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Training / Education

Applying DO-254 for Avionics Hardware Development and Certification

2024-11-20
This basic course introduces the intent of the DO-254 standard for commercial avionics hardware development. The content will cover many aspects of avionic hardware including, aircraft safety, systems, hardware planning, requirements, design, implementation, and testing. Participants will learn industry-best practices for real-world hardware development, common DO-254 mistakes and how to prevent them, and how to minimize risks and costs while maximizing hardware quality.
Training / Education

Development and Practice of Airborne Electronic Hardware Based on DO-254

2024-08-27
This course is offered in China only and presented in Mandarin Chinese. The course materials are bilingual (English and Chinese). Participants in this course comprehensive understanding of the DO-254 standard including how the development of airborne electronic hardware (AEH) and the development of the aircraft system are related. It addresses the key objectives, activities, and generated data of the AEH lifecycle and presents common problems in the application of DO-254 and how to prevent them. This course also includes current AEH certification requirements and interprets some of the difficulties in gaining compliance approval.
Training / Education

DO-326A and ED-202A An Introduction to the New and Mandatory Aviation Cyber-Security Essentials

2024-07-29
This course will introduce participants to industry best practices for real-world aviation cyber-security risk-assessment, development & assurance. Participants will learn the information necessary to help minimize DO-326/ED-202-set compliance risks and costs, while also optimizing cyber-security levels for the development, deployment and in-service phases Topics such as aircraft security aspects of safety, systems-approach to security, security planning, the airworthiness security process, and security effectiveness assurance will be covered.
Technical Paper

Reduction of Flow-induced Noise in Refrigeration Cycles

2024-07-02
2024-01-2972
In electrified vehicles, auxiliary units can be a dominant source of noise, one of which is the re-frigerant scroll compressor. Compared to vehicles with combustion engines, e-vehicles require larger refrigerant compressors, as in addition to the interior, also the battery and the electric motors have to be cooled. Currently, scroll compressors are widely used in the automotive industry, which generate one pressure pulse per revolution due to their discontinuous compression principle. This results in speed-dependent pressure fluctuations as well as higher-harmonic pulsations that arise from reflections. These fluctuations spread through the refrigeration circuit and cause the vibration excitation of refrigerant lines and heat exchangers. The sound transmission path in the air con-ditioning heat exchanger integrated in the dashboard is particularly critical. Various silencer con-figurations can be used to dampen these pulsations.
Technical Paper

Low NOx Emissions Performance after 800,000 Miles Aging Using CDA and an Electric Heater

2024-07-02
2024-01-3011
Engine and aftertreatment solutions have been identified to meet the upcoming ultra-low NOX regulations on heavy duty vehicles in the United States and Europe. These standards will require changes to current conventional aftertreatment systems for dealing with low exhaust temperature scenarios while increasing the useful life of the engine and aftertreatment system. Previous studies have shown feasibility of meeting the US EPA and California Air Resource Board (CARB) requirements. This work includes a 15L diesel engine equipped with cylinder deactivation (CDA) and an aftertreatment system that was fully DAAAC aged to 800,000 miles. The aftertreatment system includes an e-heater (electric heater), light-off Selective Catalytic Reduction (LO-SCR) followed by a primary aftertreatment system containing a DPF and SCR.
Technical Paper

Software-supported Processes for Aerodynamic Homologation of Vehicles

2024-07-02
2024-01-3004
Homologation is an important process in vehicle development and aerodynamics a main data contributor. The process is heavily interconnected: Production planning defines the available assemblies. Construction defines their parts and features. Sales defines the assemblies offered in different markets, where Legislation defines the rules applicable to homologation. Control engineers define the behavior of active, aerodynamically relevant components. Wind tunnels are the main test tool for the homologation, accompanied by surface-area measurement systems. Mechanics support these test operations. The prototype management provides test vehicles, while parts come from various production and prototyping sources and are stored and commissioned by logistics. Several phases of this complex process share the same context: Production timelines for assemblies and parts for each chassis-engine package define which drag coefficients or drag coefficient contributions shall be determined.
Technical Paper

Impact of AdBlue Composition and Water Purity on Particle Number Increase

2024-07-02
2024-01-3012
Previous studies have shown that dosing AdBlue into the exhaust system of diesel engines to reduce nitrogen oxides can lead to an increase in the number of particles (PN). In addition to the influencing factors of exhaust gas temperature, exhaust gas mass flow and dosing quantity, the dosed medium itself (AdBlue) is not considered as a possible influence due to its regulation in ISO standard 22241. However, as the standard specifies limit value ranges for the individual regulated properties and components for newly sold AdBlue, in reality there is still some margin in the composition. This paper investigates the particle number increase due to AdBlue dosing using several CPCs. The increase in PN is determined by measuring the number of particles after DPF and thus directly before dosing as well as tailpipe. Several AdBlue products from different sources and countries are measured and their composition is also analyzed with regard to the limit values regulated in the standard.
Training / Education

Bridging the Gap What You Need to Know About the Revised ARP4761A

2024-06-21
The cost of this introductory course can be applied to the cost of the full courses: C2301, ARP4754B Guidelines for Development of Civil Aircraft and Systems C2302, ARP4761A Guidelines and Methods of Performing the Safety Assessment for Certification of Civil Aircraft This short course is a high-level introduction to the revised SAE standard ARP4761A and its application of the guidelines of practice for aircraft and systems safety assessment.
Training / Education

Bridging the Gap What You Need to Know About the Revised ARP4754B

2024-06-20
The cost of this introductory course can be applied to the cost of the full courses: C2301, ARP4754B Guidelines for Development of Civil Aircraft and Systems C2302, ARP4761A Guidelines and Methods of Performing the Safety Assessment for Certification of Civil Aircraft This short course is a high-level introduction to the revised SAE standard ARP4754B and its guidelines of practice for aircraft and systems development.
Technical Paper

Transient Numerical Analysis of a Dissipative Expansion Chamber Muffler

2024-06-12
2024-01-2935
Expansion chamber mufflers are commonly applied to reduce noise in HVAC. Dissipative materials, such as microperforated plates (MPPs), are often applied to achieve a more broadband mitigation effect. Such mufflers are typically characterized in the frequency domain, assuming time-harmonic excitation. From a computational point of view, transient analyses are more challenging. A transformation of the equivalent fluid model or impedance boundary conditions into the time domain induces convolution integrals. We apply the recently proposed finite element formulation of a time domain equivalent fluid (TDEF) model to simulate the transient response of dissipative acoustic media to arbitrary unsteady excitation. As most time domain approaches, the formulation relies on approximating the frequency-dependent equivalent fluid parameters by a sum of rational functions composed of real-valued or complex-conjugated poles.
Technical Paper

Experimental and Simulation Study of Zero Flow Impact on Hybrid Vehicle Emissions

2024-06-12
2024-37-0036
Combustion engines in hybrid vehicles turn on and off several times during a typical passenger car trip. Each engine restart may pose a risk of excessive tailpipe emissions in real-drive conditions if the after-treatment system fails to maintain an adequate temperature level during zero flow. In view of the tightening worldwide tailpipe emissions standards and real-world conformity requirements, it is important to detect and resolve such risks via cost-effective engineering tools relying on accurate 3d analysis of the thermal and chemical behavior of exhaust systems. In this work, we present a series of experiments to examine the impact of zero-flow duration on the exhaust system cooling and subsequent emissions risk. We also present a catalyst model calibrated to predict the 3d thermal and chemical behavior under normal and zero flow conditions. Particular emphasis is given to the phenomena of free convection and thermal radiation dominating the heat transfer at zero flow.
Technical Paper

Effect of Dithering on post-catalyst exhaust gas composition and on short time regeneration of deactivated PdO/Al2O3 catalysts under real engine conditions

2024-06-12
2024-37-0002
Fossil fuels such as natural gas used in engines still play the most important role worldwide despite such measures as the German energy transition which however is also exacerbating climate change as a result of carbon dioxide emissions. One way of reducing carbon dioxide emissions is the choice of energy sources and with it a more favourable chemical composition. Natural gas, for instance, which consist mainly of methane, has the highest hydrogen to carbon ratio of all hydrocarbons, which means that carbon dioxide emissions can be reduced by up to 35% when replacing diesel with natural gas. Although natural gas engines show an overall low CO2 and pollutant emissions level, methane slip due to incomplete combustion occurs, causing methane emissions with a more than 20 higher global warming potential than CO2.
Technical Paper

Acceleration of Fast-SCR Reactions by Eliminating “The Ammonia Blocking Effect”

2024-06-12
2024-37-0001
The recent and future trends of energy for heavy-duty vehicles are considered e-fuel, H2, and electricity, and the Selective Catalytic Reduction (SCR) system is necessary for achieving the goals of zero-emission internal combustion engines that use e-fuel and H2 as a fuel. The Japanese automotive industry uses a Cu-zeolite based SCR catalyst since Vanadium is designated as a specific chemical substance, which the Ministry of Environment prohibits its release into the atmosphere. This study attempted purification rate improvement by controlling the NH3 supply with a mini-reactor and by simulated exhaust gas. Specifically, the experiment was done by examining the effect of the pulse amplitude, frequency, and duty ratio on the purification rate by supplying the NH3 pulse injection to the test piece Cu-chabazite catalyst. Additionally, the results of the reactor experiment were validated by numerical simulation considering the detailed surface reaction processes on the catalyst.
Training / Education

DO-178C Advanced Training

2024-06-12
This course is offered in China only and presented in Mandarin Chinese. The course materials are bilingual (English and Chinese). Participants deepen the understanding of the standard and build on how software engineers, inspectors, and DERs can comply with the standard's objectives. Practitioners engage with the implications and rationales of DO-178C in order to effectively tackle real worked applications.
Training / Education

FAA Part 21 Certification Procedures for Products and Parts

2024-06-06
The aerospace industry is hinged around compliance with Part 21; however, comprehension of Part 21 and its role in civil certification is challenging. This course is designed to provide participants with an understanding of the processes that encompass aircraft certification, including compliance with FARs, certification procedures and post certification responsibilities. It is also intended to introduce participants to the many regulatory issues upon which companies make business decisions that can be derailed by failing to see the part 21 implications.
Training / Education

Automotive Cybersecurity Certification Level Two

2024-06-03
This course has been developed in cooperation with TÜV SÜD. The certification concept behind the training comprises a multi-stage qualification and is characterized by a high level of practical bearing. The focus of this training is on the cybersecurity lifecycle for automotive products. In addition to a brief refresher on the content of the standard, important aspects of ISO/SAE 21434 that play an important role along the automotive lifecycle are discussed in detail. Starting with the topic "Culture & Competence", through cybersecurity planning to audits and assessments and post-development activities.
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