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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 kilowatt (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 megawatt (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.
2015-04-14
Technical Paper
2015-01-1623
Ivan Arsie, Rocco Di Leo, Cesare Pianese, Matteo De Cesare
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 and 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
2015-01-1663
Prafulla P Ghare, Hemant Khalane, Udaysingh Wakhure, Tushar Khobragade, Sandip Chaudhari, Atul Jahirabadkar
As one of the most complicated parts of an internal combustion Engine, the cylinder head is directly exposed to high combustion pressures and temperatures. Cooling must be provided for the heated surfaces to avoid overheating. However over-cooling will cause problems such as lower overall efficiency and high emission. Therefore, an optimal design of the cooling system is required to maintain trouble-free operation of engine. For single cylinder naturally aspirated engines, designer has to package injector, valve guide bores, head bolt bosses and intake and exhaust valve ports in limited space. On account of these space restrictions, designing of cooling jacket is very critical. Engineers invest a large amount of time and serious effort to optimize the flow through engine cooling jacket. The complicated structure of a cylinder head leads to the difficulty in acquiring detailed information of conducting flow and heat transfer.
2015-04-14
Technical Paper
2015-01-1393
Misun Kwon, Sangdo Park, Chanho Jeong, Taehoon Lee, Sanghark LEE, Hoonbok Lee, Jinho Seo
In the era of diversification, car is not only a means of transportation, but also a place of leisure & refreshment. As more and more people drive cars, their demand is growing in a quality & quantity manner. Also industrial development facilitates a development of high class interiors in a car in and out of the world. And consumers prefer their convenience & comfort leading to an increase in demand for a premium car. Above all, car seat is a part where human body touches for the longest time, thereby having impact on consumes' preference for convenience & comfort. In this context, we designed a rear seat convenience system for premium car based on an assessment and comfort analysis according to consumers' tendency and character. Through this system, we aims to enhance the convenience & comfort of seat, and eventually improve passengers' satisfaction.
2015-04-14
Technical Paper
2015-01-0399
Alexander Jaust, Bastian Morcinkowski, Stefan Pischinger, Jens Ewald
In this work, a consistent transport and mixing model is derived and validated that calculates the same mixing in thermodynamic multi-zone space as in spacially resolved physical space. The transport and mixing model is developed using a turbulent channel flow as simplified domain. This physical domain of a direct numerical simulation (DNS) is divided into zones based on the quantitative value of transported scalars. Fluxes between the zones are introduced to describe mixing from the transport equation of the probability density function based on the mixing process in physical space. The mixing process of further scalars can then be carried out with these fluxes instead of solving additional transport equations. The relationship between the exchange flux in phase space and the concept of scalar dissipation are shown and validated by comparison to DNS results.
2015-04-14
Technical Paper
2015-01-0336
Amey Karnik, Daniel Pachner, Adrian M. Fuxman, David Germann, Mrdjan Jankovic, Christopher House
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 system is that the system operating conditions change continuously to meet the driver demand. 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. A solution to this problem is to design a control strategy that utilizes the estimate of variability of future disturbances.
2015-04-14
Technical Paper
2015-01-0348
Chuqi Su, Meng Xu, Naiqiang Tong, Yulian CHEN
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 temperature distribution of the heat exchanger. The simulation analysis shows that the thermoelectric modules (TMs) on different positions of the heat exchanger have different thermal performance, which can significantly influence the power generation efficiency of the system. Meanwhile, it is found that the thermal performance is affected by the clamping mechanism, which has a greater effect on the cold side than the hot side. Following the simulations, bench tests are carried out to confirm the reasonability of the simulation results.
2015-04-14
Technical Paper
2015-01-0339
Matthew J. Hall, Aimon Allouache, Smith Leggett, 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
Technical Paper
2015-01-0350
Jing Cai, Gangfeng Tan
Thermoelectric power generation could achieve the recovery of engine exhaust waste heat. For the conventional scheme, the hot-end of the thermoelectric module is connected with the exhaust pipe, while the cold-end is cooled through the engine cooling cycle. The variation of engine operating conditions brings the instability of the hot-end temperature, which affects the power generation performance of thermoelectric materials and increases the damage risk to the thermoelectric materials caused by the high temperature. This research adopts the heat transfer oil circulation as the intermediate fluid to absorb the dynamic heat flux of the engine exhaust so as to release the heat steadily to the hot-end of the thermoelectric module. The thermal characteristics of the target diesel engine exhaust gas are evaluated based on the experimental data firstly.
2015-04-14
Technical Paper
2015-01-0438
Ashley Lehman, Vesselin Stoilov, Andrzej Sobiesiak
This paper describes the application of the Fourier Amplitude Sensitivity Test (FAST) to investigate the thermal system performance of vehicle underbody components which are affected by variation in design parameters. The results from this study will pinpoint the design parameters which offer the greatest opportunity for improvement of thermal system performance and reliability. In turn, this method can save engineering time and resources. A mathematical model was first developed using Matlab for a vehicle underbody system consisting of a muffler, heat shield, and underbody panel. There were a number of input parameters identified. Some of these parameters deviate from their nominal value due to environmental factors, wear and ageing, or variation in the manufacturing process. These parameters include the emissivity of the muffler surface, the view factors between each component, and the temperature and velocity of the ambient air.
2015-04-14
Technical Paper
2015-01-0441
Takashi Takiguchi, Yasuhiro Takii, Yusuke Yano, Nobuyuki Ohta
We require fast and accurate prediction to know the thermal performance for each car package. We established a highly accurate full-vehicle thermal prediction method applying the identification coefficients that we get from vehicle test results. The primary method of predicting this is Computational Fluid Dynamics (CFD) of conjugate heat transfer. CFD predicts external and exhaust gas flow, including their temperatures. Conditions taken into consideration are vehicle speed and temperature, heat rejection rate of the condenser, radiator, fan rotation speed, and exhaust gas flow. There are three identification coefficients required by each process. 1) Water temperature prediction process: Calculate ENG cooling loss and solar load by the 1D model, and input it into CFD as a heat rejection rate of the radiator and condenser.
2015-04-14
Technical Paper
2015-01-0440
Julio Carrera, ALFREDO NAVARRO, Concepcion Paz, Alvaro SANCHEZ, Jacobo Porteiro
Recent emissions standards have become more restrictive in terms of CO2 and NOx reduction. This has been translated into higher EGR rates at higher exhaust gas temperatures with lower coolant flow rates for much longer lifetimes. In consequence, Thermal Load for EGR components, specially EGR coolers, has been increased and thermal fatigue durability is now a critical issue during the development. Consequently a new Thermo-Mechanical Analysis (TMA) procedure has been developed in order to calculate durability. The TMA calculation is based on a Computational Fluid Dynamics simulation (CFD) in which a boiling model is implemented for obtaining realistic temperature predictions of the metal parts exposed to possible local boiling. The FEM model has also been adjusted to capture the correct stress values by submodeling the critical areas. Life calculation is based on a Multiaxial Fatigue Model that has also been implemented in FEM software for node by node life calculation.
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
2015-01-0786
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
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
2015-01-0671
Saeed Jahangirian, Ashutosh srivastava, Seyed Hosseini, Steven Ballard, Naiqiang Wu, John Kiedaisch
Durability assessments of modern engines often require accurate modeling of thermal stresses in critical regions such as cylinder head firedecks under severe cyclic thermal loading conditions. A new methodology has been developed and experimentally validated in which transient temperature distributions on cylinder head, crankcase and other components are determined using a Conjugate Heat Transfer (CHT) CFD model and a thermal finite element analysis solution. In the first stage, cycle-averaged gas side boundary conditions are calculated from heat transfer modeling in a transient in-cylinder simulation. In the second stage, a steady-state CHT-CFD analysis of the full engine block is performed. Volume temperatures and surface heat transfer data are subsequently transferred to a thermal finite element model and steady state solutions are obtained which are validated against CFD and experimental results.
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
2015-01-1526
Yasuyuki Onishi, Thomas Ramsay, Timothy Juan, James McKillen
A sports car exhibits many challenges from an aerodynamic point of view: drag that limits top speed, lift - or down force - and balance that affects handling, brake cooling and insuring that the heat exchangers have enough air flowing through them under several vehicle speeds and ambient conditions. All of which must be balanced with a sports car styling and esthetic. Since this sports car will apply two electric motors to drive front axle and a high-rev V6 turbo charged engine in series with a 9-speed double-clutch transmission to drive rear axle, additional cooling was required, yielding a total of ten air cooled heat exchangers. It is also a challenge to introduce cooling air into the rear engine room to protect the car under severe thermal conditions.
2015-04-14
Technical Paper
2015-01-1709
Daniel Leighton
Electric drive vehicles (EDVs) have complex thermal management requirements not present in traditional internal combustion engine vehicles. In addition to cabin conditioning, the battery, power electronics, and electric motor drivetrain sub-systems also require thermal management. Many current generation EDVs utilize separate cooling systems for each of these sub-systems, which adds both weight and cost. Another issue for EDVs is the lack of abundant waste heat from the engine for cabin heating. In many cases EDVs use battery energy to heat the cabin via an electrical resistance heater, which results in vehicle range reductions of nearly 50% under cold ambient conditions. These EDV thermal challenges present an opportunity for integrated vehicle thermal management technologies which can reduce cost and weight, and enable efficient heating methods that increase vehicle range.
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.
2015-01-30
Article
New approach to HVAC case design incorporates an optimized center section and side sections that can be shaped and sized for specific performance and packaging. Blower fan remains in separate case and a dual-fan design is available for more precise airflow management between outside air and recirculating air.
2015-01-23
Article
At the 2015 North American International Auto Show, the company showed a conceptual diorama and illustrations of its Smart City developments and offered visitors a "ride" in its V2X simulator.
2015-01-23
Article
Demonstrated at the 2015 North American International Auto Show in Detroit, the new infotainment solution has more-responsive capacitive touch screen, upgraded voice recognition, and new apps.
2015-01-14
Article
More than 30 innovations ranging from production-ready to exploratory are featured in a luxury-oriented concept interior aimed at autonomous vehicles.
2015-01-14
Technical Paper
2015-26-0045
Rico Baumgart, Joerg Aurich, Jan Ackermann, Christoph Danzer
Abstract The development of energy efficient air conditioning systems for electric vehicles is an ever increasing challenge, because the cooling as well as the heating of the passenger compartment reduces the cruising range dramatically. Electric cars are usually equipped with a scroll compressor and a separate electric motor with appropriate power electronics. However, this solution is critical in terms of the installation space, the weight and also the costs. Therefore, an innovative and energy efficient drivetrain structure for electric vehicles was developed, which integrates the motor of the A/C-compressor directly into the drivetrain. Thus it is possible to switch off the compressor motor and to use the main motor for the drive of the compressor at certain driving situations. As a result, the operating point of the main motor can be shifted to a better efficiency.
2015-01-14
Technical Paper
2015-26-0043
Rajesh Kashyap, Vamsidhar Sunkari, Prakash Verma
Abstract Regular service of the vehicle is to be done with high precision service equipment, to ensure the factory performance of the vehicle over the entire life of product usage. However, complex nature of the physical processes involved in the service of the vehicle subsystems makes it costly for optimizing the service equipment performance for entire range of operation. Air-conditioning service (ACS) equipment is one such product in the diagnostics domain which deals with compressible, transient and two phase flow in open loop systems. Development of control system for the service equipment to perform optimally over the entire operational range requires accurate mathematical model of the system under study. Application of mathematical model based approach requires calculation of geometrical details, environment information and fluid properties during the process for estimating the process behavior.
2015-01-14
Technical Paper
2015-26-0044
Sambhaji Keshaw Jaybhay, Prasanna Nagarhalli, Suresh Tadigadapa, Sangeet Hari Kapoor
Abstract This paper focuses on factors that enhance energy efficiency of air conditioning system on mid-sized, standard and premium buses with engine power from 125 to 280 HP. It covers aspects like light weighting of roof air conditioning system, usage of optimized ducting system with minimal resistance to blowers, deployment of rotary scroll compressor with fast idle control in place of reciprocating piston compressor. The scope of this paper covers AC compressors driven by main engine of vehicle/ bus, study related to auxiliary/donkey engine driven AC compressor is not considered. Context- In order to enhance fuel efficiency in buses an energy efficient air conditioning system should be deployed. This will lead to reduced parasitic load on the engine and translate into direct fuel saving.
2015-01-14
Technical Paper
2015-26-0052
Ashish Jashvantlal Modi, Dhiren Patel
Abstract The main focus areas of today's IC engine design are energy efficiency and higher thermal efficiency. As there is a high amount of heat loss in atmosphere due to which the efficiency is lower for the standard engine. There is one possible solution to reduce such problem i.e., converting the conventional CI engine in to the LHR engine. For the current work the performance and emission characteristics are evaluated for the twin cylinder ceramic coated water cooled CI engine using blends of diesel and neem bio diesel. For the present work the bio-diesel was prepared in laboratory from non-edible vegetable oil (neem oil) by transesterification process with methanol, where potassium hydroxide (KOH) was used as a catalyst. Combustion chamber inner wall, Piston top surface (crown) and valve faces were coated with the Magnesium Zirconate (MgZrO3).
2015-01-14
Journal Article
2015-26-0136
Deepak Mahajan, Arnab Sandilya, Lokesh Khandelwal, Sameer Srivastava
Abstract Automotive floor carpet serves the purpose of insulating airborne noises like road-tire noise, transmission noise, fuel pump noise etc. Most commonly used automotive floor carpet structure is- molded sound barrier (PE, vinyl etc.) decoupled from the floor pan with an absorber such as felt. With increasing customer expectations and fuel efficiency requirements, the NVH requirements are increasing as well. The only possible way of increasing acoustic performance (Specifically, Sound Transmission Loss, STL) in the mentioned carpet structure is to increase the barrier material. This solution, however, comes at a great weight penalty. Theoretically, increasing the number of decoupled barrier layers greatly enhances the STL performance of an acoustic packaging for same weight. In practice, however, this solution presents problems like- ineffectiveness at lower frequencies, sudden dip in performance at modal frequencies.
2015-01-14
Technical Paper
2015-26-0140
Milind Ambardekar, Adatiya Yogesh, Sudhakara Naidu
Abstract Production variations of a heavy duty truck for its vibrations were measured and then analyzed through an Ishikawa diagram. Noise and Control factors of the truck idle shake were indentified. The major cause was found to be piece to piece variations of its power-train (PT) rubber mounts. To overcome the same, a new nominal level of the mount stiffness was sought based on minimization of a cost function related to vibration transmissibility and fatigue damage of the mounts under dynamic loadings. Physical prototypes of such mounts were proved to minimize the variations of the driver's seat shake at idling among various trucks of the same design. These learning's are useful for design of various subsystems or components to refine the full vehicle-Noise Vibration Harshness (NVH) at the robust design level.
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