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Standard

Reviews and Configuration Audits

2020-06-08
WIP
CMB6_6A

The objective of this course is to provide an in-depth understanding of the concepts and principles involved in the Review and Configuration Audit process. It is intended for an individual who has completed a basic introductory course in CM and who requires the deeper knowledge of a CM practitioner rather than a superficial overview.

Technical review and product audit practices described in this text are based on Government requirements. This emphasis is made because the Department of Defense DOD) represents a major customer of goods and services and because the referenced specifications and standards reflect good business practices refined over many years of usage. For commercial companies producing items for other companies or the public, many of these reviews and audits may not be formally implemented. They are, however, an integral and essential part of the systems engineering process.

Standard

Configuration and Data Management Training Course

2020-06-08
WIP
CMB6_9A

The functional and/or physical characteristics or hardware/software as set forth in technical documentation and achieved in a product.

What is Configuration Management?

A discipline applying technical and administrative direction and surveillance to (a) identify and document the functional and physical characteristics of a configuration item, (b) control changes to those characteristics, and (c) record and report change processing and implementation status.

Standard

Air Brake Valve - Performance Requirements

2020-05-13
WIP
J1410
This SAE Recommended Practice establishes minimum performance requirements for new pneumatic valves when tested in accordance with the test procedure outlined in SAE J1409. The performance requirements will include: a. Input-output performance b. Leakage characteristics c. Low temperature performance d. Elevated temperature performance e. Corrosion resistance performance f. Endurance testing g. Structural integrity
Technical Paper

Reconciling Simultaneous Evolution of Ground Vehicle Capabilities and Operator Preferences

2020-04-14
2020-01-0172
An objective evaluation of ground vehicle performance is a challenging task. This is further exacerbated by the increasing level of autonomy, dynamically changing the roles and capabilities of these vehicles. In the context of decision making involving these vehicles, as the capabilities of the vehicles improve, there is a concurrent change in the preferences of the decision makers operating the vehicles that must be accounted for. Decision based methods are a natural choice when multiple conflicting attributes are present, however, most of the literature focuses on static preferences. In this paper, we provide a sequential Bayesian framework to accommodate time varying preferences. The utility function is considered a stochastic function with the shape parameters themselves being random variables. In the proposed approach, initially the shape parameters model either uncertain preferences or variation in the preferences because of the presence of multiple decision makers.
Technical Paper

Review and Assessment of Multiaxial Fatigue Limit Models

2020-04-14
2020-01-0192
The purpose of this paper is to provide a comparison of multiaxial fatigue limit models and their correlation to experimental data. This paper investigates equivalent stress, critical plane and invariant-based multiaxial fatigue models. Several methods are investigated and compared based on ability to predict multiaxial fatigue limits from data published in literature. The equivalent stress based model developed by Lee, Tjhung and Jordan (LTJ), provides very accurate predictions of the fatigue limit under multiaxial loading due to its ability to account for non-proportional loading. This accuracy comes from the model constant which is calculated based on multiaxial fatigue data. This is the only model investigated that requires multiaxial fatigue testing to generate the model parameters. All other models rely on uniaxial test results.
Technical Paper

Numerical Study on the Influence of Convergent-Divergent Nozzle Structures on the In-Nozzle Flow and Jet Breakup Based on the OpenFOAM

2020-04-14
2020-01-1156
The non-conventional diesel nozzles have attracted more and more attention for their ability to promote jet breakup. In the present study, the internal nozzle flow and jet breakup relying on the convergent-divergent nozzle are investigated by combining the cavitation model and LES model with Multi-Fluid-Quasi-VOF model based on the OpenFOAM code. This is a novel method for which the interphase forces caused by the relative velocity of gas and liquid can be taken into account while sharpening the gas-liquid interface, which is able to accurately present the evolution processes of cavitation and jet breakup. Primarily, the numerical model was verified by the mass flow rate, spray momentum flux, discharge coefficient and effective jet velocity of the prototype Spray D nozzle from the literature.
Technical Paper

An Innovative Approach to Component Testing Using an Impact Sled

2020-04-14
2020-01-1331
Historically, crash development component testing has been conducted using gravity-based vertical drop towers. The drop tower carriage is loaded to a specified weight, raised to a specific height to achieve an energy target, and dropped onto the part. This long-used approach has significant limitations with respect to achievable speed and energy, part orientation, impact angle, useable impact surface, component size, etc. With the wide variance in simulating today’s global crash scenarios, a better approach is being developed using an impact sled. The most significant advantage of this system is that there is a much higher achievable speed and energy which can be controlled with precise accuracy. This paper will provide an overview of the impact sled test system, as well as the methodology used to conduct the testing. The overview will include the challenges faced during the development of the impact sled, as well as the need for accurate and precise component fixturing methods.
Technical Paper

Impact of High Performance Combustion Chamber Alloys on Fuel Efficiency

2020-04-14
2020-01-1338
Internal combustion engines have been developed for over one hundred and twenty years and are a very mature technology. Over this time, significant improvements in power density and brake thermal efficiency have been realized from improvements in design, processing and material properties. Huge advances in computer simulation capability over the past thirty years have enabled the former two categories to be explored and exploited very thoroughly, leaving materials specifications as the fundamental key to unlocking further efficiency gains. This paper summarizes the design advantages of a range of alternative materials developed for piston, ring connecting rod and bushing applications. A Ford Ecoboost 2.3l RS engine was selected as a baseline engine and the reciprocating parts were re-designed to take advantage of the improved characteristics of these materials.
Technical Paper

Augmented Reality Projection for Driver Assistance in Autonomous Vehicles

2020-04-14
2020-01-1035
Augmented Reality (AR), which involves the integration of digital information with our physical environment in real-time, has been steadily growing over the past few years, finding its way into multiple areas of our lives. Augmented Reality (AR) in automotive vehicles has contributed to revolutionizing the way passengers and drivers access information, acquire knowledge and integrate into the physical spaces and destinations visited. The studies produced concerning this field are still limited, particularly in the perception of how users adopt technology and what use they make of it. On the other hand, even more limited are the studies that consider the role of stakeholders in the implementation of AR technology.
Technical Paper

A Comparison of Componentization Constructs for Supporting Modularity in Simulink

2020-04-14
2020-01-1290
The Model-Based Development (MBD) paradigm is widely used for embedded controls development, with the MathWorks Simulink modelling environment being extensively used in the automotive industry. As production-scale Simulink models are typically large and complex, there exists a need to decompose them properly in order to facilitate their maintainability, understandability, and evolution. MathWorks recommends the use of three constructs for model “componentization” or decomposition: the Subsystem, Library, and Model Reference. However, a recently added construct introduced in Simulink R2014b, the Simulink Function, can also be used for this purpose, while also supporting information hiding due to the construct’s ability to be scoped and encapsulate data.
Technical Paper

On the Development of Optimal Hardware and Software Architectures for Propulsion Domain Control

2020-04-14
2020-01-1419
The modern automobile consists of a series of functional systems which implement the features of the vehicle and which are often connected via electronic networks. The function of each block in a system is often controlled or implemented by an electronic processor. In practice the existing architectures of both the network and processors is a consequence of the gradual introduction of electronics to a previously mechanical implementation and therefore tend to favour a flat network of cooperating peers and processors with hardware functions that are highly specific to the function required. New architectural approaches are now being evaluated to remove the limitations brought by the existing approach and in particular to address the changes in the propulsion system caused by the introduction of electric drive components.
Technical Paper

Recent Advances in Swelling Resistance of Graphene-Based Rubber Compounds

2020-04-14
2020-01-0769
Recently, graphene has attracted both academic and industrial interest because it can produce a dramatic improvement in properties at very low filler content. This review will focus on the latest studies and recent progress in the swelling resistance of rubber compounds due to the addition of graphene and its derivatives. This work will present the state-of-the-art in this subject area and will highlight the advantages and current limitations of the use of graphene for potential future researches.
Technical Paper

Parametric Representation of the Entire Pressure Drop Evolution during Particulate Filter Loading

2020-04-14
2020-01-1433
Improved understanding and compact descriptions of the pressure drop evolution of Particulate Filters (both for diesel and gasoline powered vehicles) are always in demand for intelligent implementations of exhaust emission system monitoring and control. In the present paper we revisit the loading process of a particulate filter focusing on a parametric description of the deep bed-to-cake transition in the light of recent progress in the understanding of soot deposit structure, growth dynamics and evolution. Combining experimental data, simulation models and information theoretic concepts we provide a closed-form representation of the entire evolution of pressure drop (from the initial clean state up to the evolving linear cake growth regime) parameterized in terms of the physical parameters of the system (filter and particle structure/geometry and flow properties).
Technical Paper

Comparative Analysis between a Barrier Discharge Igniter and a Streamer-Type Radio-Frequency Corona Igniter in an Optically Accessible Engine in Lean Operating Conditions

2020-04-14
2020-01-0276
Among plasma-assisted ignition technologies, the Radio-Frequency (RF) corona family represents an interesting solution for the ability to extend the engine operating range. These systems generate transient, non-thermal plasma, which is able to enhance the combustion onset by means of thermal, kinetic and transport effects. Streamer-type RF corona discharge, at about 1 MHz, ignites the air-fuel mixture in multiple filaments, resulting in many different flame kernels. The main issue of this system is that at high electrode voltage and low combustion chamber pressure a transition between streamer and arc easily occurs: in this case transient plasma benefits are lost. A barrier discharge igniter (BDI), supplied with the same RF energy input, instead, is more breakdown-resistant, so that voltage can be raised to higher levels. In this work, a streamer-type RF corona igniter and a BDI were tested in a single-cylinder optical engine fueled with gasoline.
Technical Paper

Impact of Ethane Enrichment on Diesel-Methane Dual-Fuel Combustion

2020-04-14
2020-01-0305
Over the past few years, the growing concerns about global warming and efforts to reduce engine-out emissions have made the dual-fuel (DF) engines more popular in marine and power industries. The use of natural gas as an alternative fuel in DF engines has both the environmental and economic advantages over the conventional diesel combustion. However, the misfire phenomenon at lean conditions limits the operating range of DF combustion and causes emissions of unburned hydrocarbon (UHC) and unburned methane (methane-slip) in the environment. The greenhouse effect of methane is considered 28 times greater than CO2 over a 100-year perspective, which raises concerns for the governments and marine engine manufacturers. In efforts to reduce the UHC and methane-slip from DF engines, this study discusses ethane enrichment of diesel-methane DF combustion in a full-metal single-cylinder research engine under lean condition (λGFB = ~2.0) while keeping the total-fuel energy rather constant.
Technical Paper

Anisotropic Material Damage Model of Randomly Oriented Thermoplastic Composites for Crash Simulation

2020-04-14
2020-01-1305
In this research, a material model was developed that has orthotropic properties with respect to in-plane damage to support finite element strength analysis of components manufactured from a randomly oriented long-fiber thermoplastic composite. This is a composite material with randomly oriented bundles of carbon fibers that are approximately one inch in length. A macroscopic characteristic of the material is isotropic in in-plane terms, but there are differences in the tension and compression damage properties. In consideration of these characteristics, a material model was developed in which the damage evolution rate is correlated with thermodynamic force and stress triaxiality. In-plane damage was assumed to be isotropic with respect to the elements. In order to validate this material model, the results from simulation and three-point bending tests of closed-hat-section beams were compared and found to present a close correlation.
Technical Paper

Thermal Behavior of an Electronics Compartment with Respect to Real Driving Conditions

2020-04-14
2020-01-1299
The reliability of electronic components is of increasing importance for further progress towards automated driving. Thermal aging processes such as electromigration is one factor that can negatively affect the reliability of electronics. The resulting failures depend on the thermal load of the components within the vehicle lifetime - called temperature collective - which is described by the temperature frequency distribution of the components. At present, endurance testing data are used to examine the temperature collective for electronic components in the late development stage. The use of numerical simulation tools within Vehicle Thermal Management (VTM) enables lifetime thermal prediction in the early development stage, but also represents challenges for the current VTM processes [1, 2]. Due to the changing focus from the underhood to numerous electronic compartments in vehicles, the number of simulation models has steadily increased.
Technical Paper

A Novel Supervisory Control and Analysis Approach for Hybrid Electric Vehicles

2020-04-14
2020-01-1192
There are many methods developed over the past decade to solve the problem of energy management control for hybrid electric vehicles. A novel method is introduced in this paper to address the same problem which reduces the problem to a set of physical equations and maps. In simple terms, this method directly calculates the actual cost or savings in fuel energy from the generation or usage of electric energy. It also calculates the local optimum electric power that yields higher electric fuel savings (EFS) or lower electric fuel cost (EFC) in the fuel energy that is spent for driving the vehicle (which in general does not take the system to the lowest engine Brake Specific Fuel Consumption (BSFC)). Based on this approach, a control algorithm is developed which attempts to approach the global optimum over a drive cycle.
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