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2016-10-24
Event
Separate sub-sessions cover zero-dimensional, one-dimensional, and quasi-dimensional models for simulation of SI and CI engines with respect to: engine breathing, boosting, and acoustics; SI combustion and emissions; CI combustion and emissions; fundamentals of engine thermodynamics; numerical modeling of gas dynamics; thermal management; mechanical and lubrication systems; system level models for controls; system level models for vehicle fuel economy and emissions predictions.
2016-05-11 ...
  • May 11-12, 2016 (8:30 a.m. - 4:30 p.m.) - Tysons, Virginia
Training / Education Classroom Seminars
Engineers are taught to create designs that meet customer specifications. When creating these designs, the focus is usually on the nominal values rather than variation. Robustness refers to creating designs that are insensitive to variability in the inputs. Much of the literature on robustness is dedicated to experimental techniques, particularly Taguchi techniques, which advocate using experiments with replications to estimate variation. This course presents mathematical formulas based on derivatives to determine system variation based on input variation and knowledge of the engineering function.
2016-05-05
Journal Article
2015-01-9148
Saeed Asgari, Shailendra Kaushik
Abstract A linear parameter varying (LPV) reduced order model (ROM) is used to approximate the volume-averaged temperature of battery cells in one of the modules of the battery pack with varying mass flow rate of cooling fluid using uniform heat source as inputs. The ROM runs orders of magnitude faster than the original CFD model. To reduce the time it takes to generate training data, used in building LPV ROM, a divide-and-conquer approach is introduced. This is done by dividing the battery module into a series of mid-cell and end-cell units. A mid-cell unit is composed of a cooling channel sandwiched in between two half -cells. A half-cell has half as much heat capacity as a full-cell. An end-cell unit is composed of a cooling channel sandwiched in between full-cell and a half-cell. A mass flow rate distribution look-up-table is generated from a set of steady-state simulations obtained by running the full CFD model at different inlet manifold mass flow rate samples.
2016-04-05
Technical Paper
2016-01-0699
Jacob McKenzie, Wai K. Cheng
An ignition delay correlation encompassing the effects of temperature, pressure, residual gas, EGR, and lambda (on both the rich and lean sides) has been developed. The procedure uses the individual knocking cycle data from a boosted direct injection SI engine (GM LNF) operating at 1250 to 2000 rpm, 8-14 bar GIMEP, EGR of 0 to 12.5%, and lambda of 0.8 to 1.3 with a certification fuel (Haltermann 437, with RON=96.6 and MON=88.5). An algorithm has been devised to identify the knock point on individual pressure traces so that the large data set (of some thirty three thousand cycles) could be processed automatically. For lean and for rich operations, the role of the excess fuel, air, and recycled gas (which has excess air in the lean case, and hydrogen and carbon monoxide in the rich case) may be treated as effective diluents in the ignition delay expression.
2016-04-05
Technical Paper
2016-01-1212
Yupu Chen, Miaohua huang
Lithium-ion battery plays a key role in electric vehicles, which is critical to the system availability. One of the most important aspects in battery managements systems(BMS) in electric vehicles is the stage of health(SOH) estimation. The state of health (SOH) estimation is very critical to battery management system to ensure the safety and reliability of EV battery operation. The classical approach of current integration(coulomb counting) can not get the accurate values because of accumulative error. In order to provide timely maintenance and replacements of electric vehicles, several estimation approaches have been proposed to develop a reliable and accurate battery state of health estimation. A common drawback of previous algorithm is that the computation quantity is huge and not quite accurate, that is updated partially in this study.
2016-04-05
Technical Paper
2016-01-1197
Zhengbin Wu, Rongcheng Weng, Zhiqun zhang, Juan Li
Lithium-ion battery is in an increasing demand for alternative energy vehicles, grid storage systems and consumer electronics for its long cycle life, relatively high energy density and safety. It is important to achieve the accurate dynamic performance of lithium-ion battery for practical applications. Associating the electrochemical phenomena of a battery with electrical and non-electrical components, equivalent circuit models are normally more computation efficient compared to electrochemical models. In this paper, a novel equivalent circuit model for lithium-ion battery having inductive and capacitive components with the complex parameters is proposed. The corresponding imaginary part of these complex parameters represents the frequency-dependent dissipation characteristics from different electrochemical and physical aspects in this proposed battery model.
2016-04-05
Technical Paper
2016-01-0655
Farid Bahiraei, Amir Fartaj, Gholm-Abbas Nazri
Li-ion batteries are leading candidates for hybrid and electric vehicles as environmentally friendly means of transport. The main barriers for widely deployment of these batteries in electric vehicles are safety, cost, and poor low temperature performance, which are all challenges related to battery thermal management system (BTMS). Therefore, an effective thermal management strategy is crucial for enhancing the system lifetime and increasing vehicle range. In this study, a coupled thermal-electrochemical model for prismatic cells is primarily developed to simulate the battery cell chemistry and heat generation. This model is also used to investigate the effectiveness of active and passive cooling systems. The active cooling system under study utilizes cooling plates and water-glycol mixture as the working fluid while the passive cooling system incorporates a phase change material (PCM).
2016-04-05
Technical Paper
2016-01-0900
Sijia Zheng, Wen Fan
About 40% of the energy that is input to an internal combustion engine is lost in the exhaust as heat. Thermoelectric generators (TEGs) can be integrated into the power supply system of automobiles to recovery the heat energy in the exhaust gas, aiming at reducing the fuel consumption of the car and consequently reduce emissions. This paper examines the potential of TEGs to improve the fuel efficiency of conventional vehicles and hybrid electric vehicles (HEVs) and tries to quantify the improvement. Firstly, mathematic model of the TEG is constructed and Simulink model is built accordingly. Then the Simulink model of TEG system is integrated into the vehicle model. The vehicle simulation software ADVISOR is chosen as vehicle simulator and simulations are carried out considering three driving cycles. The results of the fuel consumption are compared and analyzed to quantify the fuel economy benefits, meanwhile, the emissions are check.
2016-04-05
Technical Paper
2016-01-0094
Jaya Gaitonde, R B Lohani
Photodetectors are important components in automotive industry. Sensitivity, speed, responsivity, quantum efficiency and power dissipation are the important characteristics of a photodetector. We report a high performance photodetector based on GaAs Metal- Semiconductor Field Effect Transistor (MESFET), with very high responsivity, high sensitivity, very high quantum efficiency, high speed and low power dissipation, surpassing their photodiode and phototransistor counterparts. A theoretical model of GaAs front illuminated Optical Field Effect transistor is presented. The photovoltaic and photoconductive effects have been taken into account. The gate of the OPFET device has been left open to make a reduction in the number of power supplies. The device shows high potential in automotive applications.
2016-04-05
Technical Paper
2016-01-0464
Lingyang Li, Wei Wu, Ji Chen, Jianpeng shi, Xicheng Wang, Liuhua Qian
In order to expand the product design and development capabilities of Electric Power Steering (EPS) system, a passenger car's simulation model integrated with EPS system model will be made, and do some analytical investigation in this paper. Through simplifying the architecture model of EPS system, the mathematical equation expressions of steering wheel and column, worm gear reducer, rack and pinion, steer-wheels, brushed DC electrical motor, and ECU assistance and compensation laws will be described. A number of tests on the EPS full system and subsystems and components will be executed. The tests' results will be used as the input parameters of the model, and then be used for model validations. After that, the EPS system model will be created. Since the most important part of control logic strategy is the top secret of steering assembly supplier and it could't be provided to OEM in details or not even a black-box model directly.
2016-04-05
Technical Paper
2016-01-0458
Jiawei Li, Gangfeng Tan, Yangjie Ji, Yongchi Zhou, Ziang Liu, Yingxiao Xu
This paper proposed a novel concept of Integrated Energy-recuperation retarder (IEER). Facing the conventional eddy current retarders’ (ECR) braking torque attenuation under high speed domain and the poor braking property of the regenerative brake (RGB) in low speed domain, the IEER is designed to take the advantages of both the ECR and the RGB to overcome their disadvantages. The IEER integrates the rotary eddy current retarder (RECR) and the RGB, both of which share a stator. Slots are grooved on the stator of the IEER, and armature-windings are inserted in slots. Poles are arranged on the rotator. Eddy currents are excited in the stator core, and the current is excited in the armature-windings. Braking torque of the IEER produced by stator core and armature-windings can stack together, and therefore the IEER can provide greater braking torque than the RECR. Besides, the IEER can recover electric energy from armature-windings.
2016-04-05
Technical Paper
2016-01-0565
SoDuk Lee, Charles Schenk, Joseph McDonald
As part of the U.S. Environmental Protection Agency (U.S. EPA) “Midterm Evaluation of Light-duty Vehicle Standards for Model Years 2022-2025 [1]”, the U.S. EPA is evaluating engines and assessing future engine technologies. Significant development time and resources are required for optimizing intake and exhaust cam Variable Valve Timing (VVT) timing, exhaust gas recirculation (EGR) flow rates, and compression ratios (CR) in order to improve the efficiency of engines as part of industry compliance with 2022 and later greenhouse gas (GHG) emissions standards. Mazda SkyActiv-G spark-ignition (SI) engines were selected by EPA for an internal engine development program based upon their high geometric compression ratio (14:1 in Europe and Japan, 13:1 in North America) and their use of a flexible valve train configuration with electro-mechanical phasing control on the intake camshaft.
2016-04-05
Technical Paper
2016-01-0285
Salah H. R. Ali, Mohammed A. H. Khalafalla, Ihab H. Naeim, Sarwat Z. A. Zahwi
Straightness deviation in dimensional metrology is an important fact in precision engineering. Optimization in straightness measurement using soft algorithm techniques is widely encountered solution in coordinate metrology. Estimating the uncertainty in geometrical feature measurement remains a necessary requirement to ensure high accurate metrology method especially in CMM measurement. In this work, we report on the uncertainty in the CMM measurement of spatial straightness feature for a slab. Straightness deviation has been measured precisely in 3D using CMM at NIS. The spatial straightness has been analyzed using a Particle Swarm Optimization (PSO) algorithm. The probability density distribution of the measured spatial straightness was developed using a Sequential Monte Carlo (SMC) technique; forming probability density histogram with 95% coverage interval representing an uncertainty in the straightness measurement.
2016-04-05
Technical Paper
2016-01-1622
Miroslav Mokry
Lagally outlined his theory in the early 1920s, with no particular application in mind. Several decades later it became near indispensable in naval hydrodynamics, for calculating forces and moments exerted by the boundaries of narrow channels on passing vessels, effects of the ground or free surface on submerged bodies, etc. In wind tunnel testing, Lagally's theory has never really ‘caught on’. Assuming the model to be small relative to the test section, preference was given to the evaluation of the aerodynamic force increment from the ambient pressure gradient. However, as will be demonstrated in the paper, this approach is inaccurate for wind tunnel testing of larger blockage-ratio models even when their virtual masses can be established. The essence of the method presented here is as follows. By the Lagally theorem, the force exerted on a solid body by an external source is equal to the mass flow rate of the source times the induced velocity at the source location.
2016-04-05
Technical Paper
2016-01-1303
Haiqing Xu, Chang JIN, HONG ZHOU, YI ZHOU
On the study of reducing the disturbance on driver’s attention induced by low frequency vehicle interior stationary noise, a subjective evaluation is firstly carried out by means of rank rating method which introduces Distraction Level as evaluation index. A visual-finger response test is developed to help evaluating person better recognize the Distraction Level during the evaluation. A non-linear BP neural network is then modeled for the prediction of subjective Distraction Level, in which linear sound pressure RMS amplitudes of five critical bands from 20 to 500Hz are selected as inputs of the model. Furthermore, active noise equalization (ANE) on Distraction Level is realized based on FXLMS algorithm that controls the five gain coefficients of each input of trained BP neural network model.
2016-04-05
Technical Paper
2016-01-1309
Yingping Lv, Yongchang Du, Yujian Wang
In this paper, analysis methods for brake squeal including substructure modal composition analysis and substructure modal parameters sensitivity analysis are presented. The methods are based on a new closed-loop coupling disc break model, where the coupled nodal pairs in each coupling interface are connected tightly. This assumption is different from other existing models in literatures, where the interface nodes are coupled through assumed springs. Based on this new model, two analysis methods are derived. Substructure modal composition analysis indicates the contribution of modes of each substructure to the noise mode. Substructure modal parameters sensitivity analysis calculates the sensitivity of each component’s modal frequencies and shape coefficients to the real part of eigenvalues. Finally, the presented analysis methods are applied to analysis a high frequency squeal problem of a squealing disc brake.
2016-04-05
Technical Paper
2016-01-0394
Minghuang Cheng, Norihiko Sawa
This paper describes the development of a fatigue life prediction method for Laser Screw Welding (LSW), which is used to assess the durability of automotive structures in the early design stages to shorten the vehicle development time. The LSW technology is a spot-type joining method such as resistance spot welding (RSW), and has been developed and applied to body-in-white structures in recent years. LSW can join metal panels even when a clearance exists between the panels. However, as a result of this favorable clearance-allowance feature of LSW, a concave shape may occur at the nugget part of the joint. These LSW geometric features, the concavity of nuggets and the clearance between panels, are thought to affect the local stiffness behavior of the joint. Therefore, while assessing the fatigue life of LSW, it is essential to estimate the influence adequately for the representation of the local stiffness behavior of the joint.
2016-04-05
Technical Paper
2016-01-1557
Francesco Castellani, Nicola Bartolini, Lorenzo Scappaticci, Davide Astolfi, Matteo Becchetti
Shock absorber is one of the most relevant sub-systems of the suspension system for a wide range of vehicles. Although a high level of development and tuning has been reached, in order to ensure high safety standards in almost every situation, some dynamic phenomena affecting vehicle handling or NHV can appear. The aim of present work is to improve a mathematical model using experimental data from a prototype of monotube shock absorber developed for research purposes. The model takes into account all the main features affecting the global performance of the device, such as non-linear behaviour and the presence of hysteresis loops. Actually, the most important parameters are analyzed, as flow and orifice coefficients of the valves, coefficients of mechanical compliance of the chambers and oil compressibility, dry and viscous friction coefficients.
2016-04-05
Technical Paper
2016-01-0100
Sushant Kishor Hingane
The high-end vehicles with latest technology and autonomous driving experience have to bear the cost of increasing number of sensors on-board. It would prove to be the most beneficial to reduce some of the sensors in vehicle and make use of other available resources, retaining the same functionality. This paper discusses a technique of estimating the weight of seat occupant from an already existing DC motor; without using additional pressure sensors. Passenger weight information is important for seat-belt reminder system as well as supplementary restrain system that will decide the air-bag deployment. A mathematical model for a series-type DC motor is developed and simulated using MATLAB. Further, results are shared of the lab experiment performed on a lower capacity motor and verified with the simulation results. Along with the comparison of the simulated data and sensor set-up results, a concluding linear relation is formulated.
2016-04-05
Technical Paper
2016-01-1113
Thorsten Arndt, Alex Tarasow, Christian Bohn, Guido Wachsmuth, Roland Serway
Higher demands on comfort and efficiency require a continuous improvement of the shift progress. During the launch and shift progress the clutch control is used to get a smooth and efficient behavior. In this short time of acting the shifting behavior can be rated. Many control concepts use a clutch characteristic to calculate the actuator signal based on the clutch torque. Therefore, a high quality of this characteristic is necessary. Because of the dynamic process during clutch engagement the clutch characteristic needs further information to reach a high accuracy for the control algorithm. In this paper an existing clutch torque characteristic is extended to a characteristic map where the clutch torque becomes a function of the current pressure in the clutch and the clutch slip. The extension of the torque characteristic describes the slip based dependencies, e.g. the friction coefficient.
2016-04-05
Technical Paper
2016-01-1037
Lars Eriksson, Vaheed Nezhadali, Conny Andersson
Modelbased systems engineering is becomming an important tool when meeting the challenges of developing the complex future vehicles that fulfill the custumers and legislators ever in- creasing demands for reduced pollutants and fuel consumption. To be able to work systematically and efficiently it is desirable to have a library of components that can be adjusted and adapted to each new situation. Turbochaged engines are complex and the compressor model serves as an in-depth example of how a library can be designed, incorporating the basic physics and al- lowing fine tuning as more information becomes available. A major part of the paper is the summary and compilation of a set of rules of thumb for compressor map extrapolation. The considerations discussed are extrapolation to surge, extrapla- tion to restriction region, and extrapolation out to choking.
2016-04-05
Technical Paper
2016-01-1546
Dongpil Lee, Kyongsu Yi, Bongchoon Jang, Sehyun Chang, Byungrim Lee
This paper describes a reference steering feel tracking algorithm for Electric-Power-Steering (EPS) system. Development of the EPS system with intended steering feel has been time-consuming procedure, because the feedforward map-based method has been applied to the conventional EPS system. However, in this study, a three-dimensional reference steering feel surface, which is determined from current vehicle states, is proposed. In order to track the proposed reference steering feel surface, sliding mode approach is applied to second-order steering dynamics model considering a coulomb friction model. An adaptive technique is utilized for robustness against uncertainties. In order to validate the proposed EPS control algorithm, hardware-in-the-loop simulation (HILS) has been conducted with respect to various steering tests (Weave, Transition, Flick, and Return-ability). It is shown that the reference steering feel is realized well by the proposed EPS control algorithm.
2016-04-05
Technical Paper
2016-01-0334
Lucas e Silva, Tennakoon Mudiyanselage Tennakoon, Mairon Marques, Ana M. Djuric
A new trend in automation is integration of collaborative robots. A collaborative robot or cobot is a robot that can safely and effectively interact with human workers while performing simple industrial tasks. Engineering Technology at Wayne State University offer several robotic courses, trainings and research in the advanced robotic lab. Recently we purchased a Baxter ® collaborative robot made by Rethink RoboticsTM. This Cobot is dual arm robot manipulator with vision based control. The goal of our research is to develop Matlab based toolbox for Baxter ®, which includes several modules: Kinematic, Jacobian matrix and singularity conditions, Dynamics of links, Dynamics of actuators and model based platform for control purposes. This Cobot has two arms and the calculation should be done for both arms. Doing the calculation for both arms individually, is very long and tedious process.
2016-04-05
Technical Paper
2016-01-1453
I-Hsuan Lee, Bi-Cheng Luan
Autonomous emergency braking (AEB) systems is one of the functions of the Advanced Driver Assists System to avoid or mitigate vehicle frontal collisions. Most of the previous studies focus on two-car scenario where the host vehicle monitors the distances to the vehicles in front, and automatically applies emergency brake when a collision is imminent. The purpose of this paper is to develop an Advanced-AEB control system that mitigates collisions in a multi-car scenario by computing the Time-to-Collision (TTC) to the vehicles in front as well as those to the vehicles behind using the concept of impedance control. A simple gain-scheduling PI controller was designed for the host vehicle to track the reference inputs generated by the impedance control. The preliminary simulation results demonstrate that the proposed AEB is effective in mitigating the collisions in a 3-car following scenario.
2016-04-05
Technical Paper
2016-01-1116
Branimir Skugor, Joško Deur, Vladimir Ivanovic
The automatic transmission gear ratios are set in order to meet vehicle speed and propulsion torque targets while ensuring good fuel economy, drivability, and driving comfort performance. Apart from determining appropriate values of transmission gear ratios (in the hardware design stage), it is also crucial to design and parameterize shift scheduling and shift control strategies. In the automotive practice, shift scheduling is commonly implemented through shift scheduling maps that are considered robust and intuitive. These maps are calibrated by highly-experienced engineers and, as such, they result in satisfactory vehicle performance. However, the achieved performance is still suboptimal, and the calibration process can be time consuming. In order to achieve optimal vehicle performance and to shorten the calibration time, it is possible to use model-based numerical optimization methods to determine optimal shift schedules for different driving scenarios.
2016-04-05
Technical Paper
2016-01-0031
Wenxu Niu, Ke Song, Yucheng He, Tong Zhang
X-in-the-loop (XiL) framework is a new validation concept for vehicle product development, which integrates different virtual and real components to improve the development efficiency. With XiL platform the requirements of reproducible test, optimization and validation, in which hardware, equipments and test objects are located in different places, could be realized. In the view of different location and communication form of hardware, equipments and test objects, time delay problem exists in the XiL platform, which could have a negative impact on development and validation process. In this paper, a simulation system of time delay prediction and compensation is founded with the help of BP neural network and RBF neural network. With this simulation system the effect of time delay in a vehicle dynamic model as well as tests of geographically distributed vehicle powertrain system is improved during the validation process.
2016-04-05
Technical Paper
2016-01-0103
Ludwig Brabetz, Mohamed Ayeb, Oliver Baumgarten
The topology of an EDS, defined by the routing paths and by the location of the distribution boxes and the inline connectors, has a strong impact on weight and required amount of material, especially of copper, as well as on the manufacturing- and assembly time. Although a good part of the routing and packaging is fixed due to technical reasons and carry-over situations, in general there are enough optional paths and locations to allow up to several thousand alternative topologies. For these reasons, an optimization is possible as well as important. For such an optimization, in this paper a method is presented to minimize both the required material, e.g. length of the wires and copper, and the overall length of the wire bundles by altering the topology.
2016-04-05
Journal Article
2016-01-0656
Jung Hyun Kim, Taewoo KIM, SungJin Park, JungJae HAN, Choongsoo Jung, Young rock Chung, Sangsoo Pae
In cold start driving cycles, high viscosity of the lubrication oil (engine oil) increases the mechanical friction losses compared with warmed up condition. Thus, an engine oil warm up system can provide the opportunity to reduce the mechanical friction losses during cold start. In this study, an engine oil heater using EGR is used for the fast warm up of the engine oil. This paper presents the effect of the engine oil heater on the fuel economy and emissions over a driving cycle (NEDC). A numerical model is developed to simulate the thermal response of the powertrain using multi-domain 1-D commercial powertrain simulation software (GT-Suite) and it is calibrated using test data from a full size sedan equipped with a 2.0L diesel engine. The model consists of an engine model, coolant circuit model, oil circuit model, engine cooling model, friction model, and ECU model.
2016-04-05
Technical Paper
2016-01-1315
Yongchang Du, Yingping Lv, Yujian Wang, Pu Gao
Closed-loop coupling model, based on complex eigenvalue analysis, is one of the most popular and effective methods for brake squeal analysis. In the model, coupling springs are used to represent the normal contacting force between coupled nodes. This assumption is the foundation of the model. But the physical meaning of coupling spring was seldom discussed and there’s no systematic method to determine the value of spring stiffness. This paper presents a new closed-loop coupling disc brake squeal model based on finite element component model and modal synthesis technique. Different from the traditional model, where the two nodes in a coupled node-pair are connected through a spring, in the new model they are assumed to be remain contacted tightly during vibration. Details of the model, including force analysis, coordinate reduction and transformation and complex eigenvalue decomposition are given.
2016-04-05
Technical Paper
2016-01-1544
Dexin Wang, Frank Esser
Evaluation of electric steering (EPAS) system performance using vehicle specific load conditions is important for steering system design validation and vehicle steering performance tuning. Using real-time vehicle dynamics math models is one of approaches for steering HIL testing. However achieving a good correlation of simplified math models with real vehicle dynamics is a challenge. Using rack force models from measured steering tie rod forces is an effective data-driven modeling method for testing EPAS systems under vehicle specific load conditions.Rack force models are identified from measurements for those test maneuvers for evaluating vehicle steering performance.
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