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2015-04-14
Technical Paper
2015-01-0661
Jianwang Shao, Xian Wu, Na Wei, Ding Wang, Guoming Deng, Ming Xu
An increasing demand for vehicle noise control has been proposed and at the same time, vehicle weight and fuel economy have become critical for the automotive industry. The methodology of statistical energy analysis (SEA) is used to balance both light weight and high noise insulation performance. In this paper, the vehicle dash and floor sound package systems, which are two of the major paths for vehicle interior noise, are studied and optimized by CAE and testing technology. Two types of sound package which are the conventional insulation system and the lightweight one are chosen for the vehicle dash and floor system. The vehicle dash and floor systems are modeled by SEA and the transmission loss (TL) of the dash and floor system is analyzed, respectively. Several influence factors of the TL are also analyzed, such as sound package coverage, the leaks, etc.
2015-04-14
Technical Paper
2015-01-0442
Sudhi Uppuluri, Ajay Naiknaware
Abstract: With increasing pressure to meet CAFE standards, various strategies are being developed to actively manage the vehicle drag and engine thermal performance to squeeze out additional fuel economy performance from existing vehicle. This paper develops on the previous work presented at this conference and discusses the sensitivity of key vehicle parameters that affect the engine thermal performance and fuel economy of the vehicle. The sensitivity analysis is based on a vehicle level system model that captures the entire engine thermal model and transient behavior of various key components such as the thermostat, the active grill shutter and accessory loads. Results discussed in this paper provides guidance on which variables have the most affect on fuel economy and which variables must be tightly controlled to improve the robustness and stability of the design.
2015-04-14
Technical Paper
2015-01-1230
Ahmed Imtiaz Uddin, Jerry Ku
It is well known that thermal management is a key factor in design and performance analysis of Lithium-ion (Li-ion) battery, which is widely adopted for hybrid and electric vehicles. In this paper, an air cooled battery thermal management system design has been proposed and analyzed for mild hybrid vehicle application. Computational fluid dynamics (CFD) analysis was performed using CD-adapco’s STAR-CCM+ solver and Battery Simulation Module (BMS) application to predict the temperature distribution within a module comprised of twelve 40Ah Superior Lithium Polymer Battery (SLPB) cells connected in series. The cells are cooled by air through aluminum cooling plate sandwiched in-between every pair of cells. The cooling plate has extended the cooling surface area exposed to cooling air flow. Cell level electrical and thermal simulation results were validated against experimental measurements.
2015-04-14
Technical Paper
2015-01-0505
Miguel Angel Reyes Belmonte, Colin D. Copeland, Drummond Hislop, George Hopkins, Adrian Schmieder, Scott Bredda, Sam Akehurst
Pressure and temperature levels within a modern internal combustion engine cylinder have been pushing at the limits of traditional materials and design. These operative conditions are due to the stringent emission and fuel economy standards that are forcing automotive engineers to develop engines with much higher power density ratios. In this scenario, downsized, turbocharged engines are an important technology to meet the future demands on transport efficiency. It is well known that within downsized turbocharged gasoline engines, thermal management becomes a vital issue for durability and combustion stability. In order to contribute to the understanding of engine thermal management, a conjugate heat transfer analysis of a downsized gasoline piston engine has been performed. The intent was to study the design possibilities afforded by the use of the Selective Laser Melting (SLM) additive manufacturing process.
2015-04-14
Technical Paper
2015-01-1753
Mario Vila Millan, Stephen Samuel
Nanofluids and thermal management strategy for Automotive Application Mario Vila Millan, Stephen Samuel Oxford Brookes University, United Kingdom Stringent emission norms introduced by the legislators over the decades have forced the automotive manufacturers to improve the fuel economy and emission levels of their engine continuously. This constant improvement leads to increased use of smart systems where components are controlled by the engine management systems to get a desired and optimized performance. Therefore, the emission levels of the modern engines are significantly lower than pre-1990 engines. However, the improvement in fuel economy is marginal when compared to that of the scale of improvement achieved for reducing emission levels. For example, approximately 30% of the total energy in the fuel is still being wasted through the cooling systems in the modern engines during normal operating conditions. This is even worse during the engine warm up.
2015-04-14
Technical Paper
2015-01-1122
Kengo Yabe, Toru Inagaki, Takashi Kondo
Seat vibration when the vehicle is idling and when it is in motion has been reduced by using a floating seat that controls the resonance frequencies. The resonance frequency is controlled by replacing the structures of the seat-mounting unit with floating structures using rubber bushings. Partly replacing the mounting unit with floating structures makes it possible to control the resonance frequencies of the entire seat. The issue of balancing vibration reduction with strength and durability and crash safety performance due to fitting rubber bushings to the seat-mounting unit was addressed using stopper structures optimized for each type of input. To adopt a floating seat into an actual vehicle, the floating structure and conventional foot bracket are combined. This combined foot bracket not only makes it easy to assemble floating structure into the seat, but also makes it possible to keep the seat weight almost the same as a conventional seat.
2015-04-14
Technical Paper
2015-01-0717
Anindya Deb, G S Venkatesh, Ashok Mache
The usage of lightweight materials such as plastics and their derivatives continues to increase in automobiles driven by the urgency for weight reduction. For structural performance, body components such as A-pillar or B-pillar trim, instrument panel, etc. have to meet various requirements including resistance to penetration and energy absorption capability under impact indentation. A range of plain and reinforced thermoplastics and thermosetting plastics has been considered in the present study in the form of plates which are subject to low velocity perforation in a drop-weight impact testing set-up with a rigid cylindrical indenter fitted to a tup. The tested plates are made of polypropylene (PP), nanoclay-reinforced PP of various percentages of nanoclay content, wood-PP composites of different volume fractions of wood fiber, a jute-polyester composite, and a hybrid jute-polyester reinforced with steel.
2015-04-14
Technical Paper
2015-01-1708
Tibor Kiss, Jason Lustbader, Daniel Leighton
For electric vehicles (EVs), there is a great need for highly optimized thermal management systems. Due to the relative shortage of waste heat, heating the passenger cabin in electric vehicles is difficult. Cooling the cabin can take a high portion of the energy available in the battery, significantly reducing vehicle efficiency and range. The range reduction can be as much as 50% by at least one report. Therefore, compared to IC engine driven vehicles, different heating methods and more efficient cooling methods are needed, which can make the electric vehicle’s thermal management system more complex. The more complex systems typically allow various alternative modes of operation which can be selected based on driving and ambient conditions. Investigating a number of system alternatives and determining the best ranges for the various operating modes with experimental methods can be very time consuming.
2015-04-14
Technical Paper
2015-01-1713
Manfred Klaus Kirschning, Frank Reußwig
In recent years, the automotive industry has taken many efforts to satisfy the market requirements of reducing fuel consumption and the emission of pollutants. In consequence engines had to be compacted and many additional modules had to be integrated into the confines of tightly packed engine compartments. The narrow confines also limited the options for piping options, for instance with preformed rubber tubes or oil flow and return pipes. Many of these components are designed for a maximum permanent temperature of 140°C to 180°C only. Other components, for example oil pipes, cannot be applied in settings with temperatures higher than 140°C because of the cracking of the hydrocarbon molecules.
2015-04-14
Technical Paper
2015-01-1694
Jun Li, Predrag Hrnjak
This paper presents results of the visualization of the separation in the vertical header of the automotive condenser. A prototype of a heat exchanger was made that has inlet in the middle of the header, with 21 microchannel tubes as the first pass. In the second header liquid separates and leaves through 4 microchannel tubes beneath while mostly vapor leaves through 11 microchannel tubes on the top as another exit. That way the 2nd pass has liquid below first pass and vapor above it. R134a and R1234yf are used in the tests. Mass flow was in the range 30 - 80 g/s (mass flux 170 kg/m2·s to 450 kg/m2·s) and quality at the inlet to second header over a range of 0.1 to 0.3, to see their impact on the separation of two-phase flow inside the transparent header. Visualization data were taken to better understand and define the physical parameters that dominate the separation phenomena.
2015-04-14
Technical Paper
2015-01-1710
Xinran Tao, Kan Zhou, Andrej Ivanco, John R. Wagner, Heath Hofmann, Zoran Filipi
ABSTRACT The components in a hybrid electric vehicle (HEV) powertrain include the battery pack, an internal combustion engine, and the electric machines such as motors and possibly a generator. These components generate a considerable amount of heat during driving cycles. A robust thermal management system with advanced controller, designed for temperature tracking, is required for vehicle safety and energy efficiency. This paper examines the integration of an advanced control algorithm to a HEV powertrain cooling system featuring an electric-mechanical compressor, coolant pump, three radiators, and heat exchanger and radiator fans. Mathematical models are developed to numerically describe the thermal behavior of these powertrain elements. A series of controllers are designed to effectively manage the battery pack, electric motors, and the internal combustion engine temperatures.
2015-04-14
Technical Paper
2015-01-0248
Hiroyasu Baba, Koji Kawasaki, Hideomi Kawachi
We have developed Li-ion battery heating system which is direct resistance heating for hybrid electric vehicles (HEV), plug-in hybrid vehicles (PHEV) and electric vehicles (EV) by use of an inverter and a motor. One relay is added between a positive terminal of Li-ion battery and one-phase (e.g. U-phase) of a three-phase motor. When additional relay is turned on, the motor coils, IGBTs (Insulated-gate bipolar transistor) in the inverter and a smoothing capacitor for the inverter constitute buck-boost DC to DC converter. IGBTs are controlled to repeat charging and discharging between the battery and the smoothing capacitor. We made a system prototype and examined battery heating capability. And also we optimized charging and discharging frequency from impedance and current to improve heat generation. This method can increase battery temperature from -20 deg C to -1 deg C in 5 minutes and can extend EV driving range. Additionally the system can be installed into all HEV, PHEV and EV.
2015-04-14
Technical Paper
2015-01-0747
Aimin Du, Zhongpan Zhu, Chuanchuan Chu, Mengmeng Li
The research on intake, injection and mixture formation process of some gasoline direct injection engine is studied by using the CFD simulation technique. The effects of spray hole layout and injection strategy on mixture quality is also analyzed. Results show that the mixture quality can be improved with appropriate orifice layout. Using two-stage injection under condition of full load at low speed, compared to one injection, the fuel quantity impinging to wall is reduced and the cylinder turbulent kinetic energy is increased. In addition, the concentration of mixture near the spark plug is increased, which is beneficial to ignition. With more appropriate injection timing and injection ratio, the quality of mixture will be better. During cold start processes, the wallfilm can be reduced with appropriate injection timing. During hot start processes, the quality of mixture is declined with later injection timing.
2015-04-14
Technical Paper
2015-01-1301
Naoki Yoneya, Masaru Yamasaki, Atsushi Yamanaka, Kentaro Mikawa, Hidefumi Iwaki, Isao Doi
Thermal calculation 1D simulator for electric Valve Timing Control system (VTC) was developed. As for automotive engine, performance improvement such as lower emission of CO2 is more required, by recent environment regulations. Variable valve trains are essential components, and VTC is one of them. VTC can change opening and closing timing of the intake and exhaust valves into the optimum timing, depending on the driving situation. Since conventional VTC is driven hydraulically, challenges are response speed and operation limit at low temperature. For quick response and expansion of operating conditions, electric VTC is being developed. Recently, quicker response of an electric VTC is required for more efficient combustion cycles like the Atkinson Cycle. Electric VTC consists of a motor, a reduction gear, and a controller.
2015-04-14
Technical Paper
2015-01-1752
Alex Melin, David Kittelson, William Northrop
In recent years, there has been growing interest in using alternative cycles to the standard Otto cycle in an effort to improve efficiency and lower emissions of spark-ignition engines. One such proposed concept is the 5-stroke engine. The 5-stroke uses two types of cylinders, a combustion cylinder and expansion cylinder with a transfer port between them. Excess pressure in the combustion cylinder can be further expanded by using a second expansion cylinder to harness additional work; a practical implementation of the Atkinson Cycle. Since the expansion cylinder runs on a two-stroke cycle, an additional increase in efficiency can result by connecting two combustion cylinders to one expansion cylinder in a three cylinder configuration. Although previous work has investigated the performance of prototype 5-stroke engines compared to1-D modeling results, none have conducted a thorough study on the interactions of various design parameters.
2015-04-14
Technical Paper
2015-01-0733
Nichole Verwys, Jesse Fritcher, Thomas DeMass
Dark, high gloss decorative finishes (i.e. piano black) are gaining increased applications and demands in vehicle interiors; due to interior stylists desire for this look . One significant concern with this trend is that scratches and other appearance-related defects such as orange peel (waviness) are more apparent to the customer. To address this issue, a highly scratch-resistant 2K clearcoat formulation was developed to minimize visible surface scratches, while also yielding minimal orange peel and exceptional DOI (distinctness of image); all while being applied using typical application techniques in the part finishing market. This output was accomplished by first bench-marking the consumer electronics market for appearance and scratch resistance, and then setting targets through that research.
2015-04-14
Technical Paper
2015-01-1394
Alessandro Naddeo, Marco Apicella, Davide Galluzzi
General comfort may be defined as the “level of well-being” perceived by humans in a working environment. The state-of-the-art about evaluation of comfort/discomfort shows the need for an objective method to evaluate the “effect in the internal body” and “perceived effects” in main systems of comfort perception. Some medical studies show that each human joint has its own natural Rest Posture (RP); in this Rest Posture human muscles are completely relaxed or at minimum strain level: when it happens the geometrical configuration corresponds to the natural position of resting Arms/Legs/Neck etc.. From this starting point, authors developed and build, through a wide experimental campaign, the postural-comfort curves for each DOF of human upper limbs joints; the obtained comfort curves are regular and don’t show any kind of discontinuity. A software named Ca-Man has been developed in order to analyze a general posture and calculate a postural comfort index for the entire upper body.
2015-04-14
Technical Paper
2015-01-1711
Christian Hainzlmaier, Alejandro S. Regueiro, Marvin Lappe
Hybrid- and Electric Vehicles have a heat deficit due to frequent operation of the engine in high efficiency regions or during pure electric driving where the engine as a heat source is not available. Especially for the conditioning of the cabin, additional heat sources are necessary to ensure comfort & safety. In order to maximize the electric driving range, and improve fuel efficiency, it is important to combine a fast, efficient and safe generation of heat, with a minimum drain from the traction battery. Webasto went about this challenge and developed the new Webasto High Voltage Heater (HVH) based on a new and patented heat layer technology. This paper explains the design concept and results of the novel clean sheet research and development approach taken to achieve the project goals.
2015-04-14
Technical Paper
2015-01-1692
Walter Ferraris, Fausto Di Sciullo, Carloandrea Malvicino, Francesco Vestrelli, Fabrizio Beltramelli, Giancarlo Gotta
Automotive world is rapidly changing driven by the incoming CO2 emission regulation and the need of decreased fuel consumption for every vehicle line. The introduction of high efficiency solutions in order to get fuel consumption reduction has been already done on many vehicle systems without forgetting the cost sustainability of such solutions and with a general trend of weight reduction. For what concerns cooling systems, the increased adoption of dual level cooling loops and water cooled charge air cooling is a clear trend. The present paper proposes a compact and cost effective solution with low temperature loop cooling water cooled charge air cooler and water cooled condenser for A and B segment vehicle, with the possibility to add other exchangers to the secondary loop. All the thermal load is managed by only one radiator.
2015-04-14
Technical Paper
2015-01-1712
Ram Vijayagopal, Aymeric Rousseau
This study looks at the impact of TEGs have on different types of light duty vehicles. UDDS, Highway and Combined 2 cycle procedures are used to evaluate the fuel economy benefits in these vehicles. These fuel economy benefits are then translated to gasoline savings and net present value of the monetary benefits. Previous studies had used TEG models that depend on exhaust flow traces recorded from the test bench. A better TEG model is developed which can estimate exhaust mass flow, and respond to variations in the exhaust flow. This model can also predict the temperature variations on the hot and cold side of the TEG modules. Better TEG modules are also modelled based on the published data from General Motors (GM). The heat dissipation through the TEG between the source and sink is modelled, but various other losses like contact losses or thermal losses within the TEG are not modelled.
2015-04-14
Technical Paper
2015-01-1472
Roberto Arienti, Carlo Cantoni, Massimiliano Gobbi, Giampiero Mastinu, Mario Pennati, Giorgio Previati
The lightweight seat of a high performance car is designed taking into account a rear impact. The basic parameters of the seat structure are derived resorting to the simulation of a crash test. A dummy is positioned on the seat and subject to a rear impulse. The simulations provide the dynamic loads acting on the seat structure, in particular the ones applied at the joint between the seat cushion and the seat backrest. Such a joint is simulated as a plastic hinge and dissipates some of the crash energy. By means of the simulations the proper parameters of the plastic hinge can be derived to design a safe seat. The simulations are validated by means of indoor tests with satisfactory results. By using the validated model, the influence of seat cushion and backrest parameters on seat passenger's injury are studied. An efficient tool has been developed for the preliminary design of lightweight seats for high performance cars.
2015-04-14
Technical Paper
2015-01-0327
Elizabeth M. Patterson, Iman Goldasteh, Salamah Maaita
Recent progress in computer-aided engineering (CAE) has made it possible to model complex interdisciplinary multiphysics analysis. This paper investigated the sequential coupled thermal-structural analysis by examining the associated thermal stresses under simulated operational conditions close to the real situation. An evaluation of exhaust muffler strain due to thermal stresses was made by coupling Star-CCM+ CFD software and ABAQUS structural analysis software. The study was made to evaluate discovered muffler durability test failure and to develop a countermeasure design to prevent future issues. Failure of the muffler internal pipe was discovered after heat cycle durability testing where the internal pipe had broken into two pieces. In the first step, CFD analysis was done by thermo-flow simulation in order to determine the resulting heat distribution on the muffler assembly when subjected to the prescribed peak duty cycle temperature.
2015-04-14
Technical Paper
2015-01-0335
Sandeep Makam, Christopher Dubbs, Yeliana Roosien, Feng Lin, William Resh
Due to ever-tightening CAFE regulations on passenger vehicles, it is necessary to find novel methods to improve powertrain system efficiency. These increases in efficiency must be cost effective so that the customer perceives that they add value. One approach for improving system efficiency has been the use of thermal energy management. For example, changing the flow of, or reusing “waste” heat from the powertrain to improve efficiency. Due to the interactions involved with thermal management, a system level approach is useful for exploring, selecting, and developing alternative solutions. It provides a structured approach to augment the right kind of synergies between subsystems and mitigate unintended consequences. However, one challenge with using these approaches early in a program is having appropriate metrics for assessing key aspects of the system behaviors.
2015-04-14
Journal Article
2015-01-1392
Se Jin Park, Seung Nam Min, Murali Subramaniyam, Heeran Lee, Yu Kyung Shin, Chang Hee Jang, Soon Hyun Hwang
Driving postures is essential for evaluation of a driver workspace and also for improved seat design comfort. Data on occupant posture and body dimensions is gathered widely using portable coordinate measurement equipment, optical motion capture equipment, infrared depth sensor, and posture monitoring system. Nowadays, a number of 3D scanners are available on the market, which mainly used to enable anthropometry in an entirely new way. This study captures the comfortable driving postures for Koreans using 3D scanning measuring techniques. Subjects consisted of twenty healthy individuals (10 males and 10 females) ranging in age from 20 to 40 years and were carefully selected to include in three different weight groups (> 59 kg, 60 ~ 79 kg and < 80 kg). Driving postures were captured using a handheld portable 3D scanner (model: Artec LTM). A total of 18 land markers were attached (car seat: 9 markers; subject: 9 markers).
2015-04-14
Journal Article
2015-01-0339
Aimon Allouache, Smith Leggett, Matthew J. Hall, Ming Tu, Chad Baker, Haiyan Fateh
The performance of an organic Rankine cycle (ORC) that recovers heat from the exhaust of a heavy-duty diesel engine was simulated. The work was an extension of a prior study that simulated the performance of an experimental ORC system developed and tested at Oak Ridge National laboratory (ORNL). The experimental data were used to set model parameters and validate the results of that simulation. For the current study the model was adapted to consider a 15 liter turbocharged engine versus the original 1.9 liter light-duty automotive turbodiesel studied by ORNL. Exhaust flow rate and temperature data for the heavy-duty engine were obtained from Southwest Research Institute (SwRI) for a range of steady-state engine speeds and loads without EGR. Because of the considerably higher exhaust gas flow rates of the heavy-duty engine, relative to the engine tested by ORNL, a different heat exchanger type was considered in order to keep exhaust pressure drop within practical bounds.
2015-04-14
Journal Article
2015-01-0326
Takuya Yamaguchi, Yuzo Aoyagi, Noboru Uchida, Akira Fukunaga, Masayuki Kobayashi, Takayuki Adachi, Munemasa Hashimoto
In heavy duty diesel engines, the waste heat recovery has attracted much attention as one of the technologies to improve fuel economy further. In this study, the available energy of the waste heat from a high boosted 6-cylinder heavy duty diesel engine which is equipped with a high pressure loop EGR system (HPL-EGR system) and low pressure loop EGR system (LPL-EGR system) was evaluated based on the second law of thermodynamics. The maximum potential of the waste heat recovery for improvement in brake thermal efficiency and the effect of the Rankine combined cycle on fuel economy were estimated for each single-stage turbocharging system (single-stage system) and 2-stage turbocharging system (2-stage system).
2015-04-14
Technical Paper
2015-01-0782
Philipp Huegel, Heiko Kubach, Thomas Koch, Amin Velji
Stratified operation with spray guided mixture preparation is a promising concept to reduce CO2 emissions from DI-SI Engines with Gasoline Direct Injection. The major reasons for the high efficiency at part load are the unthrottled operation of the engine and the high thermal efficiency because of the globally lean mixture. Another often named source for the high efficiency is the reduced wall heat transfer in spray guided stratified operation. In this work, heat loss was investigated in homogeneous and stratified DI-SI operation in the same single cylinder research engine. Several thermocouples were adapted to the combustion chamber surfaces. The crank angle resolved temperature oscillations of the cylinder head and piston surface were measured for homogeneous and stratified operation. A grashopper linkage was designed and adapted to the engine to transfer the piston signals to the data acquisition device. The design of the used experimental apparatus is described briefly.
2015-04-14
Journal Article
2015-01-0786
Keita Arato, Teruyuki Takashima
Recently, diesel engine has been researched and developed actively as a power source for not only heavy-duty vehicle but also passenger car. Improvement of fuel consumption is required in order to solve global warming issues and depletion of fossil oil resources. To improve brake thermal efficiency, improvement of indicate thermal efficiency and reduction of friction loss are essential. And to improve indicate thermal efficiency, it is important to improve theoretical thermal efficiency, combustion efficiency, and degree of constant volume. Reducing heat loss to the chamber wall is another factor for better thermal efficiency. In this study, a diesel engine with high compression ratio was of interest because of its higher theoretical thermal efficiency. Optimization of the combustion chamber shape was conducted by the three dimensional CFD simulation to reduce heat loss. Furthermore evaluation test using single cylinder engine was carried out.
2015-04-14
Journal Article
2015-01-1691
Manabu Matsumoto, Masayoshi Mori, Tomohide Haraguchi, Makoto Ohtani, Tomoya Kubo, Kanji Matsumoto, Hiroshi Matsuda
Exhaust heat recovery units that use a thermoelectric element generate electricity by creating a temperature difference in the thermoelectric element by heating one side and cooling the other side of the thermoelectric circuit (module). In this case, the typical structure does not directly join the thermoelectric module with the heat sink, and instead presses the thermoelectric module against the heat sink using bolts or other means in order to prevent thermoelectric element damage due to the difference in linear expansion between the cooled and heated sides of the thermoelectric module. However, this poses the issues associated with a complex, heavy and expensive structure. Therefore, a new vacuum space structure was devised that houses the thermoelectric module in a vacuum chamber and presses the module against the heat sink using atmospheric pressure.
2015-04-14
Technical Paper
2015-01-1189
Satyam Panchal, Scott Mathewson, Roydon Fraser, Richard Culham, Michael Fowler
A major challenge in the development of next generation electric and hybrid vehicle technology is the control and management of heat generation and operating temperatures. Vehicle performance, reliability and ultimately consumer market adoption are integrally dependent on successful battery thermal management designs. In addition to this, crucial to thermal modeling is accurate thermo-physical property input. Therefore, to design a thermal management system and for thermal modeling, a designer must study the thermal characteristics of batteries. This work presents a purely experimental thermal characterization of thermo-physical properties of a lithium-ion battery utilizing a promising electrode material, LiFePO4, in a prismatic pouch configuration. In this research, the thermal resistance and corresponding thermal conductivity of prismatic battery materials is evaluated.
Viewing 1 to 30 of 7577