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2015-09-06
Technical Paper
2015-24-2449
Mark Aaron Hoffman, Zoran Filipi
The limited operational range of Homogeneous Charge Compression Ignition engines is influenced by combustion chamber deposit accumulation and burn-off. Previous works have investigated in-situ combustion chamber deposit thermal properties with the end goal of replicating their increased temperature swing during compression and operability range shift in a manner which is independent of driving cycle. Combustion chamber deposit thermal diffusivity was found to differ depending on the location of deposit accumulation within the combustion chamber. These material property differences have been attributed to the spatially dependent interaction of deposits with the cylinder charge. This work establishes the methodology for determining the impact of directly injected gasoline on in-situ combustion chamber deposit thermal diffusivity.
2015-05-13
WIP Standard
AIR1657C
Metric (SI and CGS) and English units related to aerospace hydraulics are summarized. Conversion of units is provided as required. Fundamental fluid properties and physical laws governing fluid motion, pressure and other significant aspects are described in SI metric units. Examples of application to typical aerospace hydraulic system components are demonstrated.
2015-05-13
Technical Paper
2015-36-0009
Evandro Benincá, Mauricio da Silva, Ruy Alberto Bueno Jr., Vagner do Nascimento
Abstract One effect which is present in drum and disc brakes is the temperature. This effect significantly changes the vehicle and semi-trailer combinations performance, mainly in drum brakes that is more susceptible to this factor. High temperatures mean loss of efficiency, higher lining wear, brakes and rolling systems components life reduction and could be caused by many factors, which can be mentioned, overload, error in design and choice of brake system, speeding, over adjustment (dragging) and environment heat exchange. The challenge is to comprehend the relation between different brake configuration and how these configurations affects the temperatures generation on brake system, allowing that this factors can be evaluated during the project design. This paper aims to show a case study for a new brake family to be used in city bus application where the fleets are looking for better, safety, performance and low lining wear reduce the to increase the maintenance time.
2015-04-14
Journal Article
2015-01-0357
Huize Li, Predrag Hrnjak
Abstract This paper presents a method of utilizing infrared images to quantify the distribution of liquid refrigerant mass flow rate in microchannel heat exchangers, which are widely used in automobile air conditioning systems. In order to achieve quantification, a relationship is built between the liquid mass flow rate through each microchannel tube and the corresponding air side capacity calculated from the infrared measurement of the wall temperature. After being implemented in a heat exchanger model, the quantification method is validated against experimental data. This method can be used for several types of heat exchangers and it can be applied to various heat exchanger designs.
2015-04-14
Technical Paper
2015-01-0607
Xincheng Liang, Jingshan Zhao
Abstract This paper proposes a theoretical model to interpret the heat generation mechanism and thermal failure of shock absorber. For a common structure of double-tube shock absorber, all frictions between two contacting components of shock absorber are calculated particularly. The heat generation mechanism and heat distribution can be explained with the theoretical model. Thermal failure is a recurrent malfunction for traditional shock absorbers, which leads to shorten the service lives of vehicle components. Heat generation experiments are accomplished to validate the thermal degeneration of shock absorber. So this study is meaningful to develop a new system of vibration attenuation with satisfying reliability, which is essential to improve the riding comfort and handling stability of vehicles.
2015-04-14
Technical Paper
2015-01-1673
Seunghyun Lee, Yoonwoo Lee, Sungmoon Lee, Han Ho Song, Kyoungdoug Min, Hoimyung Choi
Abstract In this study, a correlation between the maximum heat release rate and vibrations from a diesel engine block was derived, and a methodology to determine the maximum heat release rate is presented. To investigate and analyze the correlation, an engine test and an actual road vehicle test were performed using a 1.6-L diesel engine. By varying the engine speed, load and main injection timing, the vibration signals from the engine block were measured and analyzed using a continuous wavelet transform (CWT). The results show that the maximum heat release rate has a strong correlation with the magnitude of the vibrations. A specific bandwidth, the vibration signals between 0.3∼1.5 kHz, was affected by the variation in the heat release rate. The vibrations excited by combustion lasted over 50 CAD; however, the signals during the period of 35 CAD after the start of injection had a dominant effect on the maximum heat release rate.
2015-04-14
Journal Article
2015-01-1157
Namwook Kim, Jongryeol Jeong, Aymeric Rousseau, Henning Lohse-Busch
Abstract For electrified vehicles, understanding the impact of temperature on vehicle control and performances becomes more important than before because the vehicle might consume more energy than conventional vehicles due to lack of the engine waste heat. Argonne has tested many advanced vehicles and analyzed the vehicle level control based on the test data. As part of its ongoing effort, Toyota Prius Plug-in Hybrid was tested in thermal environmental chamber, and the vehicle level control and performances are analyzed by observing the test results. The analysis results show that the control of the Plug-in Hybrid Electric Vehicle (PHEV) is similar with Prius Hybrid Electric Vehicle (HEV) when the vehicle is under a charge sustaining mode, and the vehicle tries to consume the electric energy first under a charge depleting mode.
2015-04-14
Journal Article
2015-01-1525
Rocky Khasow, Scott Best, Martin Agelin-Chaab, John Komar, Gary Elfstrom
Abstract Underbody vehicle flows are poorly understood given the comparatively small field of research to draw upon; even more so in the case of crosswinds. With the advent of electric and hybrid electric vehicles and their increased cooling demands, there is a need for a link between the aerodynamic flow field and the thermodynamic response. Thus underbody research considering a yawing vehicle was conducted on a Chevrolet Aveo5 hatchback. The vehicle was outfitted with a heat source to provide a baseline analysis along thermocouples, pressure probes and flow visualization tufts. The climatic wind tunnel at the University Of Ontario Institute Of Technology's Automotive Centre of Excellence provided video data of the tufts and thermal imaging data of the heat source.
2015-01-14
Technical Paper
2015-26-0192
Sourabh Shrivastava, Padmesh Mandloi
Abstract CFD simulations of an engine cooling system needs to resolve two aspects of the system; in-cylinder combustion and engine cooling. Underlying physics of an in-cylinder combustion process and heat transfer through engine cooling system requires very different time scales for resolution. This puts a limitation on practicality of solving the two problems simultaneously for any industrial case. Instead of solving the problem simultaneously, solution for an engine cooling system operating at a constant load can be derived using the coupled approach. This involves running two different CFD simulations: a transient in-cylinder simulation to model combustion in the engine, and a steady state CHT simulation using engine cooling system for heat transfer. These simulations are thermally coupled through boundary conditions and are performed in cyclic manner one after the other. Simulations are continued till the change in temperature with coupled cycles becomes insignificant.
2014-10-13
Technical Paper
2014-01-2559
Christopher Bannister
Abstract When evaluating the performance of new boosting hardware, it is a challenge to isolate the heat transfer effects inherent within measured turbine and compressor efficiencies. This work documents the construction of a lumped mass turbocharger model in the MatLab Simulink environment capable of predicting turbine and compressor metal and gas outlet temperatures based on measured or simulated inlet conditions. A production turbocharger from a representative 2.2L common rail diesel engine was instrumented to enable accurate gas and wall temperature measurements to be recorded under a variety of engine operating conditions. Initially steady-state testing was undertaken across the engine speed and load range in order that empirical Reynolds-Nusselt heat transfer relationships could be derived and incorporated into the model. Steady state model predictions were validated against further experimental data.
2014-10-13
Journal Article
2014-01-2713
Jianyi Tian, Hongming Xu, Ramadhas Arumugam Sakunthalai, Dai Liu, Cheng Tan, Akbar Ghafourian
Abstract Engine transient operation has attracted a lot of attention from researchers due to its high frequency of occurrence during daily vehicle operation. More emissions are expected compared to steady state operating conditions as a result of the turbo-lag problem. Ambient temperature has significant influences on engine transients especially at engine start. The effects of ambient temperature on engine-out emissions under the New European Driving Cycle (NEDC) are investigated in this study. The transient engine scenarios were carried out on a modern 3.0 L, V6 turbocharged common rail diesel engine fuelled with winter diesel in a cold cell within the different ambient temperature ranging between +20 °C and −7 °C. The engine with fuel, coolant, combustion air and lubricating oil were soaked and maintained at the desired test temperatures during the transient scenarios.
2014-09-30
Technical Paper
2014-36-0112
A. B. Chiaroni, Z. C. Silveira
Abstract This paper presents a thermal analysis of a sub-set drum/shoe brake lining of a braking system in a rear drum brake for a lightweight passenger vehicle with engines of up to 1,000 cc, for a future application to hybrid power trains. In academic databases, as well as free research database, it is difficult to find papers and even technical works which show the complete cycle of the design of an automotive braking system. It occurs mostly due to the confidentiality of industries and industrial parts suppliers, once the brake system is a product of high added value. In this study, transient temperature field distributions of the shoe lining were obtained by numerical simulations. Boundary conditions of the model were calculated according to a reference paper. The geometry and mechanical and thermal properties of the brake shoe lining were obtained from data provided by the manufacturer.
2014-09-28
Technical Paper
2014-01-2501
Abdulwahab A. Alnaqi, Suman Shrestha, David C. Barton, Peter C. Brooks
Abstract Aluminium alloys have been used extensively in the automotive industry to reduce the weight of a vehicle and improve fuel consumption which in turn leads to a reduction in engine emissions. The main aim of the current study is to replace the conventional cast iron rotor material with a lightweight alternative such as coated aluminium alloy. The main challenge has been to meet both the cost and functional demands of modern mass-produced automotive braking systems. A sensitivity analysis based on the Taguchi approach was carried out to investigate the effect of various parameters on the thermal performance of a typical candidate disc brake. Wrought aluminium disc brake rotors coated with alumina on the rubbing surfaces were determined to have the best potential for replacing the conventional cast iron rotor at reasonable cost. Optimisation of the structure was subsequently carried out using a genetic algorithm on the selected coated aluminium disc brake rotor.
2014-09-28
Journal Article
2014-01-2497
Bongkeun Choi
Abstract In this paper an effective technology of virtual thermal test of disc brake with several advanced analytic techniques was presented. With the virtual thermal test process, thermal performance of brake system could be easily evaluated without any possibility of great errors that used to happen in the past. In addition to the classical result of CFD, this virtual thermal test produced several valuable applications such as thermal deformation of rotor, optimization of thermal performance and estimation of braking distance.
2014-05-23
WIP Standard
J2020
This test method specifies the operating conditions for a fluorescent ultraviolet (UV) and condensation apparatus used for the accelerated exposure of various automotive exterior components. Specimen preparation, test duration, and performance evaluation procedures are addressed by each automotive manufacturerÕs material specifications. This SAE Standard may involve hazardous materials, operations, and equipment. This document does not purport to address all of the safety problems associated with its use. It is the responsibility of whoever uses this document to consult and establish appropriate and health practices and determine the applicability of regulatory limitations prior to use. Significance and Use This test method is designed to simulate extreme environmental conditions encountered on the outside of an automobile due to sunlight, heat, and to provide an acceleration of exposure for the purpose of predicting the performance of exterior automotive materials.
2014-04-01
Collection
This technical paper collection focusses on state of the art simulation technologies for modeling thermal systems and their application in the development and optimization of vehicle thermal management and fuel economy. The papers included will range from empirical, 1D modeling methods to three dimensional CFD models as well as coupled methods.
2013-11-13
Standard
J951_201311
The purpose of this SAE Information Report is to compare the results of Florida exposure at 45 deg from the horizontal, facing south, with those at deg from the horizontal, facing south, using various types and colors of automotive finishes.
2013-09-17
Journal Article
2013-01-2132
Jeffrey Morgan
Since the 1960's, lightning protection of aircraft has been an important design aspect, a concern for the flying public, aircraft manufacturers and the Federal Aviation Administration (FAA). With the implementation of major aircraft structures fabricated from carbon fiber reinforced plastic (CFRP) materials, lightning protection has become a more complicated issue to solve. One widely used material for lightning strike protection of CFRP structures within the aerospace industry is expanded metal foil (EMF). EMF is currently used in both military and commercial passenger aircraft. An issue that has historically been an area of concern with EMF is micro cracking of paint on the composite structure which can result in corrosion of the metal foil and subsequent loss of conductivity. This paper addresses the issues of stress and displacement in the composite structure layup which contribute to paint cracking caused by aircraft thermal cycling.
2012-11-19
Standard
J2212_201211
This SAE Recommended Practice specifies the operating procedures for a controlled irradiance, air-cooled xenon-arc apparatus used for the accelerated exposure of various automotive interior trim components. Test durations, as well as any exceptions to the sample preparation and performance evaluation procedures contained in this document, are covered in material specifications of the different automotive manufacturers.
2012-11-19
Standard
J2019_201211
This SAE Standard specifies the operating procedures for a controlled irradiance, air-cooled xenon-arc apparatus used for the accelerated exposure of various automotive exterior materials. The sample preparation, test durations, and performance evaluation procedures are covered in material specifications of the different automotive manufacturers.
2012-10-02
Technical Paper
2012-36-0304
Vinicius Durazzo Negrisolo, Ayres P. Andrade Filho, Edson Nascimento, Jose Marcelo Moura Silva, Edgard Ferraz
As part of any water pump development for engine cooling system, the interaction between materials with different coefficient of thermal expansion is unexceptional. Though in very specific applications where the coolant temperature is over 115°C several factors and variables can cause movement between parts because of the interference and coefficient of thermal expansion interaction combined with engine vibration and external loads. These factors were listed and evaluated considering several variables being validated physically and by simulation resulting on an optimized method to enhance this kind of fixation.
2012-09-10
Technical Paper
2012-01-1759
Zhelin Dong, Guohua Chen, Yankun Jiang, Chunfa Wang
A transient gas-solid heat transfer model for the 3-D (three-dimensional) coupling components in internal combustion chamber was built. In order to implement this model, a transient heat transfer program based on FEM (finite-element method) was developed, the KIVA3V code was improved, and a KIVA-FEM interface program was developed. A special treatment for the grid generation were designed and utilized. The 3-D transient non-uniform gas temperature field and convective heat transfer coefficient distribution near the combustion chamber wall can be obtained using this heat transfer model. In addition, both steady and transient temperature fields of the 3-D coupling component system of a gasoline engine were calculated and analyzed. The results show that the temporal and spatial non-uniformity of thermal boundary conditions has an important influence on the steady temperature field, transient temperature field and heat flux of the combustion chamber wall.
2012-09-10
Journal Article
2012-01-1760
Juan Du
This paper presents a method of calculating temperature field of the piston by using a wavelet neural network (WNN) to identify the unknown boundary conditions. Because of the complexity of the heat transfer and limitations of experimental conditions of heat transfer analysis of the piston in a diesel engine, boundary conditions of the piston temperature field were usually obtained empirically, and thus the result itself was uncertain. By employing the capability of resolution analysis from a wavelet neural network, the method obtains improved boundary heat transfer coefficients with a limited number of measured temperatures. Using FEA software iteratively, results show the proposed wavelet neural network analysis method improves the prediction of unknown boundary conditions and temperature distribution consistent with the experimental data with an acceptable error.
2011-12-06
Standard
J1310_201112
The scope of this SAE Information Report is to acquaint and inform those concerned with cold weather operation of diesel-powered machines and vehicles with the selection and application of electrically powered starting aids currently available. It deals specifically with the design, function, and application of line voltage electrically powered engine preheaters and battery warmers.
2011-12-06
Standard
J226_201112
This SAE Standard describes electric immersion engine preheaters for use in the coolant jacket of heavy-duty and intermediate size diesel engines. This document gives the dimensional information of the four basic styles of engine preheaters. The tables for each style will list the wattage commonly used. Small engines that typically require less than 600 W of preheat for cold weather starter are not covered by this document. These types of engines generally have very little space available to accommodate an immersion heater of the styles presented in this document. The purpose of this document is to establish commonality of engine preheater designs. The user of this document can use these current styles and wattages early on in their designing. This will give the user of this document a good engine preheater design.
2011-11-30
Standard
J1350_201111
This information report covers fuel fired pre-heaters which burn gasoline, diesel, or propane fuels. This type of heater must be used in remote areas where 110/220 V, 60 Hz electric power is not available, and is recommended anywhere an on-board self-contained system is required. The guidelines in this report are applicable, but not limited to, fuel burning heater installations on the off-road self-propelled work machine described in SAE Recommended Practice J1116.
Viewing 1 to 30 of 1073

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