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2015-04-14
Technical Paper
2015-01-1189
Satyam Panchal, Scott Mathewson, Roydon Fraser, Richard Culham, Michael Fowler
Abstract A major challenge in the development of the next generation electric and hybrid electric vehicle (EV and HEV) 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.
2015-04-14
Technical Paper
2015-01-1334
Shreyas Shingavi, Pankaj Bhirud, Abhishek Ranjan
Abstract Safety and Comfort are the core requirements of the automotive seating systems. Number of the occupants, determines type of the seating system requirement. The second row seat often needs to fold and slide, to allow the passenger to enter inside the car. Folding second row seat will also allow accommodating larger length cargo. The over folding of seat is controlled by hard stop mechanism. The hard stop mechanism generally consists of the seat arm stopper at back seat and hard stop located at base of the seat. These stoppers will limit the further motion of back seat. The folding speed of back seat is governed by various factors e.g. adjacent seat foam/structure friction, location, structural mass of seat etc. The scope of the paper is to evaluate various folding speeds of the back seat. Its effects are evaluated for the stresses and fatigue life of the hard stop components.
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
Abstract Pressure and temperature levels within a modern internal combustion engine cylinder have been pushing to 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 densities. Thus, 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
2015-01-0613
Donghong Ning, James Coyte, Hai Huang, Haiping Du, Weihua Li
Abstract This paper presents a study on experimental vibration simulation using a multiple-DOF motion platform for heavy duty vehicle seat suspension test. The platform is designed to have 6-DOF with the advantages of high force-to-weight ratio, high dexterity and high position accuracy. It can simulate vehicle vibrations in the x, y and z translational axis and in the roll pitch and yaw axis rotation. To use this platform to emulate the real vibration measured from vehicle seat base under real operation for vehicle seat suspension test in lab, an Inertial Measurement Unit (IMU) is applied to collect the acceleration data from a real vehicle. An estimation algorithm is developed to estimate the displacement from the measured acceleration. The estimated displacement is then used to calculate the length of each leg of the platform so that the platform can generate the motion similar to the measured one.
2015-04-14
Technical Paper
2015-01-1394
Alessandro Naddeo, Marco Apicella, Davide Galluzzi
Abstract General comfort can be defined as the measure of the “level of wellbeing” perceived by humans when interacting with a working environment. The state of the art for comfort/discomfort evaluation shows the need for an objective method to evaluate both “effects on the internal body” and “perceived effects” when considering the perception of comfort. Medical studies show that each joint has its own natural resting posture. In this posture, our muscles are completely relaxed or at minimum levels of strain. The body's geometrical configuration corresponds to the natural resting position of arms/legs/neck etc. From this starting point, the authors experimented to develop and built postural-comfort curves for each degree of freedom (DOF) of upper-limb joints. These curves are regular, and do not show any kind of discontinuity. Software (CA-Man®) was developed to analyze different postures and calculate a postural comfort index for the entire upper body.
2015-04-14
Technical Paper
2015-01-1713
Manfred Klaus Kirschning, Frank Reußwig
Abstract Different heat shielding unilayer materials already in practical use and multilayer materials, consisting of a compound of E-glass fabric laminated with aluminum foil and different high temperature felts, are compared with regards to the difference between the external and internal surface temperature ΔT as a function of the external surface temperature. Beside that the general difference between the two standard methods convection heat measurement and radiant heat measurement is shown. Especially it is evaluated whether the radiant heat measurement method is suitable to make a general statement for classification of heat shielding materials.
2015-04-14
Technical Paper
2015-01-1623
Ivan Arsie, Rocco Di Leo, Stefano Falco, Cesare Pianese, Matteo De Cesare
Abstract International regulations continuously restrict the standards for the exhaust emissions from automotive engines. In order to comply with these requirements, innovative control and diagnosis systems are needed. In this scenario the application of methodologies based on the in-cylinder pressure measurement finds widespread applications. Indeed, almost all engine thermodynamic variables useful for either control or diagnosis can be derived from the in-cylinder pressure. Apart for improving the control accuracy, the availability of the in-cylinder pressure signal might also allow reducing the number of existing sensors on-board, thus lowering the equipment costs and the engine wiring complexity. The paper focuses on the detection of the engine thermal state, which is fundamental to achieve suitable control of engine combustion and after-treatment devices.
2015-04-14
Technical Paper
2015-01-1610
Xiaomeng Shen, Gangfeng Tan, Quan Zhou, Zhongjie Yang, Min Hua
Abstract The Organic Rankine Cycle System is an effective approach for recovering the engine exhaust thermal energy. The physical characteristic of the Rankine fluid is the key factor for the capacity and the stability of the expander power output. In the research, the influences of the evaporator organic medium state and flow rate on the expander power output are fully analyzed for the sufficient utilization of the waste thermal energy. Firstly, the exhaust characteristics of the diesel engine were processed by the data of the bench test. Then, the integral mathematical model of the Organic Rankine Cycle was built. Based on the comparison for the 2-zone and 3-zone evaporator, the influence for expander output are analyzed especially emphasis on the factors of engine working condition, the flow rate, temperature and state of Rankine fluid.
2015-04-14
Technical Paper
2015-01-1608
Davide Di Battista, Marco Mauriello, Roberto Cipollone
Abstract A smart way to reduce CO2 emission in transportation sector is to recover energy usually wasted and re-use it for engine and vehicle needs. ORC plant on exhaust gas of ICE is really interesting, but it has a significant impact on the exhaust line and vehicle's weight. The backpressure realized in the exhaust and the weight gain, in fact, produce a specific fuel consumption increase as well as an increase in the propulsion power: both terms could vanish the energy recovered. The paper discusses the effects of the pressure losses produced by an ORC plant mounted on the exhaust line of an IVECO F1C test bench engine. The interactions produced on the turbocharged engine have been experimentally investigated: the presence of an IGV turbocharger makes the effect of the backpressure not straightforward to be predicted and needed a full experimental testing of the group in order to understand its reaction and the net effect in terms of specific fuel consumption.
2015-04-14
Technical Paper
2015-01-1609
Roberto Monforte, Francesco Lovuolo, Matteo Rostagno, Riccardo Seccardini, Teron Matton
Abstract Following the development of new technologies in Vehicle Thermal Management aiming to both enhancing the MAC System efficiency and reducing the thermal load to be managed, a prediction tool based on the AMEsim platform was developed at Advanced PD EMEA. This tool is dedicated to predict the effect of the implementation of sensors monitoring both the relative humidity and the carbon dioxide (CO2) concentration (taking into account passengers' generated moisture and CO2). This model implemented with the usual comfort inputs (CO2 and RH acceptable ranges) considers the system variables influencing the comfort and predicts the increase of both RH and CO2 concentration in the cabin compartment in any driving cycle depending on the number of occupants.
2015-04-14
Technical Paper
2015-01-1607
Chuen-Sen Lin, Vamshi Avadhanula, Vamsi Mokkapati, Daisy Huang, Brent Sheets
This paper presents test results of a 50 kW Organic Rankine Cycle (ORC) system and proposed guidelines for how to effectively apply this system to the rural Alaska power industry. In rural Alaska, approximately 180 villages rely on off-grid diesel generators for power. Most of the generators have capacities of about 1 MW or less. In general, the average operation efficiencies are noticeably less than 40%, with the rest of the fuel energy becoming heat. If the heat is not applied for useful application, it is called waste heat. Most of the wasted heat is contained in engine exhaust and jacket fluid and eventually dissipates into the environment. For rural Alaska, waste heat for heating is most effective; in many cases, waste heat for power may be needed due to a variety of reasons. Many rural Alaskan villages are reluctant to apply exhaust heat recovery due to concerns about corrosion and soot accumulation in the exhaust system and their effect on emissions.
2015-04-14
Technical Paper
2015-01-0169
Kazuyuki Nakata, Maya Seki, Ryoichi Nishikawa, Soju Matsumoto, Shinichiro Murakami, Yukio Yoshino
Abstract Instrument clusters that display all information on a TFT-LCD screen, also known as reconfigurable instrument clusters, have become the new trend in automotive interiors. DENSO mass-produced the world's first reconfigurable instrument cluster in 2008. To satisfy customer requirements, large quantities of resources were required. Coupled with an iterative process due to requirement changes, development costs became very high. Reducing development costs was vital in order to expand the reconfigurable instrument cluster product line. A new artist-centric HMI (human machine interface) software development workflow is proposed to reduce the development effort by introducing a data converter and real-time 3D rendering engine in our earlier paper. Our goal is to realize an environment with little programming during development by utilizing a tool chain to automate the majority of the programmer's tasks.
2015-04-14
Technical Paper
2015-01-0248
Hiroyasu Baba, Koji Kawasaki, Hideomi Kawachi
Abstract 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) and diodes 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 degrees C to 0 degrees C in 5 minutes and can extend EV driving range.
2015-04-14
Technical Paper
2015-01-0344
Yingchao Zhang, Weijiang Meng, Tao Chen, Yong Hao, Wei Ding
Abstract It is known that the automobile cabin thermal comfort, could keep the driver and passengers feel better which has a great effect on traffic safety. In this paper, to the FAW truck cab, we did some researches about automobile cabin thermal comfort. Our plan is to calculate the air flow distribution and the temperature in steady and transient state when there is warm or cool air flow. The heating and cooling experiment methods standard of cabin are based on the national standard and the automobile industry standard of China. Then the numerical simulation process becomes very important. So we used the commercial CFD code- STAR-CCM+ for study in this paper. Firstly, Geometry Clean up. Secondly, Wrap and Remesh, we chose the internal surface at the wrap surface of cabin and air conditioning pipes, then we remesh the surface. Thirdly, generate the volume mesh which is polyhedral mesh, and the number of the volume mesh is 9.4 millions.
2015-04-14
Technical Paper
2015-01-0341
Georg Rauch, Johannes Lutz, Martin Werner, Sagar Gurwara, Peter Steinberg
Abstract This paper introduces an innovative approach, named synergetic 1D-3D-Coupling, by using synergy effects of 1D and 3D simulation in order to bring down modeling and simulation efforts. At the same time the methodology sustains the spatial resolution of a 3D model. This goal is reached by reducing the 3D fluid side with its time consuming continuity, momentum, energy and turbulence equations to a simple but precise 1D model. Because of the solid structure staying three dimensional, heat flux direction and spatial resolution have 3D accuracy but short calculation times due to the simple heat diffusion equation to be solved. The 1D model is represented by an automatically generated equation system which is capable of considering transient effects. The energy transfer between 1D fluid model and 3D structure model is realized through a neutral 1D-3D-coupling program and the application of the fluid element specific Nusselt correlations.
2015-04-14
Technical Paper
2015-01-0349
Suvankar Manna, Yogendra Singh Kushwah
With stringent requirements of fuel efficiency and emissions, the airflow and thermal management within the under-hood environment is gaining significance day by day. While adequate airflow is required for cooling requirements under various vehicle operating conditions, it is also necessary to optimize it for reduced cooling drag and fan power. Hence, the need of the day is to maximize cooling requirements of Condenser, Radiator, CAC and other heat exchangers with minimal power consumption. To achieve this objective and due to the complicated nature of 3D flow phenomenon within the under-hood environment, it is useful to perform 3D CFD studies during preliminary stages to shorten design time and improve the quality and reliability of product design. In this paper we present the results from a CFD under-hood analysis that was carried out for design, development and optimization of a CRFM (Condenser, Radiator and Fan Module).
2015-04-14
Technical Paper
2015-01-0348
Chuqi Su, Meng Xu, Naiqiang Tong, Yulian Chen
Abstract The potential for automotive exhaust-based thermoelectric generator (TEG) has been increasing with continuously advances in thermoelectric technology. In this paper, the thermal deformation of the TEG system is studied on the basis of the surface temperature distribution of the heat exchanger. The simulation result shows that thermoelectric modules (TMs) on different positions have different thermal performance which can significantly influence the power generation efficiency of the system. Meanwhile, in terms of the working performance of TMs, the clamping mechanism is considered to have some effects on both the cold side and the hot side of TEG. Following the simulation, bench tests are carried out to confirm the reasonability of the simulation results.
2015-04-14
Technical Paper
2015-01-0347
Logesh Shankar Somasundaram, S Sriraman, Rakesh Verma
The paper aims at numerically modeling the flow and thermal processes occurring in an agricultural tractor using Computational Fluid Dynamics (CFD) and determines the comfort level of the tractor operator during working condition. The motive of the investigation is to develop and demonstrate capabilities of CFD as an automotive analysis tool. The work describes a methodology that significantly stream lines the process of thermal flow taking place in a tractor by utilizing state-of-the art computer simulation of air flow and heat transfer. The numerical investigation carried out with a three-dimensional geometry of the vehicle assembly and the measurements were taken from the vehicle. The geometry created with Pro/Engineer formed the domain for the automatically generating discretized grid contained the majority of the main components within the underhood environment.
2015-04-14
Technical Paper
2015-01-0346
Lei Dongxu, Minli Bai, Jizu Lv, Peng Wang, Chengzhi Hu, Yuyan Wang
Abstract Due to the latent heat of vaporization, the efficiency of boiling heat transfer is several times and even dozens of times higher than that of the convection heat transfer. With the improvement of power density of the engine, there are more requirements for engine cooling system design. It has been confirmed that the subcooled boiling did exist in the engine cooling. If boiling heat transfer can be reasonablely used, we can achieve the objective of enhancing heat transfer without changing the existing structure. In this paper, in order to quantitatively research the subcooled boiling in the engine, we simulated the subcooled boiling in the analog channel with the Euler multiphase model, found the importance of the turbulent dispersion. In additon, we explored the applicability of existing models to subcooled boiling, and compared the results with the experiment.
2015-04-14
Technical Paper
2015-01-0327
Elizabeth M. Patterson, Iman Goldasteh, Salamah Maaita
Abstract Recent progress in computer-aided engineering (CAE) has made it possible to model complex interdisciplinary multiphysics analyses. 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 FEM structural analysis software. The study was made to evaluate discovered muffler durability test failure and to develop a countermeasure design. Failure of the muffler internal pipe was discovered after heat cycle durability testing. The internal pipe had broken into two pieces. In the first step, CFD analysis was done by thermo-flow simulation to determine the resulting heat distribution on the muffler assembly when subjected to the prescribed peak duty cycle temperature.
2015-04-14
Technical Paper
2015-01-0328
Wilko Jansen, Joe Amodeo, Sam Wakelam, Kamalesh Bhambare
Abstract The level of infotainment in today's vehicles and the customer expectation of the functionality imply a significant effort is required on thermal management of the systems, to guarantee their full operation under all operating conditions. The worst case thermal conditions the system will get exposed to are caused by solar loading on the cabin or heat up as a result of cabin heating. Simulation of a solar load driven case will be discussed in this paper. The long soak conditions during these tests result in the modelling requirement for long natural convection periods. This is creating a challenge for the conventional CFD simulations in turnaround time. New simulation methodology has resulted in significant speed up enabling these fully transient simulations in a reasonable turnaround time to enable programme support. A two phase approach to simulating this problem is proposed in this paper.
2015-04-14
Technical Paper
2015-01-0331
Sina Shojaei, Simon Robinson, Chris Chatham, Andrew McGordon, James Marco
Abstract Among the auxiliary systems on electric and hybrid electric vehicles the electric air conditioning (eAC) system causes the largest load on the high voltage battery and can significantly impact the energy efficiency and performance of the vehicle. New methods are being investigated for effective management of air conditioning loads through their integration into vehicle level energy management strategies. For this purpose, a fully integrated vehicle model is developed for a commercially available hybrid vehicle and used to develop energy management algorithms. In this paper, details of the eAC model of this vehicle are discussed, including steady state component validation against rig data. Also results of simulating the cabin pull-down are included.
2015-04-14
Technical Paper
2015-01-0330
Iman Goldasteh, Shi-Ing Chang, Salamah Maaita, Gursaran Mathur
Abstract Proper flow distribution on the windshield and side windows is critical for adequate visibility while driving. Fog or ice which forms on the windshield is the main reason of invisibility and leads to major safety issue. It has been shown that proper clear visibility for the windshield could be obtained with a better flow pattern and uniform flow distribution in the defrost mode of the automobile heating, ventilation, and air-conditioning (HVAC) system. In this study, a three dimensional numerical model of a car cabin with full HVAC system was developed using Star-CCM+, a commercial CFD package. The Reynolds-Averaged Navier-Stokes equations (RANS) approach with the realizable two-layer k-ε turbulence model was employed for simulating the airflow field on the windshield for the defrost mode. The HVAC unit, ducts and defroster grille were included in the analysis in detail and the air distribution on the windshield was studied.
2015-04-14
Technical Paper
2015-01-0340
Jan Eller, Thomas Binner, Heinrich Reister, Nils Widdecke, Jochen Wiedemann
Abstract Collective life-cycle data is needed when developing components like elastomer suspension mounts. Life-time prediction is only possible using thermal load frequency distributions. In addition to current extreme load cases, the Idle Load Case is examined at Mercedes-Benz Car Group as a collective load case for Vehicle Thermal Management (VTM) numerical simulations in early development stages. It combines validation opportunities for HVAC, cooling and transmission requirements in hot-country-type ambient conditions. Experiments in climatic wind tunnels and coupled 3D CFD and heat transfer simulations of the Idle Load Case have been performed. Measurements show steady conditions at the end of the load case. Decoupling of the torque converter, changes in ambient temperature and the technical implementation of a wind barrier for still air conditions exhibit influence on component-level results. Solar load, however, does not significantly change the examined component temperatures.
2015-04-14
Technical Paper
2015-01-0336
Amey Karnik, Daniel Pachner, Adrian M. Fuxman, David Germann, Mrdjan Jankovic, Christopher House
Abstract Numerous studies describe the fuel consumption benefits of changing the powertrain temperature based on vehicle operating conditions. Actuators such as electric water pumps and active thermostats now provide more flexibility to change powertrain operating temperature than traditional mechanical-only systems did. Various control strategies have been proposed for powertrain temperature set-point regulation. A characteristic of powertrain thermal management systems is that the operating conditions (speed, load etc) change continuously to meet the driver demand and in most cases, the optimal conditions lie on the edge of the constraint envelope. Control strategies for set-point regulation which rely purely on feedback for disturbance rejection, without knowledge of future disturbances, might not provide the full fuel consumption benefits due to the slow thermal inertia of the system.
2015-04-14
Technical Paper
2015-01-0362
Neal Lawrence, Stefan Elbel
Abstract Much attention has been given in recent years to the use of two-phase ejectors and particularly to the performance of the standard ejector cycle with a liquid-vapor separator. However, this cycle may not be the best choice for automotive applications due to the large size required by an efficient separator as well as the cycle's performance at conditions of lower ejector potential. A limited amount of recent research has focused on alternate two-phase ejector cycles that may be better suited for automotive applications. One of these cycles, using the ejector to allow for evaporation at two different temperatures and eliminating the need for a separator, will be the subject of investigation in this paper. Previous investigations of this cycle have been mainly theoretical or experimental; this paper aims to provide a numerical analysis of the effect of evaporator design on the performance of the ejector cycles.
2015-04-14
Technical Paper
2015-01-0363
Vasanth Balashunmuganathan, Ramakrishna Nukala, Sathishkumar Sampath Kumar, Murali Govindarajalu
In recent years clearing the mist on side windows is one of the main criterions for all OEMs for providing comfort level to the person while driving. Visibility through the side windows will be poor when the mist is not cleared to the desired level. “Windows fog up excessively/don't clear quickly” is one of the JD Power question to assess the customer satisfaction related to HVAC performance. In a Mobile Air Conditioning System, HVAC demister duct and outlet plays an important role for removing the mist formation on vehicle side window. Normally demister duct and outlet design is evaluated by the target airflow and velocity achieved at driver and passenger side window. The methodology for optimizing the demister outlet located at side door trim has been discussed. Detailed studies are carried out for creating a parametric modeling and optimization of demister outlet design for meeting the target velocity.
2015-04-14
Technical Paper
2015-01-0365
Gursaran D. Mathur
Abstract Experimental studies have been conducted to determine the energy stored in vehicle's Cockpit Module (CPM) at cold soaking conditions for a MY2012 production vehicle. Detailed analysis has been done in this paper to show the influence of energy stored in various components (e.g., Instrument panel, HVAC system, heat exchanger, wire harness, etc.) contained within the CPM unit. Experiments conducted show that the instrument panel stores the maximum amount of energy at a given temperature.
2015-04-14
Technical Paper
2015-01-0366
Cristian Rostiti, Stephanie Stockar, Marcello Canova
Abstract In a conventional passenger vehicle, the AC system is the largest ancillary load. This paper proposes a novel control strategy to reduce the energy consumption of the air conditioning system of a conventional passenger car. The problem of reducing the parasitic load of the AC system is first approached as a multi-objective optimization problem. Starting from a validated control-oriented model of an automotive AC system, an optimization problem is formalized to achieve the best possible fuel economy over a regulatory driving cycle, while guaranteeing the passenger comfort in terms of cabin temperature and reduce the wear of the components. To complete the formulation of the problem, a set of constraints on the pressure in the heat exchanger are defined to guarantee the safe operation of the system. The Dynamic Programming (DP), a numerical optimization technique, is then used to obtain the optimal solution in form of a control sequence over a prescribed driving cycle.
2015-04-14
Technical Paper
2015-01-0368
Janampally Sandeep Kumar Reddy, Shailendra Deopa, Abhay Sharma, Piyush Aggarwal
Abstract Bumper opening area projected on condenser to total condenser core area is referred to as condenser opening area. The condenser opening area plays a vital role in A/C Performance of vehicle particularly during idling and initial cooling of vehicle. This paper presents detail study on effects of condenser opening area on A/C performance. Based on theory, the effect of condenser opening area is studied and it is validated by experimental results. Depending on these results an optimum value of condenser opening area required for best A/C performance is concluded.
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