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This talk will present an overview of the newly published DO-326/ED-202 "Airworthiness Security Process Specification". Presenter Daniel P. Johnson, Honeywell

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.

This study investigates the use of machine learning methods for the selection of energy storage devices in military electrified vehicles. Powertrain electrification relies on proper selection of energy storage devices, in terms of chemistry, size, energy density, and power density, etc. Military vehicles largely vary in terms of weight, acceleration requirements, operating road environment, mission, etc. This study aims to assist the energy storage device selection for military vehicles using the data-drive approach. We use Machine Learning models to extract relationships between vehicle characteristics and requirements and the corresponding energy storage devices. After the training, the machine learning models can predict the ideal energy storage devices given the target vehicles design parameters as inputs. The predicted ideal energy storage devices can be treated as the initial design and modifications to that are made based on the validation results.

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.

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.

Laser excitation wavelengths for two-line planar laser-induced fluorescence (PLIF) of 3-pentanone have been optimized for simultaneous imaging of temperature and composition under engine-relevant conditions. Validation of the diagnostic was performed in a motored optical IC engine seeded homogeneously with 3-pentanone. PLIF measurements of the uniform mixture during the compression stroke were used to measure the average temperature and to access the random uncertainty in the measurements. To determine the accuracy of the temperature measurements, experimental average temperatures were compared to values computed assuming isentropic compression and to the output of a tuned 1-D engine simulation. The comparison indicated that the absolute accuracy of the temperature measurements is better than ±5%. Probability density functions (PDFs) calculated from the single-shot images were used to estimate the precision of the measurements.

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.

Many experimental efforts to track fuel-air-residual mixture preparation in internal combustion engines have employed laser induced fluorescence (LIF) of tracers. Acetone and 3-pentanone are often chosen as tracers because of their relatively strong LIF signal, weak quenching, and reasonable match to thermo-chemical properties of common fuels such as iso-octane. However, the addition of these tracers to fuel-air mixtures could affect combustion behavior. In this work, we assess these effects to better understand limitations of tracer-based engine measurements. The effects of tracer seeding on combustion phasing, duration, and variation are studied in an HCCI engine using a recompression strategy to accommodate single- and multi-stage-ignition fuels.

Negative valve overlap (NVO) is a valve strategy employed to retain and recompress residual burned gases to assist HCCI combustion, particularly in the difficult regime of low-load operation. NVO allows the retention of large quantities of hot residual burned gases as well as the possibility of fuel addition for combustion control purposes. Reaction of fuel injected during NVO increases charge temperature, but in addition could produce reformed fuel species that may affect main combustion phasing. The strategy holds potential for controlling and extending low-load HCCI combustion. The goal of this work is to demonstrate the feasibility of applying two-wavelength PLIF of 3-pentanone to obtain simultaneous, in-cylinder temperature and composition images during different parts of the HCCI/NVO cycle. Measurements are recorded during the intake and main compression strokes, as well as during the more challenging periods of NVO recompression and re-expansion.

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).

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.

Heat transfer is one of the largest causes of exergy destruction in modern engines. In this paper, exergy distribution modeling was used to determine the potential of reduced engine heat transfer to provide significant gains in engine efficiency. As known from prior work, of itself, reducing heat transfer creates only a small increase in efficiency-most of the exergy is redirected into the exhaust stream-requiring both mechanical and thermal recovery of the exhaust exergy. Mechanical regeneration, through turbocharging and over-expansion, can lead to efficiencies exceeding 50%. Adding thermal regeneration, through high enthalpy steam injection or a bottoming cycle, can increase the efficiency potential to approximately 60%. With implementation of both mechanical and thermal regeneration, the only remaining cause of substantial exergy destruction is the combustion process.

A particle tracking velocimetry (PTV) system has been developed to measure two dimensional velocity fields in a motored axisymmetric engine with a transparent cylinder. The intake flow was seeded with phenolic microballoons (40 μm hollow spheres) and illuminated by a 1 mm thick horizontal sheet of pulsed laser light from a 25 Watt copper vapor laser capable of 30 ns pulses. Photographs containing tracks of dots representing the multiply exposed path of each particle were produced. These images were digitized by a custom scanner capable of 3456 by 5184 pixel resolution and binarized using an iterative threshold routine in order to locate the particles. Software then determined how the individual particles are organized into tracks and presented the results for operator verification. Velocity magnitude and direction were computed for each track and the results were interpolated to a fixed grid for further analysis.

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.

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.

Standard CFD methods require a mesh that fits the boundaries of the computational domain. For a complex geometry the generation of such a grid is time-consuming and often requires modifications to the model geometry. This paper evaluates the Immersed Boundary (IB) approach which does not require a boundary-conforming mesh and thus would speed up the process of the grid generation. In the IB approach the CAD surfaces (in Stereo Lithography -STL- format) are used directly and this eliminates the surface meshing phase and also mitigates the process of the CAD cleanup. A volume mesh, consisting of regular, locally refined, hexahedrals is generated in the computational domain, including inside the body. The cells are then classified as fluid, solid and interface cells using a simple ray-tracing scheme. Interface cells, correspond to regions that are partially fluid and are intersected by the boundary surfaces.

Computational fluid dynamic (CFD) simulations that include realistic combustion/emissions chemistry hold the promise of significantly shortening the development time for advanced high-efficiency, low-emission engines. However, significant challenges must be overcome to realize this potential. This paper discusses these challenges in the context of diesel combustion and outlines a technical program based on the use of surrogate fuels that sufficiently emulate the chemical complexity inherent in conventional diesel fuel.

The development of surrogate mixtures that represent gasoline combustion behavior is reviewed. Combustion chemistry behavioral targets that a surrogate should accurately reproduce, particularly for emulating homogeneous charge compression ignition (HCCI) operation, are carefully identified. Both short and long term research needs to support development of more robust surrogate fuel compositions are described. Candidate component species are identified and the status of present chemical kinetic models for these components and their interactions are discussed. Recommendations are made for the initial components to be included in gasoline surrogates for near term development. Components that can be added to refine predictions and to include additional behavioral targets are identified as well. Thermodynamic, thermochemical and transport properties that require further investigation are discussed.

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.

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.