Criteria

Text:
Display:

Results

Viewing 1 to 30 of 282
2017-10-08
Technical Paper
2017-01-2229
Byeongsoek Lee, Heechang Oh, SeungKook Han, SooHyung Woo, JinWook Son
There are two way to improve engine thermal efficiency. One is to improve the theoretical thermal efficiency by increasing the compression ratio and specific heat ratio. The other is to reduce various engine losses like friction, pumping, heat loss. For the development of Ultra High Efficiency, We designed the new 2.0L NA GDI engine based on HMC's Nu 2.0L GDI engine. We conducted various parameter studies related to gasoline combustion characteristic, such as compression ratio, ignition system, intake port design, cam duration, Cooled EGR, etc. As a result, we achieved the maximum thermal efficiency up to 42%(~200g/kWh) in stoichiometric AFR. This paper described the ways and possibilities to improve the maximum thermal efficiency.
2017-10-08
Technical Paper
2017-01-2204
Hoon Lee, Kwangwoo Jeong, Sanghoon Yoo, Byungho Lee, Sejun Kim
Hyundai Motor Company recently developed a multi-way, electrical coolant valve for engine thermal management module. The main purposes of the system that replaces a mechanical thermostat are to boost fuel economy by accelerating warm-up and to enhance thermal efficiency by actively controlling engine operating temperature. The electrical valve controls the amount of coolant flow to components such as oil heat exchanger, heater core, and radiator, while providing separate cooling for engine block and head. The coolant flow is modulated by varying the valve angle actuated with an electric motor. The system operates under a thermal management strategy that consists of multiple phases including zero coolant flow mode, and for those phases that require coolant temperature control, a feedback algorithm is designed for the flow control.
2017-09-19
Technical Paper
2017-01-2037
Daniel Schlabe, Dirk Zimmer, Alexander Pollok
The thermal inertia of aircraft cabins and galleys is significant for commercial aircraft. The aircraft cabin is controlled by the Environment Control System (ECS) to reach, among other targets, a prescribed temperature. Allowing a temperature band of e.g. 2 K around the prescribed temperature, it is possible to use the cabin dynamics as an energy storage. This storage can then be used to reduce electrical peak power, increase efficiency of ECS, reduce thermal cooling peak power, or reduce engine offtake if it is costly or not sufficiently available. In the same way, also the aircraft galleys can be exploited. Since ECS and galleys are among the largest consumers of electrical power or bleed air, there is a large potential on improving energy efficiency or reducing system mass to reduce fuel consumption of aircraft. This paper investigates different exploitation strategies of cabin and galley dynamics using modelling and simulation.
2017-09-19
Technical Paper
2017-01-2038
Russell H. Strehlow
Abstract A Vapor Envelope is an ultra-thin-walled vapor chamber that enables a unique combination of lighter weight, lower profile, and lower cost for heat spreading or heat removal applications. It evolved from work done as part of a DARPA program on Thermal Ground Planes. This paper examines a published testing protocol for the measurement of the thermal resistance of thin flexible thermal ground planes. It then applies an adapted version of the published technique to measure the thermal resistance of a vapor envelope and a dimensionally equivalent solid copper heat spreader. Finally, it looks at the implications of a significantly lower thermal resistance for a specific configuration. The analysis of whether this adapted technique would provide a sufficient metric for industrial application identified the control and understanding of the thermal interface materials as a key determinate.
2017-09-19
Technical Paper
2017-01-2039
Michael Sielemann, Changsoo Lee, Victor-Marie LeBrun, Chiwoo Ahn, Arnaud Colleoni, Dongkyu Lee, JeongSeok Lee, Anh Nguyen, Katrin Proelss, Hyon Min Yoon
Abstract Thermal management on aircraft has been an important discipline for several decades. However, with the recent generations of high performance aircraft, thermal management has evolved more and more into a critical performance and capability constraint on the whole aircraft level. Fuel continues to be the most important heat sink on high performance aircraft, and consequently the requirements on thermal models of fuel systems are expanding. As the scope of modeling and simulation is widened in general, it is not meaningful to introduce a new isolated modeling and simulation capability. Instead, thermal models must be derived from existing model assets and eventually enable integration across several physical domains. This paper describes such an integrated approach based on the Modelica Fuel System Library and the 3DExperience Platform.
2017-09-04
Technical Paper
2017-24-0158
Teresa Castiglione, Giuseppe Franzè, Angelo Algieri, Pietropaolo Morrone, Sergio Bova
Abstract In this paper, we propose a novel control architecture for dealing with the requirements arising in a cooling system of an ICE. The idea is to take advantage of the joint action of an electric pump and of an ad-hoc regulation module, which is used to determine adequate flow rates despite engine speeds. Specifically, a robust Model Predictive Control approach is exploited to take care formally of input/output constraints and disturbance effects of the resulting lumped parameter model of the engine cooling system, which incorporates the nucleate boiling heat transfer regime. Numerical simulations and test rig experimental data are presented. The results achieved show that the proposed control scheme is capable of providing effective and safe cooling while mitigating disturbance effects and minimizing coolant flow rates when compared with the action pertaining to standard crankshaft driven pumps.
2017-09-04
Journal Article
2017-24-0021
Sabino Caputo, Federico Millo, Giancarlo Cifali, Francesco Concetto Pesce
Abstract One of the key technologies for the improvement of the diesel engine thermal efficiency is the reduction of the engine heat transfer through the thermal insulation of the combustion chamber. This paper presents a numerical investigation on the effects of the combustion chamber insulation on the heat transfer, thermal efficiency and exhaust temperatures of a 1.6 l passenger car, turbo-charged diesel engine. First, the complete insulation of the engine components, like pistons, liner, firedeck and valves, has been simulated. This analysis has showed that the piston is the component with the greatest potential for the in-cylinder heat transfer reduction and for Brake Specific Fuel Consumption (BSFC) reduction, followed by firedeck, liner and valves. Afterwards, the study has been focused on the impact of different piston Thermal Barrier Coatings (TBCs) on heat transfer, performance and wall temperatures.
2017-07-24
Technical Paper
2017-01-5003
Igor V. Gritsuk, Valery Aleksandrov, Sergii Panchenko, Artur Kagramanian, Oksana Sobol, Aleksandr Sobolev, Roman Varbanets
Abstract Thermal control of a vehicle engine operation is a key aspect of the development of a vehicle warming-up systems. The use of heat accumulators and phase transition heat-accumulating materials is perspective. The given article describes the ways of improving thermal properties of phase transition heat-accumulating materials in the processes of their designing, the efficient ways of heat transfer from phase transition heat-accumulating materials to heat carrying agent of heat accumulators and then to vehicles. To create reliable phase transition heat-accumulating materials, different ways of their realization are suggested. One of them is the construction of the corresponding phase diagrams to determine an optimal composition of phase transition heat-accumulating materials with higher thermal properties to operate in a given temperature range.
2017-07-10
Technical Paper
2017-28-1951
K Nantha Gopal, B. Ashok, Rishabh Bahuguna, Tanmay Prasad
Abstract Thermal management is one of the most challenging and innovative aspects of the automotive industry. The efficiency of the vehicle cooling framework unequivocally relies upon the air stream through the radiator core. Significant advances in thermal management are being embraced in the field of radiator material and coolant. The radiator shouldn't be exclusively credited for the reliable cooling of the engine. There are other auto parts that play an essential role in keeping engine temperature at a manageable level. The fan-shroud assembly is an important component of the cooling system. While the fan is responsible for drawing in air, the fan shroud's job is to ensure uniform air distribution to the radiator core. By assisting airflow in the engine compartment the fan shroud helps in dismissing excess heat from the engine. This assembly also prevents the recirculation of heated air through the cooling fan.
2017-06-29
Journal Article
2017-01-9279
Davide Di Battista, Roberto Cipollone
Abstract The use of reciprocating internal combustion engines (ICE) dominates the sector of the on-road transportation, both for passengers and freight. CO2 reduction is the present technological driver, considering the major worldwide greenhouse reduction targets committed by most governments in the western world. In the near future (2020) these targets will require a significant reduction with respect to today’s goals, reinforcing the importance of reducing fuel consumption. In ICEs more than one third of the fuel energy used is rejected into the environment as thermal waste through exhaust gases. Therefore, a greater fuel economy could be achieved if this energy is recovered and converted into useful mechanical or electrical power on board. For long haul vehicles, which run for hundreds of thousands of miles per year at relatively steady conditions, this recovery appears especially worthy of attention.
2017-06-27
Journal Article
2017-01-9179
Mike Liebers, Dzmitry Tretsiak, Sebastian Klement, Bernard Bäker, Peter Wiemann
Abstract A vital contribution for the development of an environmental friendly society is improved energy efficiency in public transport systems. Increased electrification of these systems is essential to achieve the high objectives stated. Since the operating range of an electrical vehicle is heavily influenced of the available energy, which primarily is used for propulsion and thermal passenger comfort, all heat losses in the vehicle systems must be minimized. Especially for urban buses, the unwanted heat losses through open doors while passengers are boarding, have to be controlled. These energy fluxes are due to the large temperature gradients generated between in- and outdoor conditions and to install air-walls in the door opening areas have turned out to be a promising technical solution. Based on air-wall technologies used for climate control in buildings, this paper presents an experimental investigation on the reduction of heat losses in the door opening of urban buses.
2017-05-24
Technical Paper
2017-36-0011
J. Ocampo, S. Jelic, J. Han
Abstract Thermal performance of a brake system is one of the key attributes in a new vehicle development process. Adequate brake cooling characteristics are part of the vehicle performance and safety requirements. The design of a new brake system, however, can be a complex task from a thermal engineering perspective, particularly because of complex interactions between the brake component and the rest of the vehicle. Frequently, the vehicle integration issues are the most serious challenges for brake engineers. There are considerations on how much heat should be dissipated from a single and/or consecutive braking events vs. how much cooling can be provided to the brake corner. Design issues such as where to direct the cooling air to how much flexibility is allowed while complying with other requirements from the studio and aero teams. For a brake engineer, the priority is to maximize cooling to the brake corner and prevent system failure.
2017-03-28
Technical Paper
2017-01-1737
Piyapong Premvaranon, Jenwit Soparat, Apichart Teralapsuwan, Sutee Olarnrithinun
Abstract Beyond the modern design and illumination quality of automotive lamps, thermal management plays a crucial role and must be fulfilled in the early stages of the design process. An excessive thermal radiation from incandescent bulb can cause a severe thermal degradation of plastic parts such as housing or optical lens. Hence, to assess such impact of heat on the plastic parts, thermal analysis of a license plate lamp was investigated by a proposed technique combining computational fluid dynamics (CFD) and ray tracing mapping method. Then, the accuracy and computational cost of the method were compared with thermal results obtained by a thermal radiation model using Monte Carlo (MC) technique for calculating radiation effect coupled with CFD in heat transfer analysis. Finally, a comparison of temperature results from both techniques were validated with practical thermal measurements of license plate lamp prototype.
2017-03-28
Technical Paper
2017-01-0184
Miyoko Oiwake, Ozeki Yoshiichi, Sogo Obata, Hideaki Nagano, Itsuhei Kohri
Abstract In order to develop various parts and components for hybrid electric vehicles, understanding the effect of their structure and thermal performance on their fuel consumption and cruising distance is essential. However, this essential information is generally not available to suppliers of vehicle parts and components. In this report, following a previous study of electric vehicles, a simple method is proposed as the first step to estimate the algorithm of the energy transmission and then the cruising performance for hybrid electric vehicles. The proposed method estimates the cruising performance using only the published information given to suppliers, who, in general, are not supplied with more detailed information. Further, an actual case study demonstrating application of the proposed method is also discussed.
2017-03-28
Technical Paper
2017-01-0157
Forrest Jehlik, Simeon Iliev, Eric Wood, Jeff Gonder
Abstract This work details two approaches for evaluating transmission warming technology: experimental dynamometer testing and development of a simplified transmission efficiency model to quantify effects under varied real world ambient and driving conditions. Two vehicles were used for this investigation: a 2013 Ford Taurus and a highly instrumented 2011 Ford Fusion (Taurus and Fusion). The Taurus included a production transmission warming system and was tested over hot and cold ambient temperatures with the transmission warming system enabled and disabled. A robot driver was used to minimize driver variability and increase repeatability. Additionally the instrumented Fusion was tested cold and with the transmission pre-heated prior to completing the test cycles. These data were used to develop a simplified thermally responsive transmission model to estimate effects of transmission warming in real world conditions.
2017-03-28
Technical Paper
2017-01-0158
Masaaki Nakamura, Koichi Machida, Kiyohiro Shimokawa
Abstract A diesel engine is advantageous in its high thermal efficiency, however it still wastes about 50% of total input energy to exhaust and cooling losses. A feasibility study of thermoacoustic refrigerator was carried out as one of the means to recuperate waste heat. The thermoacoustic refrigerator prototyped for this study showed a capability to achieve cooling temperature lower than -20 degree C, which indicated that the system has a potential to be used in refrigerator trucks not only for cargo compartment cooling but also for cabin cooling.
2017-03-28
Technical Paper
2017-01-0150
Ankit Kumar Shukla, Raj Dhami, Aashish Bhargava, Sanjay Tiwari
Abstract In the current landscape of commercial vehicle industry, fuel economy is one of the major parameter for fleet owner’s profitability as well as greenhouse gasses emission. Less fuel efficiency results in more fuel consumption; use of conventional fuel in engines also makes environment polluted. The rapid growth in fuel prices has led to the demand for technologies that can improve the fuel efficiency of the vehicle. Phase change material (PCMs) for Thermal energy storage system (TES) is one of the specific technologies that not only can conserve energy to a large extent but also can reduce emission as well as the dependency on convention fuel. There is a great variety of PCMs that can be used for the extensive range of temperatures, making them attractive in a number of applications in automobiles.
2017-03-28
Technical Paper
2017-01-0152
Gang Liu, Zheng Zhao, Hao Guan, Chunhui Zhang, Dingwei Gao, Yongwei Cao
Abstract Advanced technology of thermal management is an effective method to reduce fuel consumption. There are several different technologies for coolant control, for example, electric water pump, split cooling and coolant control module. Through 1D thermal management simulation, coolant control module was chose for the test due to the best benefit for fuel consumption under NEDC cycle. 1D thermal management simulation model includes vehicle, cooling system, lubrication system and detailed engine model with all friction components. Coolant control module is designed to fix on 2.0L turbocharger GDI gasoline and to control 5 coolant ways, including radiator, by-pass, engine oil cooler, cabin heater and transmission oil cooler. The prototype is designed and made. The function and strategy is verified on designed test-bed. The vehicle with coolant control module is running under NEDC cycle.
2017-03-28
Technical Paper
2017-01-0154
Sudhi Uppuluri, Hemant R Khalane, Ajay Naiknaware
Abstract With the upcoming regulations for fuel economy and emissions, there is a significant interest among vehicle OEMs and fleet managers in developing computational methodologies to help understand the influence and interactions of various key parameters on Fuel Economy and carbon dioxide emissions. The analysis of the vehicle as a complete system enables designers to understand the local and global effects of various technologies that can be employed for fuel economy and emission improvement. In addition, there is a particular interest in not only quantifying the benefit over standard duty-cycles but also for real world driving conditions. The present study investigates impact of exhaust heat recovery system (EHRS) on a typical 1.2L naturally aspirated gasoline engine passenger car representative of the India market.
2017-03-28
Technical Paper
2017-01-0144
Zhijia Yang, Song Lan, Richard Stobart, Edward Winward, Rui Chen, Iain Harber
Abstract The application of state-of-art thermoelectric generator (TEG) in automotive engine has potential to reduce more than 2% fuel consumption and hence the CO2 emissions. This figure is expected to be increased to 5%~10% in the near future when new thermoelectric material with higher properties is fabricated. However, in order to maximize the TEG output power, there are a few issues need to be considered in the design stage such as the number of modules, the connection of modules, the geometry of the thermoelectric module, the DC-DC converter circuit, the geometry of the heat exchanger especially the hot side heat exchanger etc. These issues can only be investigated via a proper TEG model. The authors introduced four ways of TEG modelling which in the increasing complexity order are MATLB function based model, MATLAB Simscape based Simulink model, GT-power TEG model and CFD STAR-CCM+ model. Both Simscape model and GT-Power model have intrinsic dynamic model performance.
2017-03-28
Technical Paper
2017-01-0141
Ray Host, Peter Moilanen, Marcus Fried, Bhageerath Bogi
Abstract Future vehicle North American emissions standards (e.g., North American Tier 3 Bin 30 or LEVIII SULEV 30) require the exhaust catalyst to be greater than 80% efficient by 20 seconds after the engine has been started in the Federal Test Procedure. Turbocharged engines are especially challenged to deliver fast catalyst light-off since the presence of the turbocharger in the exhaust flow path significantly increases exhaust system heat losses. A solution to delivering cost effective SULEV 30 emissions in turbocharged engines is to achieve fast catalyst light-off by reducing exhaust system heat losses in cold start, without increasing catalyst thermal degradation during high load operation. A CAE methodology to assess the thermal performance of exhaust system hardware options, from the exhaust port to the catalyst brick face is described, which enables compliance with future emissions regulations.
2017-03-28
Technical Paper
2017-01-0142
Chunhui Zhang, Mesbah Uddin, Lee Foster
Abstract The demand for better fuel economy pushed by both consumer and Environmental Protection Agency (EPA), made OEMs to put more effort on other areas beside vehicle external aerodynamics. As one of these areas, under-hood aero-thermal management has taken an important role in the new road vehicle design process, due to the combination of growing engine power demands, utilization of sophisticated under-hood and underbody devices, and emission regulations. The challenge of the under-hood aerothermal management is not only due to the complexity of under-hood compartment, but also as a result of the complex heat transfer phenomena involving conduction, convention and thermal radiation. In this study, 3D CFD simulations were used to investigate the under-hood aerothermal flow features. The full vehicle model with detailed under-hood components used in this study is a Hyundai Veloster. A commercial CDF code Star-CCM+ version 11.04 from CD-adapco was used to run all the simulations.
2017-03-28
Technical Paper
2017-01-0124
V N Bhasker, Abhinav Agarwal, Abhishek Sharma, Avisek Das, Nirajkumar Mishra
Abstract Vehicle heat management has become a serious concern due to escalating under-hood and exhaust temperatures. Compact vehicle packaging caused by downsizing has further magnified this concern. In an automobile, fuel is stored in a metallic or plastic fuel tank. In addition to fuel storage, temperature inside fuel tank has to be maintained at a certain limit in order to control high fuel evaporation rate and prevent deterioration of parts. The fuel tank surface temperature is governed by heat rejection from the engine, exhaust system and heat radiated from the road. Generally, mechanical shielding has been found to be an efficient defense to the heat management problem. However ‘what to shield’, ‘where to place the shield’ and ‘how to shield’ are the major challenges. This paper describes a methodology followed to reduce temperature on fuel tank surface by varying material, geometry and layout of heat shields.
2017-03-28
Technical Paper
2017-01-0125
Marco Pizzi, Mauro Zorzetto, Alberto Barbano, Piercarlo Merlano, Luca Vercellotti
Abstract The emission reduction in gasoline and diesel engines is driving the introduction of systems implementing additives in liquid form: in particular water for injection systems in gasoline engines and urea solutions (AD-blue) in SCR (Selective Catalytic Reduction) systems in diesel engines. Owing to water and AD-Blue can freeze in the car operative temperature range, the tanks must be equipped with heaters to guarantee a sufficient amount of additives in liquid form. Currently used technologies are ceramic PTC (Positive Temperature Coefficient) elements and distributed metal resistors. Ceramic PTC based heaters concentrate all the power in small volumes. They need thermally conductive elements distributing the power over a wide area. The assembly is complex and the cost of the metal parts and related packaging technologies used to insulate the heater from the environment (water or urea) is typically high. Metal resistors are cheaper but must be controlled in current.
2017-03-28
Technical Paper
2017-01-0937
David Culbertson, James Pradun, Magdi Khair, Jeff Diestelmeier
Abstract Tightening regulations throughout the world demand a reduction in fuel consumption and NOX emission levels, creating an increasing need for additional heat for SCR aftertreatment. A durable and low cost heating system is needed for vehicles with hybrid or 24Vdc electricity. Recent development efforts have resulted in much smaller and lower cost heating systems for electrical systems ranging from 400 to 24Vdc. Test results demonstrate the feasibility of reducing the size of the heater and the relationship of heater power to the amount of time required to heat the exhaust. Intelligent solid state switching enables the heater to be smaller without compromising durability.
2017-03-28
Technical Paper
2017-01-1207
Satyam Panchal, Scott Mathewson, Roydon Fraser, Richard Culham, Michael Fowler
Abstract Lithium-ion batteries, which are nowadays common in laptops, cell phones, toys, and other portable electronic devices, are also viewed as a most promising advanced technology for electric and hybrid electric vehicles (EVs and HEVs), but battery manufacturers and automakers must understand the performance of these batteries when they are scaled up to the large sizes needed for the propulsion of the vehicle. In addition, accurate thermo-physical property input is crucial to thermal modeling. Therefore, a designer must study the thermal characteristics of batteries for improvement in the design of a thermal management system and also for thermal modeling. This work presents a purely experimental thermal characterization in terms of measurement of the temperature gradient and temperature response of a lithium-ion battery utilizing a promising electrode material, LiFePO4, in a prismatic pouch configuration.
2017-03-28
Journal Article
2017-01-1213
Yilin Yin, Zhong Zheng, Song-Yul Choe
Abstract Analysis of thermal behavior of Lithium ion battery is one of crucial issues to ensure a safe and durable operation. Temperature is the physical quantity that is widely used for analysis, but limited for accurate investigations of behavior of heat generation of battery because of sensitivities affected by heat transfer in experiments. Calorimeter available commercially is widely used to measure the heat generation of battery, but does not follow required dynamics because of a relatively large thermal time constant given by cavity and a limited heat transfer capability. In this paper, we proposed a highly dynamic calorimeter that was constructed using two thermoelectric devices (TEMs). For the design of the calorimeter and its calibration, a printed circuit board (PCB) with the same size as the battery was used as a dummy load to generate controlled heat.
2017-03-28
Journal Article
2017-01-1215
Peter Haussmann, Joachim Melbert
Abstract Battery safety is the most critical requirement for the energy storage systems in hybrid and electric vehicles. The allowable battery temperature is limited with respect to the battery chemistry in order to avoid the risk of thermal runaway. Battery temperature monitoring is already implemented in electric vehicles, however only cell surface temperature can be measured at reasonable cost using conventional sensors. The internal cell temperature may exceed the surface temperature significantly at high current due to the finite internal electrical and thermal cell resistance. In this work, a novel approach for internal cell temperature measurement is proposed applying on board impedance spectroscopy. The method considers the temperature coefficient of the complex internal cell impedance. It can be observed by current and voltage measurements as usually performed by standard battery management systems.
2017-03-28
Technical Paper
2017-01-1217
Jiangong Zhu, Zechang Sun, Xuezhe Wei, Haifeng Dai
Abstract An alternating current (AC) heating method for a NMC lithium-ion battery with 8Ah capacity is proposed. The effects of excitation frequency, current amplitudes, and voltage limit condition on the temperature evolution are investigated experimentally. Current amplitudes are set to 24A(3C), 40(5C), and 64A(8C), and excitation frequencies are set to 300Hz, 100Hz, 30Hz, 10Hz, 5Hz, and 1Hz respectively. The voltage limitations are necessary to protect cells from overcharge and over-discharge. Therefore the voltage limit condition (4.2V/2.75V, 4.3V/2.65V, and 4.4V/2.55V) are also considered in depth to verify the feasibility of the AC heating method. The temperature rises prominently as the current increases, and the decrement of frequencies also lead to the obvious growth of battery temperature. The battery obtain the maximum temperature rise at 64A and 1Hz, which takes 1800s to heat up the battery from -25°C to 18°C.
2017-03-28
Technical Paper
2017-01-0521
Richard Merrett, John Murray, Doug Kolak
Abstract The development of experimental ORC systems is an extremely complex, time consuming and costly task. Running a range of experiments on a number of different component configurations may be prohibitively expensive and subject to equipment issues and failures. Yet ORC systems offer significant potential for automotive manufacturers to improve vehicle efficiency, reduce fuel consumption and vehicle emissions; the technology is particularly relevant for those involved in the design and/or manufacture of heavy duty trucks. This paper is focused on the validation of a computational ORC system simulation tool against a number of SAE published test results based on the European Stationary Cycle. Such studies on industry standard systems are essential in order to help promote confidence in a virtual prototype approach.
Viewing 1 to 30 of 282

Filter