNG were digital recorded. It was found that high injection pressure reduced the ignition probability significantly because of quenching of flame kernel. To improve the ignition probability, three kinds of impingement-walls were designed to help the mixture preparation. It was found that the CNG-air mixture can be easily formed after spray-wall impingement and the ignition probability was also improved. The results of this study can contribute important data for the design and optimization of spark-ignition direct injection (SIDI) CNG Engine.

Yongsheng Chai - One of the best experts on this subject based on the ideXlab platform.

  • Finite-Time Identification Algorithm for Volumetric Efficiency Map in SI Gasoline Engines
    IEEE Transactions on Industrial Electronics, 2020
    Co-Authors: Changhui Wang, Mei Liang, Yongsheng Chai
    Abstract:

    In contrast to the calibration of an Engine Volumetric Efficiency map (or lookup tables) from steady-state data, a method for the identification of the Engine Volumetric Efficiency map using transient condition data is developed in this article, which can reduce the time and cost of Engine map calibration. To expediently identify the map parameters, the mathematical description of the Volumetric Efficiency for a spark ignition (SI) gasoline Engine is approximated in terms of a piecewise bilinear interpolation model with unknown map parameters, which can be rewritten as a dot product between a regression vector and a parameter vector using a membership function. With the combination of a map regression model and an SI gasoline Engine air path dynamic model, a finite-time adaptive observer is designed to estimate the constant map parameters, for which the parameter estimation error information is explicitly derived. To guarantee the convergence of the identification for all map parameters, a trajectory scheme of the transient condition data from the map input that passes through all of the interpolation regions is introduced. The performance of the proposed algorithm is validated against transient condition data generated by the Engine simulation software enDYNA provided by Tesis. It is shown that the Volumetric Efficiency map of an SI gasoline Engine simulated with enDYNA is approximated acceptably by the proposed method.