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Viewing 121 to 150 of 15354
2017-03-28
Technical Paper
2017-01-0174
Ravi Rungta, Noori Pandit
Abstract A simple and rapid immersion type corrosion test has been successfully developed that discriminates corrosion performance in condensers from various suppliers and with differing manufacturing processes. The goal is to develop a test specification that will be included in the Ford corrosion specification for condensers so that condensers received from various suppliers may be evaluated rapidly for their relative corrosion performance to each other. Sections from condensers from Supplier A (tube is silfluxed), Supplier B (tube is zinc arc sprayed), and Supplier C (bare folded tube with no zinc for corrosion protection) were tested in 2% v/v hydrochloric acid for 16, 24 and 48 hours. The results showed that in terms of corrosion performance, zinc arc sprayed Supplier B condenser performed the worst while Supplier C condenser performed the best with Supplier A in between.
2017-03-28
Technical Paper
2017-01-0328
Yunkai Gao, Genhai Wang, Jingpeng Han
Abstract The multi-body dynamics simulation and physical iteration were carried out based on the 4-channel road simulation bench, the solution of fatigue test bench which was suitable for cab with frame and suspension was designed. Large load and displacement above the suspension can be loaded on the test bench, and the same weak position of cab exposed on the road test can be assessed well on the fatigue test bench. The effectiveness of the bench test solution was verified though comparative study. And it has important reference for the same type of cab assembly with suspension in the fatigue bench test. According to the durability specifications of cab assembly, a multi-body dynamics model with a satisfactory accuracy was built. And the fixture check and virtual iteration analysis were used to verify the effectiveness of the solution. According to the road load signal analysis and multi-body dynamics analysis results, the test bench with linear guide and spherical joint was built.
2017-03-28
Technical Paper
2017-01-1147
Hyunjun Kim, Jingeon Kang, Dongsuk Kum
Abstract Input- and output-split hybrids using a single planetary gear (PG) can provide high fuel economy, but they tend to suffer from low acceleration performance. In order to improve their acceleration performance, speed reduction (multiplication) gears (SRG/SMG) have often been employed in various mass-produced split hybrids. In fact, adding one SRG (SMG) to input- or output-split hybrids can improve not only the acceleration performance, but also the fuel economy. Nevertheless, the full potentials of using SRGs (SMGs) have not yet been thoroughly investigated because the design space of input- and output-split configurations using one SRG (SMG) is huge; 432 configurations can be generated using two PGs where one PG is used as an SRG/SMG. Thus, in order to investigate the impacts of SRG (SMG) within a reasonable time, an efficient analysis procedure is required.
2017-03-28
Technical Paper
2017-01-1237
Ahmad Arshan Khan, Michael J. Kress
Abstract For high performance motor controls applications such as electric vehicles, accurate motor parameter knowledge is required. Motor parameters like d-axis inductance, q-axis inductance, resistance and permanent magnet flux linkage are difficult to obtain and measure directly. These four parameters can be reduced to three parameters resistance, d-axis and q axis flux linkage. In this paper, a new scheme is proposed to approximate d-axis and q-axis flux linkage using measured torque, dq-axis measured current, and dq-axis voltage commands to the inverter. d-axis and q-axis flux linkages are estimated over a range of d-axis and q-axis currents that fully map the desired motor operation region.
2017-03-28
Technical Paper
2017-01-1239
Naoya Take, Takuya Kadoguchi, Masao Noguchi, Kimihiro Yamanaka
Abstract Power modules are used to operate three-phase alternating current motors in hybrid vehicles and electric vehicles. Good fuel efficiency and high power density are required in the field of hybrid vehicles. To achieve this goal, the miniaturization of the power module will be necessary. This trend may make a current density, which is created by insulated gate bipolar transistors (IGBTs) and free wheel diodes (FWDs), higher in power modules. Solder is often used as the joint material of power modules. It is known that a current density larger than 10 kA/cm2 causes solder electromigration. This phenomenon may cause delamination of the joint area. In addition, the ambient temperature has an influence on electromigration. The temperature of an engine compartment is high, so it is likely to cause electromigration. However, the current density of the double-sided cooling power modules in 2007 with solder joint is lower than 0.4 kA/cm2, and this value is lower than 10 kA/cm2.
2017-03-28
Technical Paper
2017-01-1245
Takamitsu Tajima, Hideki Tanaka, Takeo Fukuda, Yoshimi Nakasato, Wataru Noguchi, Yoshikazu Katsumasa, Tomohisa Aruga
Abstract The use of electric vehicles (EV) is becoming more widespread as a response to global warming. The major issues associated with EV are the annoyance represented by charging the vehicles and their limited cruising range. In an attempt to remove the restrictions on the cruising range of EV, the research discussed in this paper developed a dynamic charging EV and low-cost infrastructure that would make it possible for the vehicles to charge by receiving power directly from infrastructure while in motion. Based on considerations of the effect of electromagnetic waves, charging power, and the amount of power able to be supplied by the system, this development focused on a contact-type charging system. The use of a wireless charging system would produce concerns over danger due to the infiltration of foreign matter into the primary and secondary coils and the health effects of leakage flux.
2017-03-28
Technical Paper
2017-01-1220
Ahmad Arshan Khan
Abstract In an interior permanent magnet machine, magnet temperature plays a critical role in determining optimal current control trajectory. Monitoring magnet temperature is a challenging task. In lab and various specialized applications, infrared sensors or thermocouples are used to measure the temperature. But it adds cost, maintenance issues and their integration to electric machine drives could be complicated. To tackle issues due to sensor based methods, various sensorless model based approaches are proposed in the literature recently such as flux observer, high-frequency signal injection, and thermal models, etc. Although magnet temperature monitoring received a lot of attention of researchers, very few papers give a detailed overview of the effects of magnet temperature on motor control from a controls perspective. This paper discusses the impact of magnet temperature variation on Maximum Torque per Ampere control and Flux Weakening Control trajectory.
2017-03-28
Technical Paper
2017-01-1555
Mirosław Jan Gidlewski, Krystof JANKOWSKI, Andrzej MUSZYŃSKI, Dariusz ŻARDECKI
Abstract Lane change automation appears to be a fundamental problem of vehicle automated control, especially when the vehicle is driven at high speed. Selected relevant parts of the recent research project are reported in this paper, including literature review, the developed models and control systems, as well as crucial simulation results. In the project, two original models describing the dynamics of the controlled motion of the vehicle were used, verified during the road tests and in the laboratory environment. The first model - fully developed (multi-body, 3D, nonlinear) - was used in simulations as a virtual plant to be controlled. The second model - a simplified reference model of the lateral dynamics of the vehicle (single-body, 2D, linearized) - formed the basis for theoretical analysis, including the synthesis of the algorithm for automatic control. That algorithm was based on the optimal control theory.
2017-03-28
Technical Paper
2017-01-0160
Longjie Xiao, Tianming He, Gangfeng Tan, Bo Huang, Xianyao Ping
Abstract While the car ownership increasing all over the world, the unutilized thermal energy in automobile exhaust system is gradually being realized and valued by researchers around the world for better driving energy efficiency. For the unexpected urban traffic, the frequent start and stop processes as well as the acceleration and deceleration lead to the temperature fluctuation of the exhaust gas, which means the unstable hot-end temperature of the thermoelectric module generator (TEG). By arranging the heat conduction oil circulation at the hot end, the hot-end temperature’s fluctuation of the TEG can be effectively reduced, at the expense of larger system size and additional energy supply for the circulation. This research improves the TEG hot-end temperature stability by installing solid heat capacity material(SHCM) to the area between the outer wall of the exhaust pipe and the TEG, which has the merits of simple structure, none energy consumption and light weight.
2017-03-28
Technical Paper
2017-01-0371
Raju Gandikota, Amit Nair, Kurt Miller
Abstract Testing elastomeric materials that undergo large strains pose challenges especially when establishing failure criteria. The failure criterion for composites and polymers based on finite elasticity published by Feng (1) requires testing under uniaxial and biaxial stretching modes. The classic inflation of a circular disk for biaxial stretch mode poses stability and safety challenges. The test can also be sensitive to end constraints resulting in failure of materials at the constraints. Biaxial stretching with a hemispherical punch is explored in this work. The biaxial stretching allows controlled and repeatable testing. It establishes a clear and reliable failure mechanism of the material at the poles. Through a combination of testing and numerical methods, the stretch ratios and its relation to failure have been established. The method greatly simplifies testing and provides reliable data for a failure criterion for elastomers in numerical modeling.
2017-03-28
Technical Paper
2017-01-0341
Seyyedvahid Mortazavian, Javid Moraveji, Reda Adimi, Xingfu Chen
Abstract In this study, a finite element analysis method is developed for simulating a camshaft cap punching bench test. Stiffness results of simulated camshaft cap component are correlated with test data and used to validate the model accuracy in terms of material and boundary conditions. Next, the method is used for verification of cap design and durability performance improvement. In order to improve the computational efficiency of the finite element analysis, the punch is replaced by equivalent trigonometric distributed loads. The sensitivity of the finite element predicted strains for different trigonometric pressure distribution functions is also investigated and compared to strain gage measured values. A number of equivalent stress criteria are also used for fatigue safety factor calculations.
2017-03-28
Technical Paper
2017-01-0534
Bojan S. Jander, Roland Baar
Abstract The knowledge of thermal behavior of combustion engines is extremely important e.g. to predict engine warm up or to calculate engine friction and finally to optimize fuel consumption. Typically, thermal engine behavior is modeled using look-up tables or semi-physical models to calculate the temperatures of structure, coolant and oil. Using look-up tables can result in inaccurate results due to interpolation and extrapolation; semi-physical modeling leads to high computation time. This work introduces a new kind of model to calculate thermal behavior of combustion engines using an artificial neural network (ANN) which is highly accurate and extremely fast. The neural network is a multi-layered feed-forward network; it is trained by data generated with a validated semi-physical model. Output data of the ANN-based model are calculated with nonlinear transformation of input data and weighting of these transformations.
2017-03-28
Technical Paper
2017-01-0626
LeeAnn Wang, George Garfinkel, Ahteram Khan, Mayur Harsha, Prashanth Rao
Abstract When a driver completes an aggressive drive cycle on a hybrid vehicle, the High Voltage (HV) battery system may be at risk of exceeding the power limit temperature, due to continuous absorption of radiative and convective heat from the environment, such as from exhaust and pavement, even after key-off. In such a case, in the absence of active cooling, the vehicle may not be keyed-on until battery temperatures are reduced below critical values. A transient thermal analysis is conducted on a HV battery system to simulate the key-off operation using an effective Computational Fluid Dynamics (CFD) methodology. Two stages are considered in this methodology to capture the complexity of the geometry and the multiple phenomena that need to be simulated in the model. The introduced modeling technique can be used for Full Hybrid Electric Vehicle (FHEV) and Plug-in Hybrid Electric Vehicle (PHEV) transient key-off situations.
2017-03-28
Technical Paper
2017-01-0182
Gautam Peri, Saravanan Sambandan, S. Sathish Kumar
Abstract Cool down of a passenger vehicle cabin is a preferred method to test the efficiency of the vehicle HVAC (Heating, Ventilation and Air Conditioning) system. The intended primary objective of a passenger vehicle air conditioning system is to ensure thermal comfort to the passengers seated inside at all prevailing conditions. Presently 1-D analysis plays a major role in determining the conformation of the selected system to achieve the desired results. Virtual analysis thus saves a lot of time and effort in predicting the system performance in the initial development phase of the vehicle HVAC systems. A variety of parameters play an important role in achieving the above thermal comfort. Thermal comfort is measured using the Human comfort sensor for all the passengers seated inside.
2017-03-28
Technical Paper
2017-01-0164
Venkatesan Muthusamy, S. Sathish Kumar, Saravanan Sambandan
Abstract In an automotive air-conditioning (AC) system, upfront prediction of the cabin cool down rate in the initial design stage will help in reducing the overall product development (PD) time. Vehicle having higher seating capacity will have higher thermal load and providing thermal comfort to all passengers uniformly is a challenging task for the automotive HVAC (Heating Ventilation and Air conditioning) industry. Dual HVAC unit is generally used to provide uniform cooling to a large cabin volume. One dimensional (1D) simulation is being extensively used to predict the HVAC performance during the initial stage of PD. The refrigerant loop with components such as compressor, condenser, TXV and evaporator was modeled. The complicated vehicle cabin including the glazing surfaces and enclosures were modeled as a three row duct system using 1D tool AMESim®. The material type, density, specific heat capacity and thermal conductivity of the material were specified.
2017-03-28
Technical Paper
2017-01-0166
Noori Pandit
Abstract The effects of substituting a 12 mm thick subcool on top condenser in place of a 16 mm subcool on bottom condenser are evaluated in a vehicle level AC pull down test. The A to B testing shows that a thinner condenser with subcool on top exhibits no degradation in AC performance while resulting in a lower total system refrigerant charge. The results are from vehicle level tests run in a climatically controlled vehicle level wind tunnel to simulate an AC pull down at 43°C ambient. In addition to cabin temperature and AC vent temperatures, comparison of compressor head pressures was also done. The conclusion of the study was that a standard 16 mm thick subcool on bottom IRD condenser can be replaced by a 12 mm thick subcool on top IRD condenser with no negative effects on performance.
2017-03-28
Technical Paper
2017-01-1410
Richard F Lambourn, James Manning
Abstract It can happen, following a collision between a car and a pedestrian or in a deliberate assault with a motor vehicle, that the pedestrian comes to be caught or wedged beneath the car, and that the driver then travels on for a considerable distance, afterwards claiming to have been unaware of the presence of the person. However, police, lawyers and jurors are often incredulous that the driver should not have been able to “feel” that there was something underneath his car. The authors have investigated the matter by carrying out practical tests with suitable cars and dummies. This paper describes instrumented tests performed by the authors following one such incident, and gives accounts of two previous incidents investigated in a more subjective fashion. The general conclusion is that the effect on the behavior of the car is very small and that a driver might indeed be unaware that there was a person trapped beneath them.
2017-03-28
Technical Paper
2017-01-1240
Koki Matsushita
Abstract For the purpose of improving vehicle fuel efficiency, it is necessary to reduce energy loss in the alternator. We have lowered the resistance of the rectifying device and connecting components, and control the rectifying device with an IC to reduce rectification loss. For the package design, we have changed the structure of the part on which the rectifying device is mounted into a high heat dissipation type. The new structure has enabled optimizing the size of the rectifying device, resulting in the reduction of size of the package. In addition, the rectifying device is mounted using a new soldering material and a new process, which has improved the reliability of the connection. Moreover, since the alternator has introduced a new system, the controller IC has a function for preventing malfunction of the rectifying device and a function for detecting abnormalities, in order to ensure safety.
2017-03-28
Technical Paper
2017-01-1231
Chun Tang, Natee Limsuwan, Nurani Chandrasekhar, Zhichun Ma, Jacob Krizan, Joel Hetrick, Wei Wu
Abstract The current of an electric machine driven by PWM switching inverter is not ideal sinusoidal, containing different levels of harmonics. The current harmonics have important impact on the electrical machine torque ripple which could translate into transmission and vehicle level Noise Vibration and Harshness (NVH). In this work, the current waveforms were measured from dyno test at prescribed torque and speed levels, and the electric machine torque ripple was computed with the measured current. This paper will focus on the investigation of the current harmonics behaviors and features at various torque and speed conditions, the impact on torque ripple, and the possible mitigation method to reduce torque ripple.
2017-03-28
Journal Article
2017-01-1154
Jimmy Kapadia, Daniel Kok, Mark Jennings, Ming Kuang, Brandon Masterson, Richard Isaacs, Alan Dona, Chuck Wagner, Thomas Gee
Abstract The automotive industry is rapidly expanding its Hybrid, Plug-in Hybrid and Battery Electric Vehicle product offerings in response to meet customer wants and regulatory requirements. One way for electrified vehicles to have an increasing impact on fleet-level CO2 emissions is for their sales volumes to go up. This means that electrified vehicles need to deliver a complete set of vehicle level attributes like performance, Fuel Economy and range that is attractive to a wide customer base at an affordable cost of ownership. As part of “democratizing” the Hybrid and plug-In Hybrid technology, automotive manufacturers aim to deliver these vehicle level attributes with a powertrain architecture at lowest cost and complexity, recognizing that customer wants may vary considerably between different classes of vehicles. For example, a medium duty truck application may have to support good trailer tow whereas a C-sized sedan customer may prefer superior city Fuel Economy.
2017-03-28
Journal Article
2017-01-1170
Tong Zhang, Chen Wang, Wentai Zhou, Huijun Cheng, Haisheng Yu
Abstract Because a compound power-split transmission is directly connected to the engine, dramatic fluctuations in engine output torque result in strong jerks and torque losses when the hybrid vehicle is in mode transition from electric drive mode to hybrid drive mode. In order to enhance ride comfort and reduce the output torque gap during mode transition process, a brake clutch assisted coordinated control strategy was developed. Firstly, the dynamic plant model of the power-split vehicle including driveline model, engine ripple torque and brake clutch torque was deduced. Secondly, the brake clutch assisted mode transition process was analyzed, and the output torque capability was compared between cases of both brake clutch assisted and unassisted mode transition process. Thirdly, a coordinated control strategy was designed to determine the desired motor torque, brake clutch torque, engine torque, and the moment of fuel injection.
2017-03-28
Technical Paper
2017-01-1427
Daniel Koch, Gray Beauchamp, David Pentecost
Abstract Tire disablement events can cause a drag force that slows a vehicle. In this study, the magnitude of the deceleration was measured for different phases of 29 high speed tire tread separation and air loss tests. These deceleration rates can assist in reconstructing the speed of a vehicle involved in an accident following a tire disablement.
2017-03-28
Technical Paper
2017-01-0331
Qiuren Chen, Haiding Guo, Katherine Avery, Xuming Su, HongTae Kang
Abstract Fatigue crack growth tests have been carried out to investigate the mixed mode fatigue crack propagation behavior of an automotive structural adhesive BM4601. The tests were conducted on a compound CMM (Compact Mixed Mode) specimen under load control with 0.1 R ratio and 3Hz frequency. A long distance moving microscope was employed during testing to monitor and record the real time length of the fatigue crack in the adhesive layer. The strain energy release rates of the crack under different loading angles, crack lengths and loads were calculated by using finite element method. The pure mode I and mode II tests show that an equal value of mode I strain energy release rate results in over ten times higher FCGR (Fatigue Crack Growth Rate) than the mode II stain energy release rate does. The mixed mode tests results show that under a certain loading angle, the mixed mode FCGR is changed by changing the load, which is contrary to the find in pure mode I and mode II tests.
2017-03-28
Technical Paper
2017-01-1066
Christoph Beerens, Alexander Mueller, Kimm Karrip
Abstract As emissions regulations and carbon footprint are more and more demandingly controlled, thermal efficiency of engine components must be optimized. Valve group components have to allow for ever increasing temperatures, endure aggressive condensates or even contribute directly to rising efficiency and emissions demands. Even with integrated and cooled exhaust manifolds, the exhaust valves are meeting full combustion temperatures, especially for stoichiometric combustion. MAHLE has developed a new technology in order to measure valve temperatures in real time, i.e. Transient Valve Temperature Measurement (TVTM). This is a complex methodology using thermocouples installed inside of the valves, offering the possibility to run the engine at different conditions, without any functional changes in the valve train system at all. Specifically valve rotation is not affected and thus temperatures all around the valve seat can be captured during rotation.
2017-03-28
Technical Paper
2017-01-1226
Nurani Chandrasekhar, Chun Tang, Natee Limsuwan, Joel Hetrick, Jacob Krizan, Zhichun Ma, Wei Wu
Abstract Noise and Vibration (NVH) characteristic of an electric machine (e-Machine) is the outcome of complex interaction between source level disturbances and the surrounding structure to which the e-Machine is attached. Key e-Machine metrics that objectively quantify source level disturbance include torque ripple and radial electro-magnetic forces. These disturbances can radiate directly from the e-Machine housing (air-borne component) and also can be transmitted through the structural attachments like stator bolts, stator ring, powertrain mounts etc. (structure-borne component). In the e-machine driven by PWM switching inverter, current is not perfectly sinusoidal but contain different level of harmonics. Current harmonics impact Torque ripple, which in turn would translate into undesirable noise and vibration. There is very limited literature referencing the influence of current harmonics on torque ripple and e-machine NVH.
2017-03-28
Technical Paper
2017-01-0134
Jan Eller, Heinrich Reister, Thomas Binner, Nils Widdecke, Jochen Wiedemann
Abstract There is a growing need for life-cycle data – so-called collectives – when developing components like elastomer engine mounts. Current standardized extreme load cases are not sufficient for establishing such collectives. Supplementing the use of endurance testing data, a prediction methodology for component temperature collectives utilizing existing 3D CFD simulation models is presented. The method uses support points to approximate the full collective. Each support point is defined by a component temperature and a position on the time axis of the collective. Since it is the only currently available source for component temperature data, endurance testing data is used to develop the new method. The component temperature range in this data set is divided in temperature bands. Groups of driving states are determined which are each representative of an individual band. Each of the resulting four driving state spaces is condensed into a substitute load case.
2017-03-28
Technical Paper
2017-01-0260
Yuanying Wang, Heath Hofmann, Denise Rizzo, Scott Shurin
Abstract This paper presents a computationally-efficient model of heat convection due to air circulation produced by rotor motion in the air gap of an electric machine. The model calculates heat flux at the boundaries of the rotor and stator as a function of the rotor and stator temperatures and rotor speed. It is shown that, under certain assumptions, this mapping has the homogeneity property. This property, among others, is used to pose a structure for the proposed model. The coefficients of the model are then determined by fitting the model to the results of a commercial Computational Fluid Dynamics (CFD) simulation program. The accuracy of the new model is compared to the CFD results, shown an error of less than 0.3% over the studied operating range.
2017-03-28
Technical Paper
2017-01-0121
Zhijia Yang, Jesus PradoGonjal, Matthew Phillips, Song Lan, Anthony Powell, Paz Vaqueiro, Min Gao, Richard Stobart, Rui Chen
Abstract Thermoelectric generator (TEG) has received more and more attention in its application in the harvesting of waste thermal energy in automotive engines. Even though the commercial Bismuth Telluride thermoelectric material only have 5% efficiency and 250°C hot side temperature limit, it is possible to generate peak 1kW electrical energy from a heavy-duty engine. If being equipped with 500W TEG, a passenger car has potential to save more than 2% fuel consumption and hence CO2 emission reduction. TEG has advantages of compact and motionless parts over other thermal harvest technologies such as Organic Rankine Cycle (ORC) and Turbo-Compound (TC). Intense research works are being carried on improving the thermal efficiency of the thermoelectric materials and increasing the hot side temperature limit. Future thermoelectric modules are expected to have 10% to 20% efficiency and over 500°C hot side temperature limit.
2017-03-28
Technical Paper
2017-01-0276
Lev Klyatis
Abstract This paper considers the situation in the laboratory testing: different stress types and accelerated testing, including accelerated reliability/durability testing, accelerated life testing, reliability testing, proving grounds, vibration, temperature, voltage, humidity, and others. In comparison with field situation, most of these testing simulate only one or part of the field input influences. One uses often not accurately the theory of physics-of-degradation process or failures for comparison of the field results with laboratory results. This situation will be considered with practical examples. It will be demonstrated that often used laboratory testing does not offer the possibility for successful prediction of product performance during service life As a result, there are many complaints, recalls, and less profit than was predicted during design and manufacturing. It will be shown how one can improve this situation..
2017-03-28
Technical Paper
2017-01-1007
Piotr Bielaczyc, Andrzej Szczotka, Joseph Woodburn
Abstract This paper reports testing conducted on multiple vehicle types over two European legislative driving cycles (the current NEDC and the incoming WLTC), using a mixture of legislative and non-legislative measurement devices to characterise the particulate emissions and examine the impact of the test cycle and certain vehicle characteristics (engine/fuel type, idle stop system, inertia) on particulate emissions. European legislative measurement techniques were successfully used to quantify particle mass (PM) and number (PN); an AVL Microsoot sensor was also used. Overall, the two driving cycles used in this study had a relatively limited impact on particulate emissions from the test vehicles, but certain differences were visible and in some cases statistically significant.
Viewing 121 to 150 of 15354