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Journal Article

New Methodology for Transient Engine Rig Experiments for Efficient Parameter Tuning

2013-12-20
2013-01-9043
When performing catalyst modeling and parameter tuning it is desirable that the experimental data contain both transient and stationary points and can be generated over a short period of time. Here a method of creating such concentration transients for a full scale engine rig system is presented. The paper describes a valuable approach for changing the composition of engine exhaust gas going to a DOC (or potentially any other device) by conditioning the exhaust gas with an additional upstream DOC and/or SCR. By controlling the urea injection and the DOC bypass a wide range of exhaust compositions, not possible by only controlling the engine, could be achieved. This will improve the possibilities for parameter estimation for the modeling of the DOC.
Journal Article

Parameter Estimation of a DOC from Engine Rig Experiments with a Discretized Catalyst Washcoat Model

2014-07-01
2014-01-9049
Parameter tuning was performed against data from a full scale engine rig with a Diesel Oxidation Catalysts (DOC). Several different catalyst configurations were used with varying Pt loading, washcoat thickness and volume. To illustrate the interplay between kinetics and mass transport, engine operating points were chosen with a wide variation in variables (inlet conditions) and both transient and stationary operation was used. A catalyst model was developed where the catalyst washcoat was discretized as tanks in series both radially and axially. Three different model configurations were used for parameter tuning, evaluating three different approaches to modeling of internal transport resistance. It was concluded that for a catalyst model with internal transport resistance the best fit could be achieved if some parameters affecting the internal mass transport were tuned in addition to the kinetic parameters.
Journal Article

Modeling and Characterization of a Novel Porous Metallic Foam Inside Ducts

2015-06-15
2015-01-2203
A novel porous metallic foam has been studied in this work. This composite material is a mixture of resin and hollow spheres. It is lightweight, highly resistive to contamination and heat, and is capable of providing similar or better sound absorption compared to the conventional porous absorbers, but with a robust and less degradable properties. Several configurations of the material have been tested inside an expansion chamber with spatially periodic area changes. Bragg scattering was observed in some configurations with certain lattice constants. The acoustic properties of this material have been characterized from the measurement of the two-port matrix across a cylindrical sample. The complex density and speed of sound can be extracted from the transfer matrix using an optimization technique. Several models were developed to validate the effect of this metallic foam using Finite Elements and the Two-port Theory.
Journal Article

Health Ready Components-Unlocking the Potential of IVHM

2016-04-05
2016-01-0075
Health Ready Components are essential to unlocking the potential of Integrated Vehicle Health Management (IVHM) as it relates to real-time diagnosis and prognosis in order to achieve lower maintenance costs, greater asset availability, reliability and safety. IVHM results in reduced maintenance costs by providing more accurate fault isolation and repair guidance. IVHM results in greater asset availability, reliability and safety by recommending preventative maintenance and by identifying anomalous behavior indicative of degraded functionality prior to detection of the fault by other detection mechanisms. The cost, complexity and effectiveness of the IVHM system design, deployment and support depend, to a great extent, on the degree to which components and subsystems provide the run-time data needed by IVHM and the design time semantic data to allow IVHM to interpret those messages.
Journal Article

A Note on the Applicability of Thermo-Acoustic Engines for Automotive Waste Heat Recovery

2016-04-05
2016-01-0223
A thermo-acoustic engine is a device converting thermal energy into high amplitude acoustic waves that can be harvested, for example, to obtain electricity. The core of the device is a stack/regenerator along which a temperature gradient is created using one hot and one cold heat exchanger. Correctly designed, the thermal interaction between the working fluid and the regenerator assists in amplifying incident acoustic waves. Previous studies have indicated good efficiency obtained with a system of low geometrical complexity. However, for the practical application of this technique it is vital to understand and identify critical design parameters and operating conditions. This is of special interest in automotive applications where the operating conditions vary significantly over a drive cycle. This works aims at providing a framework for studying the net power generation over a drive cycle.
Journal Article

Computational Fluid Dynamics Calculations of Turbocharger's Bearing Losses

2010-05-05
2010-01-1537
Fuel consumption in internal combustion engines and their associated CO2 emissions have become one of the major issues facing car manufacturers everyday for various reasons: the Kyoto protocol, the upcoming European regulation concerning CO2 emissions requiring emissions of less than 130g CO2/km before 2012, and customer demand. One of the most efficient solutions to reduce fuel consumption is to downsize the engine and increase its specific power and torque by using turbochargers. The engine and the turbocharger have to be chosen carefully and be finely tuned. It is essential to understand and characterise the turbocharger's behaviour precisely and on its whole operating range, especially at low engine speeds. The characteristics at low speed are not provided by manufacturers of turbochargers because compressor maps cannot be achieve on usual test bench.
Journal Article

A Balanced Approach for Securing the OBD-II Port

2017-03-28
2017-01-1662
The On-Board Diagnostics II (OBD-II) port began as a means of extracting diagnostic information and supporting the right to repair. Self-driving vehicles and cellular dongles plugged into the OBD-II port were not anticipated. Researchers have shown that the cellular modem on an OBD-II dongle may be hacked, allowing the attacker to tamper with the vehicle brakes. ADAS, self-driving features and other vehicle functions may be vulnerable as well. The industry must balance the interests of multiple stakeholders including Original Equipment Manufacturers (OEMs) who are required to provide OBD function, repair shops which have a legitimate need to access the OBD functions, dongle providers and drivers. OEMs need the ability to protect drivers and manage liability by limiting how a device or software application may modify the operation of a vehicle.
Journal Article

Development of a Lube Filter with Controlled Additive Release for Modern Heavy Duty Diesel Engines Utilizing EGR

2008-10-07
2008-01-2644
As on-highway heavy-duty diesel engine designs have evolved to meet tighter emission regulations, the crankcase environment for heavy-duty engine lubricants has become more challenging. The introduction of Exhaust Gas Recirculation (EGR) has allowed for significant reductions of exhaust emissions, but has led to increased oxidation and acid build-up in the lubricant. Engine lubricant quality is important to help ensure engine durability, engine performance, and reduce maintenance downtime. Increased acidity and oxidation accelerate the rate at which the lubricant quality is degraded and hence shorten its' useful life. This paper explores the use of a lube filter with a controlled additive release to maintain lubricant quality.
Journal Article

Incorporation of Atmospheric Neutron Single Event Effects Analysis into a System Safety Assessment

2011-10-18
2011-01-2497
Atmospheric Neutron Single Event Effects (SEE) are widely known to cause failures in all electronic hardware, and cause proportionately more failures in avionics equipment due to the use altitude. In digital systems it is easy to show how SEE can contribute several orders of magnitude more faults than random (hard) failures. Unfortunately, current avionics Safety assessment methods do not require consideration of faults from SEE. AVSI SEE Task Group (Aerospace Vehicle Systems Institute Committee #72, on Mitigating Radiation Effects in Avionics) is currently coordinating development of an atmospheric Neutron Single Event Effects (SEE) Analysis method. This analysis method is a work in progress, in close collaboration with SAE S-18 and WG-63 Committees (Airplane Safety Assessment Committee). The intent is to include this method as part of current revisions to ARP4761 (Guidelines and Methods for Conducting the Safety Assessment Process on Civil Airborne Systems and Equipment).
Journal Article

Experimental and Numerical Investigation of Wheel Housing Aerodynamics on Heavy Trucks

2012-04-16
2012-01-0106
Wheel and underbody aerodynamics have become important topics in the search to reduce the aerodynamic drag of the heavy trucks. This study aims to investigate, experimentally as well as numerically, the local flow field around the wheels and in the wheel housing on a heavy truck; and how different approaches to modelling the wheel rotation in CFD influences the results. Emphasis is on effects due to ground simulation, and both moving ground and wheel rotation were requirements for this study. A 1:4-scale model of part of a heavy truck geometry has been developed. During the model design numerical simulations were used to optimise the shape, in order to replicate the flow field near the wheel of a complete truck. This was done by changing the flow angles of the incoming and exiting flows, and by keeping the mass flow rates in to, and out of, the wheel housing at the same ratios as in a reference full size vehicle.
Journal Article

Incorporating Atmospheric Radiation Effects Analysis into the System Design Process

2012-10-22
2012-01-2131
Natural atmospheric radiation effects have been recognized in recent years as key safety and reliability concerns for avionics systems. Atmospheric radiation may cause Single Event Effects (SEE) in electronics. The resulting Single Event Effects can cause various fault conditions, including hazardous misleading information and system effects in avionics equipment. As technology trends continue to achieve higher densities and lower voltages, semiconductor devices are becoming more susceptible to atmospheric radiation effects. To ensure a system meets all its safety and reliability requirements, SEE induced upsets and potential system failures need to be considered. The purpose of this paper is to describe a process to incorporate the SEE analysis into the development like-cycle. Background on the atmospheric radiation phenomenon and the resulting single event effects, including single event upset (SEU) and latch up conditions is provided.
Technical Paper

Thermally Stable Pt/Rh Catalysts

1997-10-01
972909
The increasing severity in emission standards around the world has been accompanied by the development of more active, durable catalysts. With a view to investigating the effects of high thermal aging on the catalyst performance and structure, the relationships of washcoat composition, washcoat structure, and PGM location with respect to catalyst activity were clarified using a model gas test, as well as physical and chemical characterization methods. The influence of newly developed washcoat components and PGM location on catalyst performance are also demonstrated by engine bench tests. The results obtained in this study indicate the newly developed Pt/Rh catalyst techologies are appropriate for future applications in which the catalyst will be exposed to extremely high temperature and flowrates.
Technical Paper

Mojacar Brake Wear and NVH: Dyno Simulation Concept

2007-10-07
2007-01-3959
Efficient development and testing of brake systems requires further substitution of expensive and time consuming vehicle testing by appropriate dynamometer testing. Some of the current simulation methods do not reflect the needs of engineering and the progress made in the development of test equipment. The lack of suitable procedures may cause unexpected delays in the realization of projects. Road load simulations for lifetime prediction on brake dynamometers have a long history, however never got a real break-through in Europe - possibly because the prediction quality and efficiency did not satisfy. This paper concentrates first on the analysis of the vehicle data recorded in Mojacar (Spain) which is a sign-off test for wear and noise for brands of Ford Motor Company for European market. Specific attention is given to different types of driving resistances and road profiles and to consideration of different methods for numerical description and comparison of road load data.
Technical Paper

Industry Activities Related to Aircraft Information Security

2007-09-17
2007-01-3919
Commercial transport aircraft have adopted TCP/IP based onboard networking technology to integrate information interchange. This change along with the addition of a TCP/IP based air-ground data link will permit the aircraft network to establish links with ground networks and be integrated into the airline enterprise network. There are many challenging considerations when connecting a remote network to an enterprise network. These challenges are multiplied when that remote network is constantly in motion, both physically and in terms of its link to the ground network. An important consideration in any enterprise network is the element of security. AEEC has published ARINC Report 811: Commercial Aircraft Information Security Concepts of Operation and Process Framework [1] as a guide for the airlines as they consider how to deal with this new challenge.
Technical Paper

Ambient Temperature Light-off Aftertreatment System for Meeting ULEV Emission Standards

1998-02-23
980421
It has long been recognized that the key to achieving stringent emission standards such as ULEV is the control of cold-start hydrocarbons. This paper describes a new approach for achieving excellent cold-start hydrocarbon control. The most important component in the system is a catalyst that is highly active at ambient temperature for the exothermic CO oxidation reaction in an exhaust stream under net lean conditions. This catalyst has positive order kinetics with respect to CO for CO oxidation. Thus, as the concentration of CO in the exhaust is increased, the rate of this reaction is increased, resulting in a faster temperature rise over the catalyst.
Technical Paper

Hydrocarbon Adsorber Technology

2007-04-16
2007-01-1434
Various government agencies such as EPA and CARB have established evaporative emission standards for light duty vehicles. To help the OEM's meet these emission standards for volatile organic compounds (VOC's), Honeywell has developed a hydrocarbon adsorber (HCA) approach to reduce hot soak emissions that escape through the air induction system. The HCA has a small footprint and is incorporated in the air filter housing while having a minimal impact on the air flow to the engine during normal operation. As required through EPA regulations it is permanently mounted to provide life of the vehicle durability. In this paper, the process for selecting the VOC adsorbent that functions within the parameters of the hot soak cycle and is regenerated under standard engine operation is discussed. An important part of this technology has been the development of a laboratory test that would simulate engine conditions and permit evaluation of various HCA prototypes.
Technical Paper

Diesel Fuel Desulfurization Filter

2007-04-16
2007-01-1428
The molecular filtration of sulfur components in ultra low sulfur diesel (ULSD) fuel is described. A comprehensive screening of potential sulfur removal chemistries has yielded a sorbent which has the capability to efficiently remove organo-sulfur components in ULSD fuel. This sorbent has been used to treat ULSD fuel on a heavy duty engine equipped with NOx adsorber after-treatment technology and has been shown to lengthen the time between desulfation steps for the NOx adsorber. The fuel properties, cetane number and aromatics content, etc., have not been changed by the removal of the sulfur in the fuel with the exception of the lubricity which is reduced.
Technical Paper

Development of Advanced Metallic Substrate Design for Close Coupled Converter Application

2007-04-16
2007-01-1262
The implementations of the Tier 2 and LEVII emission levels require fast catalyst light-off and fast closed loop control through high-speed engine management. The paper describes the development of innovative catalyst designs. During the development thermal and mechanical boundary conditions were collected and component tests conducted on test rigs to identify the emission and durability performance. The products were evaluated on a Super Imposed Test Setup (SIT) where thermal and mechanical loads are applied to the test piece simultanously and results are compared to accelerated vehicle power train endurance runs. The newly developed light-off catalyst with Perforated Foil Technology (PE) showed superior emission light-off characteristic and robustness.
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