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Back in the first two decades of automobile development, electric propulsion was a serious competitor for the internal combustion engine. Electrically-propelled vehicles, however, soon proved unable to satisfy users' increasing performance demands in terms of range, acceleration, top speed and hill-climbing, together with such factors as operating life, initial purchase price, running costs and reliability. Engineers investigating electric propulsion today face precisely the same unwelcome legacy as their predecessors, despite many and varied attempts in the meantime to improve the components of the electric vehicle's drive system (energy storage device, motors, controller). Progress in battery development, particularly in the case of the NaS system, has nevertheless enabled us at least partly to overcome the previous problems associated with electric drive systems, though it cannot be claimed that all obstacles to its commercial application have been eliminated as yet.

Over the next decades to come, fossil fuel powered Internal Combustion Engines (ICE) will still constitute the major powertrains for land transport. Therefore, their impact on the global and local pollution and on the use of natural resources should be minimized. To this end, an extensive fundamental and practical study was performed to evaluate the potential benefits of simultaneously co-optimizing the system fuel-and-engine using diesel as an example. It will be clearly shown that the still unused co-optimizing of the system fuel-and-engine (including advanced exhaust after-treatment) as a single entity is a must for enabling cleaner future road transport by cleaner fuels since there are large, still unexploited potentials for improvements in road fuels which will provide major reductions in pollutant emissions both in vehicles already in the field and even more so in future dedicated vehicles.

This paper describes how Fluorescent Penetrant Inspection (FPI) was used in the past, how it is used now and how it will be used in the future. The United States Air Force (USAF) and Pratt & Whitney (P&W) now use a fully-automated FPI process with manual visual inspection. With direction and funding provided by the USAF/Aeronautical System Center (ASC), these fully-automated FPI processors, located at Kelly Air Force Base in San Antonio, Texas were developed, manufactured, installed, qualified and put into operation by Pratt & Whitney. This paper will cover the following: the Qualification and Acceptance Tests which include test objectives, test articles, test facility, test equipment, test results, and training.

In order to avoid the undesired side effect of water condensation occurring under special environment conditions in modern xenon lamps several modifications of the serial automotive headlamps were suggested. The suggestions consist of a) desired leakage in the cover, b) anti-fog coating and c) integrated ventilation tube. These strategies were tested using two types of serial head lamps applying a condensation cycle for the simulation of the urban condition. During this condensation cycle the thermodynamic parameters, like relative air humidity and temperature, were measured at different places in the head lamp and as function of time. The modification with the integrated ventilation tube is able to improve the serial head lamp significantly. The improvement in terms of water condensation for the modification using anti-fog coating depends from the number of cooling cycles.

This paper describes Pratt &Whitney's pioneering work in “constrained dynamic inversion,” a control algorithm architecture for multivariable systems that must operate tight to limits. A hallmark of gas turbine control is the prevalence and fundamental importance of tightly holding limits. When constrained dynamic inversion is applied to gas turbine systems control, this algorithm enables operation closer to physical and operational limits, while also providing faster and more precise responses. In addition to more fully exploiting systems physical capabilities, this architecture provides for the independent and finely coordinated control of system variables-of-interest even when each effector affects all variables. A distinctive feature of this algorithm is that it can be implemented on state of the art controllers at update rates consistent with vehicle control.

Over the past few decades, advanced methods have been developed for the analysis of digital systems using mathematical reasoning, i.e., formal logic. These methods are supported by sophisticated software tools that can be used to perform analysis far beyond what is practically achievable using “paper and pencil” analysis. In December 2011, RTCA published RTCA DO-178C [1] along with a set of technical supplements including RTCA DO-333 [2] which provides guidance on the use of formal methods towards the certification of airborne software. Such methods have the potential to reduce the cost of verification by using formal analysis instead of conventional test-based methods to produce a portion of the verification evidence required for certification.

This paper is the third in the series of documents designed to record the progress on the SAE Plug-in Electric Vehicle (PEV) communication task force. The initial paper (2010-01-0837) introduced utility communications (J2836/1™ & J2847/1) and how the SAE task force interfaced with other organizations. The second paper (2011-01-0866) focused on the next steps of the utility requirements and added DC charging (J2836/2™ & J2847/2) along with initial effort for Reverse Power Flow (J2836/3™ & J2847/3). This paper continues with the following: 1. Completion of DC charging's 1st step publication of J2836/2™ & J2847/2. 2. Completion of 1st step of communication requirements as it relates to PowerLine Carrier (PLC) captured in J2931/1. This leads to testing of PLC products for Utility and DC charging messages using EPRI's test plan and schedule. 3. Progress for PEV communications interoperability in J2953/1.

Automatic Crash Notification (ACN) technology provides an opportunity to rapidly transmit crash characteristics to emergency care providers in order to improve timeliness and quality of care provided to occupants in the post crash phase. This study evaluated the relative value of crash attributes in providing useful information to assist in the identification of crashes where occupants may be seriously injured. This identification includes an indication of whether a crash is likely to require a level of emergency response with higher priority than is needed for most crashes reported by ACN Systems. The ability to predict serious injury using groupings of variables has been determined. In this way, the consequence of not transmitting each variable can be estimated. In addition, the incremental benefit of voice communication is shown.

This paper provides an insight into how the introduction and implementation of the blending borescope used to perform on-wing blending of compressor blades on Pratt & Whitney (P&W) Engines has resulted in significant savings. It describes the following: Commercial statistics and savings; Military statistics and potential savings; P&W maintenance team; What is on-wing blending; The capabilities of on-wing blending; The contents of a typical blending borescope inspection kit; Test results; Measurement of Foreign Objects Damage (FOD); Installation of the equipment; How to blend FOD; How to measure the repair and observe how the equipment provides precise results; How to polish the repair. Typical commercial cost savings for blending assembled compressors are in the order of $360,000.00 per event, compared with engine teardown cost.

The intent of a balanced engine design process is to satisfy all systems requirements including operability, performance and durability. Due to the complexity of the trade-off process of the various metrics it is possible that system improvements may be required after a turbofan engine enters production. Also, in the case of derivative engines, configured for increased performance, the flowpath aerodynamics may be challenged and may have to be examined to ensure there is no flow field anomaly. By incorporating special diagnostic aero instrumentation at the earliest opportunity any required operability improvement can be identified and corrective action taken. The paper first delineates the component matching challenges of twin spool mixed flow turbofan engines. Then it discusses investigation of various potential destabilizing influences.

This technical paper presents the author's recommended approach to one aspect of managing flight safety - conducting Safety Risk Analyses (SRA) on in-service problems that may threaten flight safety. The author did not develop this statistically based approach for assessing the risk of future events, but has helped to improve it and highly endorses it. In conducting a safety risk analysis, the analyst might decide to perform a “quick” SRA and will need a minimal amount of information that will show the relative level of flight safety risk. When the analyst decides a complete safety risk analysis is needed, the possible approaches and level of details included in the SRA can vary greatly from company to company.

A Distributed Engine Control Working Group (DECWG) consisting of the Department of Defense (DoD), the National Aeronautics and Space Administration (NASA)- Glenn Research Center (GRC) and industry has been formed to examine the current and future requirements of propulsion engine systems. The scope of this study will include an assessment of the paradigm shift from centralized engine control architecture to an architecture based on distributed control utilizing open system standards. Included will be a description of the work begun in the 1990's, which continues today, followed by the identification of the remaining technical challenges which present barriers to on-engine distributed control.

BMW has undertaken a comprehensive program including laboratory simulation rig tests, engine dynamometer and fleet evaluations to evaluate the influence of mechanical and fuel variables on induction system deposits in modern port fuel injected (PFI) spark ignition engines. The primary focus of the program has been the deposit buildup on intake valves (IVD) and associated driveability impacts. Initial investigations of engine modifications yielded only marginal improvements relative to deposit build-up and, therefore this led to investigations of the effect of gasolines and additives. Fuel quality, type, quantity of additives and alcohol content have all been found to be major contributing factors to intake valve deposition. In addition, intake valve deposit weight has been directly related to warm-up phase driveability concerns using a newly developed driveability procedure.

The idea of keeping a vehicle safe and secure throughout its whole life cycle, as well as having the opportunity to add functionality after initial delivery, is the key motivation behind automotive software updates. Today, safety or security issues that appear after vehicle delivery need to be resolved by starting a recall campaign. These campaigns require the vehicle user to visit a car repair workshop to get an update. Over The Air (OTA) software updates, being location-independent, can pave the way for higher update frequencies and more efficiency regarding customer satisfaction, resource consumption as well as safety and security. In this paper we analyze requirements for OTA software updates phrased in various standards and regulations as well as in existing development and type approval processes. Prevailing challenges for OTA updates are extracted to identify necessary activities and artifacts within the procedure.

This paper summarises the potential for the use of a gasoline direct injection engine for fuel economy benefits. Various engine technologies are compared for the greatest reduction in fuel consumption at the steady state point 2000rpm/2 bar. This is an important driving point in the EU cycle. The direct injection engine when used in an unthrottled lean stratified mode shows the greatest potential. Calculations show a fuel economy of a middle class vehicle can be increased by 12% using a DI over the EU cycle. The catalytic aftertreatment system is discussed and it is concluded that a close coupled pre-catalyst, a NOx trap and double injection are a good overall solution for the minimisation of exhaust gas emissions from a DI engine.

In the present study, an experimental investigation was conducted to characterize a hot-air-based anti-/de-icing system for the icing protection of aero-engine inlet guide vanes(IGVs). The experimental study was conducted in a unique icing research tunnel available at Iowa State University (i.e., ISU-IRT). A hollowed IGV model embedded with U-shaped hot-air flowing conduit was designed and manufactured for the experimental investigations. During the experiments, while a high-speed imaging system was used to record the dynamic ice accretion or anti-/de-icing process over the surface of the IGV model for the test cases without and with the hot-air supply system being turned on, the corresponding surface temperature distributions on the IGV model were measured quantitatively by using a row of embedded thermocouples.

A through-flow based Monte Carlo particle trajectory simulation is used to calculate the ice crystal paths in the low pressure compressor of a high bypass ratio turbofan engine. The simulation includes a statistical ice particle breakup model due to impact on the engine surfaces. Stage-by-stage ice water content, particle size and particle velocity distributions are generated at multiple flight conditions and engine power conditions. The majority of the ice particle breakup occurs in the fan and first LPC stage. The local ice water content (IWC) within LPC is much higher than the ambient conditions due to scoop effects, centrifuging and flow-path curvature. Also the ice particles approach the stators at lower incidence angles than the air flow. The simulation results prompt the need to revisit the approach for properly setting up boundary conditions for component or cascade testing.

To reduce vehicle development cycles it is necessary to perform numerical durability analyses in an early development phase. Typically there is no physical prototype available at that time hence there are no measured data, either from the proving ground or from test rigs. This paper presents an alternative method to predict the required loads. Using Multi-Body Simulation (MBS), the loads prediction process is performed for an unconstrained vehicle, which means that vehicle body position and orientation are allowed to change. Of particular interest are the time series of the loads acting at components of the front-and the rear-suspension, as well as on the body structure of the vehicle. For the loads prediction BMW uses the so called Hybrid-Road-Approach developed by LMS. After an initial pilot project demonstrating that approach's feasibility and potential, the project presented below is the first run of that approach by BMW in their productive environment.

Engine module performance trending and engine system anomaly detection and identification are core capabilities for any engine Condition Based Maintenance system. The genesis of on-condition monitoring can be traced back nearly 4 decades, and a methodology known as Gas Path Analysis (GPA) has played a pivotal role in its evolution. GPA is a general method that assesses and quantifies changes in the underlying performance of the major modules of the engine (compressors and turbines) which directly affect performance changes of interest such as fuel consumption, power availability, compressor surge margins, and the like. This approach has the added benefit in that it enables anomaly detection and identification of many engine system accessory faults (e.g., variable stator vanes, handling and customer bleeds, sensor biases and drift). Legacy GPA has been confined to off-board analysis of snapshot data averaged over a stable flight conditions when the engine is in steady state operation.