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2017-03-28
Technical Paper
2017-01-0852
Sathya prasad Potham, Le Zhao, Seong-Young Lee
This paper aims to present the results of numerical modeling and simulation of evaporation of single and multiple spherical n-heptane droplets impinging on a hot wall at a temperature above the Leidenfrost temperature at atmospheric pressure. Volume of Fluid (VOF) method is chosen for tracking the liquid gas interface and an open source CFD software, OpenFOAM, is chosen for modeling and simulations. The capability of VOF method implemented in interDyMFoam solver of OpenFOAM to simulate hydrodynamics during droplet-droplet interaction and droplet-film interaction is explored. The in-built solver is used to simulate problems in isothermal conditions and the simulation results are compared qualitatively with the published results to validate the solver. A numerical method for modeling heat and mass transfer during evaporation is implemented in conjunction with the VOF.
2017-03-28
Technical Paper
2017-01-1252
Ming Cheng, Lei Feng, Bo Chen
This paper studies the nonlinear model predictive control for a power-split Hybrid Electric Vehicle (HEV) power management system to improve the fuel economy. In this paper, a physics-based battery model is built and integrated with a base HEV model of Autonomie®, a powertrain and vehicle model architecture and development software from Argonne National Laboratory. The original equivalent circuit battery model has been replaced by a single particle electrochemical lithium ion battery model with battery thermal aging features. A predictive model that predicts the driver’s power request, the battery state of charge (SOC) and the engine fuel consumption is studied and used for the nonlinear model predictive controller (NMPC). A dedicated NMPC algorithm and its solver are developed and validated with the integrated HEV model. The performance of the NMPC algorithm is compared with that of a rule-based controller.
2017-03-28
Technical Paper
2017-01-0527
Arya Yazdani, Jeffrey Naber, Mahdi Shahbakhti, Paul Dice, Chris Glugla, Stephen Cooper, Douglas McEwan, Garlan Huberts
An accurate estimation of cycle-by-cycle in-cylinder mass and the composition of the cylinder charge is required for spark-ignition engine transient control strategies to obtain required torque, Air-Fuel-Ratio (AFR) and meet engine pollution regulations. Mass Air Flow (MAF) and Manifold Absolute Pressure (MAP) sensors have been utilized in different control strategies to achieve these targets; however, these sensors have response delay in transients. As an alternative to air flow metering, in-cylinder pressure sensors can be utilized to directly measure cylinder pressure, based on which, the amount of air charge can be estimated without the requirement to model the dynamics of the manifold.
2017-03-28
Technical Paper
2017-01-0553
Lorenzo Sforza, Tommaso Lucchini, Angelo Onorati, Xiucheng Zhu, Seong-Young Lee
Objective of this work is the incorporation of the flame stretch effects in an Eulerian-Lagrangian model for premixed SI combustion in order to describe ignition and flame propagation under highly inhomogeneous flow conditions. To this end, effects of energy transfer from electrical circuit and turbulent flame propagation were fully decoupled. The first ones are taken into account by Lagrangian particles whose main purpose is to generate an initial burned field in the computational domain. Turbulent flame development is instead considered only in the Eulerian gas phase for a better description of the local flow effects. To improve the model predictive capabilities, flame stretch effects were introduced in the turbulent combustion model by using formulations coming from the asymptotic theory and recently verified by means of DNS studies. Experiments carried out at Michigan Tech University in a pressurized, constant-volume vessel were used to validate the proposed approach.
2017-03-28
Technical Paper
2017-01-0672
Yanyu Wang, Jiongxun Zhang, Paul Dice, Xin Wang, Mahdi Shahbakhti, Jeffrey Naber, Michael Czekala, Qiuping Qu, Garlan Huberts
The effect of flow direction towards the spark plug electrodes on ignition parameters specifically… is analyzed using an innovative spark aerodynamics fixture that enables adjustment of the spark plug gap orientation and plug axis tilt angle with respect to the incoming flow. The ignition was supplied by a long discharge high energy coil (110mJ). The flow was supplied by compressed air and the spark was discharged into the ambient flow. The secondary ignition voltage and current were measured using a high speed (10MHz) NI PXI system, and the ignition-related metrics were calculated accordingly. Five different electrode designs were tested. These designs feature different positions of the electrode gap with respect to the flow and different shapes of the ground electrodes.
2017-03-28
Technical Paper
2017-01-0680
Yanyu Wang, Jiongxun Zhang, Xin Wang, Paul Dice, Mahdi Shahbakhti, Jeffrey Naber, Michael Czekala, Qiuping Qu, Garlan Huberts
The influence of spark plug orientation on early flame kernel development is investigated in an optically accessible gasoline direct injection homogeneous charged spark ignition engine. This investigation provides visual understanding and statistical characterization of spark plug orientation impacts the early flame kernel and thus combustion phasing and engine performance. The projected images of flame kernel were captured through natural flame chemiluminescence with a high-speed camera at 10,000 frames per second; and the ignition secondary discharge voltage and current were measured with a 10 MHz system. The combustion metrics were determined with a piezo-electric in-cylinder pressure transducer and real-time engine combustion analyzer. Three spark plug orientations with two different electrode designs were studied. The captured images of the flame were processed to … ensemble average and 2-D probability distribution and 1-D probability distribution.
2017-03-28
Technical Paper
2017-01-1251
Bin Zhou, Jeffrey Burl, Amir Rezaei
This paper introduced Equivalent Consumption Minimization Strategy (ECMS), and presents simulation results on how the ECMS penalty factor effects Lithium ion battery aging based on Matlab simulations. The vehicles simulated are the Honda Civic Hybrid and the Michigan Technological University developed Plug-in Hybrid Electric Vehicle (MTU-HEV). The battery data was used from A123 systems 20Ah Prismatic Pouch Cell for MTU-HEV, and A123 systems ANR26650 for Honda Civic Hybrid. Both vehicles are simulated using multiple combinations of highway and city drive cycles. For each combination of drive cycles, six ECMS penalty factor values are used. Battery aging is evaluated using the semiempirical model combined with accumulated Ah-throughput method which uses, as an input, the battery state of charge trajectory from the vehicle simulations. The tradeoff between fuel cost and battery aging cost is explicitly displayed.
2017-03-28
Technical Paper
2017-01-0001
Ming Cheng, Bo Chen
This paper studies the hardware-in-the-loop (HiL) design of a power-split hybrid electric vehicle (HEV) for the research of HEV lithium-ion battery aging. In this paper, an electrochemical model of a lithium ion battery pack with the characteristics of battery aging, is built and integrated into the vehicle model of Autonomie® software from Argonne National Laboratory. The vehicle model, together with the electrochemical battery model, is designed to run in a dSPACE real-time simulator while the powertrain power is managed by a dSPACE MicroAutoBoxII hardware controller. The control interface is designed using dSPACE ControlDesk to monitor the real-time simulation results. The HiL simulation results with the performance of vehicle fuel economy and dynamics, the thermal aging of the battery are presented and analyzed.
2017-03-28
Technical Paper
2017-01-0767
Jayant Kumar Arora, Mahdi Shahbakhti
Real-time control of Reactivity Controlled Compression Ignition (RCCI) during engine load and speed transient operation is challenging, since RCCI combustion phasing depends on fuel reactivity gradients and nonlinear thermo-kinetic reactions. This paper designs and implements a real-time closed-loop combustion controller to maintain an optimum combustion phasing during RCCI engine transient operation. New algorithms for real-time In-cylinder pressure analysis and combustion phasing calculations are developed and embedded on a Field Programmable Gate Array (FPGA) to compute RCCI combustion and performance metrics on cycle-by-cycle basis. This cycle-by-cycle data is then used as a feedback to the combustion controller, which is implemented on a real-time processor.
2017-03-28
Technical Paper
2017-01-1199
Khalid Khan, Bin Zhou, Amir Rezaei
A high voltage battery is an essential part of hybrid electric vehicles (HEVs). It is imperative to precisely estimate the state of charge (SOC) and state of health (SOH) of battery in real time to maintain reliable vehicle operating conditions. This paper presents a method of estimating SOC and SOH through the incorporation of current integration, voltage translation, and Ah-throughput. SOC estimation utilizing current integration is inadequate due to the accumulation of errors over the period of usage. Thus voltage translation of SOC is applied to rectify current integration method which improves the accuracy of estimation. Voltage translation data is obtained by subjecting the battery to hybrid pulse power characterization (HPPC) test. The Battery State of Health was determined by semi-empirical model combined with accumulated Ah-throughput method. Battery state of charge was employed as an input to estimate damages accumulated to battery aging through a real-time model.
2016-10-17
Technical Paper
2016-01-2309
Ehsan Ansari, Kamran Poorghasemi, Behrouz Khoshbakht Irdmousa, Mahdi Shahbakhti, Jeffrey Naber
Abstract Reactivity Controlled Compression Ignition (RCCI) is a promising dual-fuel Low Temperature Combustion (LTC) mode with significant potential for reducing NOx and particulate emissions while improving or maintaining thermal efficiency compared to Conventional Diesel Combustion (CDC) engines. The large reactivity difference between diesel and Natural Gas (NG) fuels provides a strong control variable for phasing and shaping combustion heat release. In this work, the Brake Thermal Efficiencies (BTE), emissions and combustion characteristics of a light duty 1.9L, four-cylinder diesel engine operating in single fuel diesel mode and in Diesel-NG RCCI mode are investigated and compared. The engine was operated at speeds of 1300 to 2500 RPM and loads of 1 to 7 bar BMEP. Operation was limited to 10 bar/deg Maximum Pressure Rise Rate (MPRR) and 6% Coefficient of Variation (COV) of IMEP.
2016-10-17
Technical Paper
2016-01-2361
Ali Solouk, Mohammad Shakiba-herfeh, Kaushik Kannan, Hamit Solmaz, Paul Dice, Mehran Bidarvatan, Naga Nithin Teja Kondipati, Mahdi Shahbakhti
Low Temperature Combustion (LTC) engines are promising to improve powertrain fuel economy and reduce NOx and soot emissions by improving the in-cylinder combustion process. However, the narrow operating range of LTC engines limits the use of these engines in conventional powertrains. Extended range electric vehicles (EREVs), by decoupling the engine from the drivetrain, allows the engine to operate in a limited operating range; thus, EREVs offer an ideal platform for realizing the advantages of LTC engines. In this study, the global optimum fuel economy improvement of an experimentally developed 2-liter multi-mode LTC engine in a series EREV is investigated. The engine operation modes include Homogeneous-Charge Compression Ignition (HCCI), Reactivity Controlled Compression Ignition (RCCI), and conventional Spark Ignition (SI).
2016-10-17
Journal Article
2016-01-2364
James Sevik, Michael Pamminger, Thomas Wallner, Riccardo Scarcelli, Brad Boyer, Steven Wooldridge, Carrie Hall, Scott Miers
Interest in natural gas as an alternative fuel source to petroleum fuels for light-duty vehicle applications has increased due to its domestic availability and stable price compared to gasoline. With its higher hydrogen-to-carbon ratio, natural gas has the potential to reduce engine out carbon dioxide emissions, which has shown to be a strong greenhouse gas contributor. For part-load conditions, the lower flame speeds of natural gas can lead to an increased duration in the inflammation process with traditional port-injection. Direct-injection of natural gas can increase in-cylinder turbulence and has the potential to reduce problems typically associated with port-injection of natural gas, such as lower flame speeds and poor dilution tolerance. A study was designed and executed to investigate the effects of direct-injection of natural gas at part-load conditions.
2016-09-27
Technical Paper
2016-01-8082
Kaushik Saha, Ahmed Abdul Moiz, Anita Ramirez, Sibendu Som, Munidhar Biruduganti, Michael Bima, Patrick Powell
Abstract The medium and heavy duty vehicle industry has fostered an increase in emissions research with the aim of reducing NOx while maintaining power output and thermal efficiency. This research describes a proof-of-concept numerical study conducted on a Caterpillar single-cylinder research engine. The target of the study is to reduce NOx by taking a unique approach to combustion air handling and utilizing enriched nitrogen and oxygen gas streams provided by Air Separation Membranes. A large set of test cases were initially carried out for closed-cycle situations to determine an appropriate set of operating conditions that are conducive for NOx reduction and gas diffusion properties. Several parameters - experimental and numerical, were considered. Experimental aspects, such as engine RPM, fuel injection pressure, start of injection, spray inclusion angle, and valve timings were considered for the parametric study.
2016-04-05
Journal Article
2016-01-0159
Luting Wang, Chong Cao, Bo Chen
Abstract This paper studies the bi-directional power flow control between Plug-in Electric Vehicles (PEVs) and an electrical grid. A grid-tied charging system that enables both Grid-to-Vehicle (G2V) and Vehicle-to-Grid (V2G) charging/discharging is modeled using SimPowerSystems in Matlab/Simulink environment. A bi-directional AC-DC converter and a bi-directional DC-DC buck-boost converter are integrated to charge and discharge PEV batteries. For AC-DC converter control, Predictive Current Control (PCC) strategy is employed to enable grid current to reach a reference current after one modulation period. In addition, Phase Lock Loop (PLL) and a band-stop filter are designed to lock the grid voltage phase and reduce harmonics. Bi-directional power flow is realized by controlling the mode of the DC-DC converter. Simulation tests are conducted to evaluate the performance of this bi-directional charging system.
2015-04-14
Technical Paper
2015-01-0965
James M. Sevik, Thomas Wallner, Scott Miers, Jeff Wasil
Abstract In 1990, Roy Douglas developed an analytical method to calculate the global air-to-fuel ratio of a two-stroke engine from exhaust gas emissions. While this method has considerable application to two-stroke engines, it does not permit the calculation of air-to-fuel ratios for oxygenated fuels. This study proposed modifications to the Roy Douglas method such that it can be applied to oxygenated fuels. The ISO #16183 standard, the modified Spindt method, and the Brettschneider method were used to evaluate the modifications to the Roy Douglas method. In addition, a trapped air-to-fuel ratio, appropriate for two-stroke engines, was also modified to incorporate oxygenated fuels. To validate the modified calculation method, tests were performed using a two-stroke carbureted and two-stroke direct injected marine outboard engine over a five-mode marine test cycle running indolene and low level blends of ethanol and iso-butanol fuels.
2015-04-14
Technical Paper
2015-01-1059
Harsha Shankar Surenahalli, Gordon Parker, John H. Johnson
Abstract Diesel Oxidation Catalysts (DOC) are used on heavy duty diesel engine applications and experience large internal temperature variations from 150 to 600°C. The DOC oxidizes the CO and HC in the exhaust to CO2 and H2O and oxidizes NO to NO2. The oxidation reactions are functions of its internal temperatures. Hence, accurate estimation of internal temperatures is important both for onboard diagnostic and aftertreatment closed loop control strategies. This paper focuses on the development of a reduced order model and an Extended Kalman Filter (EKF) state estimator for a DOC. The reduced order model simulation results are compared to experimental data. This is important since the reduced order model is used in the EKF estimator to predict the CO, NO, NO2 and HC concentrations in the DOC and at the outlet. The estimator was exercised using transient drive cycle engine data. The closed loop EKF improves the temperature estimate inside the DOC compared to the open loop estimator.
2015-04-14
Technical Paper
2015-01-0948
Le (Emma) Zhao, Ahmed Abdul Moiz, Jeffrey Naber, Seong-Young Lee, Sam Barros, William Atkinson
Abstract High-speed spray-to-spray liquid impingement could be an effective phenomenon for the spray propagation and droplet vaporization. To achieve higher vaporization efficiency, impingement from two-hole nozzles is analyzed in this paper. This paper focuses on investigating vaporization mechanism as a function of the impingement location and the collision breakup process provided by two-hole impinging jet nozzles. CFD (Computational Fluid Dynamics) is adopted to do simulation. Lagrangian model is used to predict jet-to-jet impingement and droplet breakup conditions while KH-RT breakup and O'Rourke collision models are implemented for the simulation. The paper includes three parts: First, a single spray injected into an initially quiescent constant volume chamber using the Lagrangian approach is simulated to identify the breakup region, which will be considered as a reference to study two-hole impinging jet nozzles.
2015-04-14
Technical Paper
2015-01-1044
Kiran C. Premchand, Krishnan Raghavan, John H. Johnson
Abstract Numerical models of aftertreatment devices are increasingly becoming indispensable tools in the development of aftertreatment systems that enable modern diesel engines to comply with exhaust emissions regulations while minimizing the cost and development time involved. Such a numerical model was developed at Michigan Technological University (MTU) [1] and demonstrated to be able to simulate the experimental data [2] in predicting the characteristic pressure drop and PM mass retained during passive oxidation [3] and active regeneration [4] of a catalyzed diesel particulate filter (CPF) on a Cummins ISL engine. One of the critical aspects of a calibrated numerical model is its usability - in other words, how useful is the model in predicting the pressure drop and the PM mass retained in another particulate filter on a different engine without the need for extensive recalibration.
2015-04-14
Technical Paper
2015-01-1748
Hrishikesh A. Saigaonkar, Mohammadreza Nazemi, Mahdi Shahbakhti
Abstract In this study, the effects of Variable Valve Timing (VVT) on the performance of a Homogeneous Charge Compression Ignition (HCCI) engine are analyzed by developing a computationally efficient modeling approach for the HCCI engine cycle. A full engine cycle model called Sequential Model for Residual affected HCCI (SMRH) is developed using a multi zone thermo-kinetic combustion model coupled with flow dynamic models. The SMRH utilizes CHEMKIN®-PRO and GT-POWER® software along with an in-house exhaust gas flow model. Experimental data from a single cylinder HCCI engine is used to validate the model for different operating conditions. Validation results show a good agreement with experimental data for predicting combustion phasing, Indicated Mean Effective Pressure (IMEP), thermal efficiency as well as CO emission. The experimentally validated SMRH is then used to investigate the effects of intake and exhaust valve timing on residual affected HCCI engine combustion.
2013-04-08
Technical Paper
2013-01-0312
Vaibhav Kale, Yeliana Yeliana, Jeremy Worm, Jeffrey Naber
Estimating internal residual during engine operation is essential to robust control during startup, steady state, and transient operation. Internal residual has a significant effect on combustion flame propagation, combustion stability and emissions. Accurate residual estimate also provides a better foundation for optimizing open loop fuel control during startup, while providing a basis for reducing emissions during closed loop control. In this paper we develop an improved model to estimate residual gas fraction by means of isolation and characterization of the physical processes in the gas exchange. Examining existing residuals model as the base, we address their deficiencies making changes to appropriate terms to the model. Existing models do not work well under wide angle dual independent cam phasing. The improved residual estimation model is not limited by the initial data set used for its calibration and does not need cylinder pressure data.
2013-04-08
Technical Paper
2013-01-1573
Andrew Stevens, Yannan Sun, Jianming Lian, Maruthi Devarakonda, Gordon Parker
In this paper, we develop a method for optimizing urea dosing to minimize the downstream readings from a production NO x sensor that has cross-sensitivity to ammonia. This approach favors high NO x conversion and reduced ammonia slip. The motivation for this work is to define a process to identify the maximum selective catalytic reduction SCR performance bounds for a given drive cycle. The approach uses a model structure that has a closed-form optimal solution for the urea injection. Every aftertreatment system has its own, unique model, which must be identified and validated. To demonstrate the approach, a model is identified and validated using experimental SCR input/output NO x sensor data from a 2010 Cummins 6.7L ISB production engine. The optimal control law is then simulated and its performance compared against the simulated performance of the SCR using experimental data for its inlet conditions.
2013-04-08
Technical Paper
2013-01-1581
Harsha Shankar Surenahalli, Gordon Parker, John H. Johnson
This paper focuses on the development of an Extended Kalman Filter for estimating internal species concentration and storage states of an SCR using NOX and NH₃ sensors. The motivation for this work was twofold. First, knowledge of internal states may be useful for onboard diagnostic strategy development. In particular, significant errors between the outlet NOX or NH₃ sensors, reconstructed from estimated states, and the measured NOX or NH₃ concentrations may aid OBD strategies that attempt to identify particular system failure modes. Second, the EKF described estimates not only stored ammonia but also NO, NO₂ and NH₃ gas concentrations within and exiting the SCR. Exploiting knowledge of the individual species concentrations, instead of lumping them together as NOX, can yield improved closed loop urea controller performance in terms of reduced urea consumption and better NOX conversion.
2013-04-08
Journal Article
2013-01-1594
Jaclyn Johnson, Hai-Wen Ge, Jeffrey Naber, Seong-Young Lee, Eric Kurtz, Nan Robarge
Diesel combustion and emissions formation is spray and mixing controlled and understanding spray parameters is key to determining the impact of fuel injector operation and nozzle design on combustion and emissions. In this study, both spray visualization and computational fluid dynamics (CFD) modeling were undertaken to investigate key mechanisms for liquid length fluctuations. For the experimental portion of this study a common rail piezoelectric injector was tested in an optically accessible constant volume combustion vessel. Liquid penetration of the spray was determined via processing of images acquired from Mie back scattering under vaporizing conditions by injecting into a charge gas at elevated temperature with a 0% oxygen environment. Tests were undertaken at a gas density of 34.8 kg/m₃, 2000 bar injection pressure, and at ambient temperatures of 900, 1100, and 1300 K.
2013-04-08
Technical Paper
2013-01-0319
Khanh Cung, Meghraj Bhagat, Anqi Zhang, Seong-Young Lee
Particular matter (PM) has been greatly concerned over the recent decades due to the constantly increasing restriction on its effect on environmental aspect. Oxygenated fuel such as dimethyl ether (DME) has been known to have beneficial impact on diesel engine emissions in terms of zero soot formation. In current study, under several ambient conditions including surrounding gas temperature and oxygen percentages, soot and emission formation of DME spray is investigated to provide a comparison with other diesel surrogate (n-heptane) and JP-8 surrogate fuels. One important work is to develop a number of chemical kinetic mechanisms with soot chemistry including the growth of polycyclic aromatic hydrocarbon (PAH) and nitro oxides (NOx) formation. Using the developing detailed mechanisms, several numerical approaches were introduced to provide an integrated picture of emission formations.
2013-04-08
Technical Paper
2013-01-0250
Meghraj Bhagat, Khanh Cung, Jaclyn Johnson, Seong-Young Lee, Jeffrey Naber, Sam Barros
Water spray characterization of a multi-hole injector under pressures and temperatures representative of engine-relevant conditions was investigated for naturally aspirated and boosted engine conditions. Experiments were conducted in an optically accessible pressure vessel using a high-speed Schlieren imaging to visualize the transient water spray. The experimental conditions included a range of injection pressures of 34, 68, and 102 bar and ambient temperatures of 30 - 200°C, which includes flash-boiling and non-flash-boiling conditions. Transient spray tip penetration and spray angle were characterized via image processing of raw Schlieren images using Matlab code. The CONVERGE CFD software was used to simulate the water spray obtained experimentally in the vessel. CFD parameters were tuned and validated against the experimental results of spray profile and spray tip penetration measured in the combustion vessel (CV).
2013-04-08
Journal Article
2013-01-1627
Anqi Zhang, Khanh Cung, Seong-Young Lee, Jeffrey Naber, Garlan Huberts, Michael Czekala, Qiuping Qu
An operational scheme with fuel-lean and exhaust gas dilution in spark-ignited engines increases thermal efficiency and decreases NOx emission, while these operations inherently induce combustion instability and thus large cycle-to-cycle variation in engine. In order to stabilize combustion variations, the development of an advanced ignition system is becoming critical. To quantify the impact of spark-ignition discharge, ignitability tests were conducted in an optically accessible combustion vessel to characterize the flame kernel development of lean methane-air mixture with CO₂ simulating exhaust diluent. A shrouded fan was used to generate turbulence in the vicinity of J-gap spark plug and a Variable Output Ignition System (VOIS) capable of producing a varied set of spark discharge patterns was developed and used as an ignition source.
2012-04-16
Technical Paper
2012-01-1073
Vaibhav Kale, Halim Santoso, Craig Marriott, Jeremy Worm, Jeffrey Naber
An experimental study and analysis was conducted to investigate cold start robustness of an ethanol flex-fuel spark ignition (SI) direct injection (DI) engine. Cold starting with ethanol fuel blends is a known challenge due to the fuel characteristics. The program was performed to investigate strategies to reduce the enrichment requirements for the first firing cycle during a cold start. In this study a single-cylinder SIDI research engine was used to investigate gasoline and E85 fuels which were tested with three piston configurations (CR11F, CR11B, CR15.5B - which includes changes in compression ratio and piston geometry), at three intake cam positions (95, 110, 125 °aTDC), and two fuel pressures (low: 0.4 MPa and high: 3.0 MPa) at 25°C±1°C engine and air temperature, for the first cycle of an engine start.
2012-04-16
Journal Article
2012-01-0742
Lei Feng, Wenjia Liu, Bo Chen
The vehicle driving cycles affect the performance of a hybrid vehicle control strategy, as a result, the overall performance of the vehicle, such as fuel consumption and emission. By identifying the driving cycles of a vehicle, the control system is able to dynamically change the control strategy (or parameters) to the best one to adapt to the changes of vehicle driving patterns. This paper studies the supervised driving cycle recognition using pattern recognition approach. With pattern recognition method, a driving cycle is represented by feature vectors that are formed by a set of parameters to which the driving cycle is sensitive. The on-line driving pattern recognition is achieved by calculating the feature vectors and classifying these feature vectors to one of the driving patterns in the reference database. To establish reference driving cycle database, the representative feature vectors for four federal driving cycles are generated using feature extraction method.
2011-05-17
Technical Paper
2011-01-1662
Chad Walber, Jason R. Blough, Mark Johnson, Carl Anderson
When testing dynamic structures, it is important to note that the dynamic system in question may be submerged into a fluid during operation and to properly test the structure under the same condition in order to understand the true dynamic parameters of the system. In this way, the mass and stiffness coupling to the particular fluid, for the case of this study, automatic transmission fluid, may be taken into account. This is especially important in light structures where the coupling between the fluid mass and the structural mass may be great. A structure was tested with a laser vibrometer using several impact methods in open air to determine which impact method would be most suitable for submerged testing. The structure was then submerged in transmission fluid with an accelerometer attached and subsequently tested and compared to the previous results.
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