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Technical Paper
2014-09-28
Jaroslaw Grochowicz, Carlos Agudelo, Shanglei Li, Harald Abendroth, Karl-Heinz Wollenweber, Achim Reich
The efforts of the ISO “Test Variability Task Force” have been aimed at improving the understanding and at reducing brake dynamometer performance test variability. In addition, dynamometer test results have been compared and correlated to vehicle testing. This paper focuses on assessing friction levels, friction coefficient sensitivity, and repeatability under ECE, GB, ISO, JASO, and SAE laboratory performance tests. With multiple companies (or programs) developing and assessing the friction coefficient and friction behavior under different methods, it is inevitable to avoid conflicts of performance requirements or lack of reproducibility or correlation of test results under different test methods. In order to provide an evaluation consistent with previous phases of the Task Force activities, the same brake corner assembly and same friction material is used for this study. The study is comprised of three main steps: (a) Conducting tests under several test procedures: • ISO 26867:2009 — Friction Behaviour Assessment for Automotive Brake Systems (two samples) • SAE J2522:2013 — Dynamometer Global Brake Effectiveness (two samples) • SAE J2784:2009 — FMVSS Inertia Dynamometer Test Procedure for Vehicles Below 4 540 Kg GVWR (two samples) • JASO C406:2000 — Passenger Car — Dynamometer Test Procedures (two samples) • ECE R90-02:2013-Annex 9 – Part A— Determination of friction behaviour by machine testing (three samples) • SAE J661:2012 — Brake Lining Quality Control Test Procedure (five samples) • GB 5763:2008 — Brake Linings for Automobiles (TBD samples) all dynamometer tests were conducted using the same inertia dynamometer to eliminate the reproducibility (dyno-to-dyno) component in the total variability evaluation.
Technical Paper
2014-09-28
Qiang wang, Gang Qi, Guangrong Zhang, Xinyu Pu
A brake durability experiment method is proposed to simulate the brake durability vehicle road test. Brake shudder and noise will be happened in brake durability test. Brake shudder is difficult to address with lots of constituents, such as assembly run out, component stiffness, lining characteristic, thermal and corrosion, and so on. There are some test procedures to predict brake thermal roughness and pad cleaning corrosion performance to prevent brake shudder. The brake durability vehicle road test is performed to run brake NVH and wear, such as Mojacar in Spain and Huangshan test in China. The brake energy intensity and road excitation are the significant factors for brake rotor thickness variation generation causing the brake shudder in public road test. The study is focused on brake wear depending on brake energy intensity and brake temperature ,brake rotor TV generation induced by wear to simulate the brake durability road test. Brake durability road test was performed to obtain braking initial velocity, temperature, deceleration and brake pad wear during the test.
Technical Paper
2014-09-16
Martin Bradish
Author Name (s): William .D. Ivancic, Obed S. Sands, Casey J. Bakula, Daniel R. Oldham, Ted Wright, Martin A. Bradish, Joseph M. Klebau Mailing Address: Martin Bradish, NASA Glenn Research Center, 21000 Brookpark Road, MS 86-5, Cleveland, Ohio 44135 USA Telephone Number: (216) 433-3848 Fax Number: (216) 433-6382 eMail Address: martin.a.bradish@nasa.gov This paper summarizes the Power, Avionics and Software (PAS) 1.0 subsystem integration testing and test results that occurred in August and September of 2013. This paper covers the capabilities of each PAS assembly to meet integration test objectives for non-safety critical, non-flight, non-human-rated hardware and software development. This test report is the outcome of the first integration of the PAS subsystem and is meant to provide data for subsequent designs, development and testing of the future PAS subsystems. The two main objectives were to assess the ability of the PAS assemblies’ to exchange messages and to perform audio tests of both inbound and outbound channels.
Technical Paper
2014-09-16
Andreas Himmler
Test systems for aircraft systems are crucial for reaching and ensuring the safety of passengers, crew and other persons in air traffic. In the past, the requirements to be met by aircraft systems regarding safety, environmental friendliness, reliability and comfort have already become significantly more extensive and complex. This trend will continue in the foreseeable future. In addition to the requirements on the aircraft systems, with each aircraft program, the requirements on the test systems for electronic control units (ECUs) has also increased, as both the number of systems to be tested and their complexity has grown. As a result, the number of necessary test systems for ECUs has also increased with each aircraft program. At the same time, each aircraft program causes an increase in the number of simulation models necessary for the tests. To make the development of complex aircraft systems manageable and economical, tests must be performed as early as possible in the development process.
Technical Paper
2014-09-16
Javier A. Parrilla
Current industry trends demonstrate aircraft electrification will be part of future platforms in order to achieve higher levels of efficiency in various vehicle level sub-systems. However, electrification requires a substantial change in aircraft design that is not suitable for re-winged or re-engined applications as some aircraft manufacturers are opting for today. Thermal limits arise as engine cores progressively get smaller and hotter to improve overall engine efficiency, while legacy systems still demand a substantial amount of pneumatic, hydraulic and electric power extraction. The environmental control system (ECS) provides pressurization, ventilation and air conditioning in commercial aircraft, making it the main heat sink for all aircraft loads with exception of the engine. To mitigate the architecture thermal limits in an efficient manner, the form in which the ECS interacts with the engine will have to be enhanced as to reduce the overall energy consumed and achieve an energy optimized solution.
Technical Paper
2014-09-16
Jace Allen
In the last few years, we have seen a tremendous increase in the rise in product complexity due to advances in technology and aircraft system functionality enhancement. The Model-based Design (MBD) process has helped manage the complexity of these systems while making product development faster by bringing more effective tools and methods to the entire process. Developing software using MBD has required extensive, sophisticated tool-chains that allow for efficient rapid controls prototyping, automatic code generation, and advanced validation and verification techniques using MIL, SIL and HIL for both component testing and integration testing. However, the MBD process leads to generation of large volumes of data artifacts and work-products throughout the V-Cycle of development. The various components of these environments, from models to parameters to tests, can be inundating, and variants and versions of these artifacts lead to even larger amounts of data. These artifacts have traditionally been managed with Configuration Management systems and Product Lifecycle Management (PLM) tools, but the process of managing the links and information about this data (metadata) has been a difficult task for many companies.
Technical Paper
2014-09-16
Riko Bornholdt, Frank Thielecke
The current delay of the successors for the present civil short- and long-range aircraft models leads to the focus on retrofit strategies on the one hand. On the other hand due to the additional time frame for the development of the projected successors new degrees of freedom can be exploited. In both cases new potential can be gained by challenging the existing requirements, which restrict aircraft system innovations. Reconsidering the functions and their allocation to specific systems could lead to beneficial architecture concepts. Furthermore analyzing the independencies between the systems and dissolving the system specific development paradigm could allow the exploitation of synergies and expose room of improvement. The described shift in the design approach leads to the need for new methodologies for integrated system architecture design, which consider the changed constraints and capitalize the gained potentials. The paper and the corresponding presentation will cover a methodology guiding the engineer through the successive process of aircraft system architecture design.
Technical Paper
2014-09-16
Tim C. O'Connell, Kevin McCarthy, Andrew Paquette, David McCormick, Paul Pigg, Peter T. Lamm
Validation of models is a critical component of Model Based Design (MBD). Without validation, the accuracy of the models is not certain, so the decisions made with those models may not be based on the best information. The Integrated Vehicle Energy Technology (INVENT) program is planning a series of hardware experiments that will be used to validate a large set of integrated models. While the task of validating such a large number of interacting models is daunting, it provides an excellent opportunity to test the limits of MBD. Model validation can take places in many ways, from direct model parameter measurement, to inferred measurements to dynamic signal comparisons. In addition, for complex systems like the ones being tested on INVENT, validation can happen at many levels, from individual unit construction all the way to integrated testing. A process for coordinating these varied validation efforts across multiple participants is needed. For INVENT, a plan to implement all the aspects of validation listed above has been created.
Technical Paper
2014-09-16
Tim C. O'Connell, Kevin McCarthy, Andrew Paquette, David McCormick, Paul Pigg, Peter T. Lamm
ABSTRACT
Technical Paper
2014-09-16
Teresa Donateo, Maria Grazia De Giorgi, Antonio Ficarella, Elisabetta Argentieri, Elena Rizzo
The aim of the present investigation is the implementation of a Matlab/Simulink environment to assess the performance (thrust, specific fuel consumption, aircraft/engine mass, cost, etc.) and environmental impact (greenhouse and pollutant emissions) of conventional and more electric aircrafts. In particular, the benefits of adopting more electric solutions for either aircrafts at given missions specifications can be evaluated. Each component is modeled as a black box that receives input (in terms of mass flow and energy) from the previous component and send its output variables to the next one after a balance of mass and energy content. The software includes a design workflow for the input of the aircraft specification, the choice of the architecture (e.g. series or parallel) and the specification of each component including energy converter (piston engine, turboprop, turbojet, fuel cell, etc.), energy storage systems (batteries, supercapacitors), auxiliaries and secondary power systems.
Technical Paper
2014-09-16
Jennifer C. Shaw, Patrick Norman, Stuart Galloway, Graeme Burt
In order for the Subsonic Fixed Wing (SFW) N+3 initiative goals to be realised, aircraft subsystems and airframes need to be optimised for both energy efficiency and operational effectiveness. Concepts and designs proposed to achieve these goals are expected to lead to a significant departure from the modern day state of the art in electrical system architectures, most notably with the inclusion of electrically driven propulsors. Such Turboelectric Distributed Propulsion (TeDP) systems place a much greater emphasis on the electrical system for safe and efficient flight. A key distinguishing factor between current more-electric and TeDP network architecture designs is the power level at which critical loads must be supplied, specifically the supply to high power propulsion motors in TeDP systems must provide a similar level of reliability to that of traditional low power critical loads (such as avionics) in present day aircraft. Necessary to achieving supply targets for current systems is the use of battery backup; however, the provision of sustained operability through additional supply for high power loads, either through dedicated generators or bulk energy storage, is inefficient in terms of weight.
Technical Paper
2014-09-16
Jon Hagar
System testing can, in part, be defined as the application of concepts as an attempt to demonstrate that the implementation DOES NOT meet its intended use. Unfortunately many industry test efforts only show that a system meets requirements which, while necessary, is not sufficient to fully address a product's system testing. Many managers, engineers, and testers are not familiar with the wide variety of concepts and standards available for system and software testing-many of which can actually save projects money. Standards can offer a wealth of knowledge and can prove their value in any given product. This presentation offers a review of concepts and standards that many testers will find valuable including: - Math-based techniques which apply combinatorial, statistical, Design of Experiments (DOE), or domain-based concepts - Attack-based testing which focuses on common industry error taxonomies - Independent model-based testing using tooling and standards - New standards-driven testing to address verification and validation (V&V), testing, and documentation that few test teams are aware of.
Technical Paper
2014-09-16
Karen Davies, Patrick Norman, Catherine Jones, Stuart Galloway, Graeme Burt
In an attempt to reduce NOx and noise emissions and improve overall fuel efficiency of future generation aircraft, Turboelectric Distributed Propulsion (TeDP) is being considered as a novel means of providing aircraft thrust. TeDP designs proposed to date have comprised a fully superconducting, and typically DC, network in which a number of generators provide power to multiple propulsors distributed across the aircraft via a complex arrangement of parallel redundant busbars and feeders. As such, the electrical network is critical to the safety of the aircraft and in order to attain the required levels of reliability, effective protection systems, tuned specifically to the superconducting parameters of the network, must be devised. Under normal operating conditions, superconducting materials have zero resistance, and superconducting cables have a lower mutual inductance than that of conventional cables. Compared with conventional networks, these parameters introduce less damping, leading to higher prospective fault currents and faster rates of fault development.
Technical Paper
2014-09-16
Christine Ross, Michael Armstrong, Mark Blackwelder, Catherine Jones, Patrick Norman, Steven Fletcher
The NASA N3-X blended-wing body with turboelectric distributed propulsion (TeDP) concept is being studied to achieve N3-X goals such as reduced noise, NOx emissions, and improved energy efficiency. The gas turbine engines are used to provide rotational energy to generators which convert this energy to electrical. The electrical power output of the generators is rectified and distributed as a DC system to an array of propulsor motors each with their own inverter. The electrical distribution system is superconducting in order to maximize its efficiency and increase the power density of all associated components. An aspect of this concept currently under study is the protection of the electrical distribution system for propulsion. The protection of a superconducting DC network poses unique electrical and thermal challenges due to low impedance of the superconductor and operation in the superconducting or quenched states. For a fixed TeDP electrical system architecture with fixed power ratings, several protection strategies are investigated.
Technical Paper
2014-09-16
Yamina Boughari, Ruxandra Botez, Georges Ghazi, Florian Theel
The main goal of the flight control system is to achieve good performances with acceptable flying qualities within the specified flight envelope and to ensure robustness for models variations. In this research, the Cessna Citation X aircraft linear model is presented using different flight conditions to cover the aircraft’s flight envelope, on which a robust controller is designed using H-infinity method optimized by two different heuristic algorithms. The optimal controller was used to reach satisfactory dynamic characteristics for the lateral stability control augmentation systems with respect to flying qualities requirements for the Cessna Citation X aircraft. The weighting functions of the H-infinity method were optimised by using both genetic and the differential evolution algorithms. The evolutionary algorithms here used have given very good results. These algorithms were used in this form for the first time to optimize H_infinity controllers on a business aircraft control, using both flying qualities requirements and robustness criterion as objective function and to avoid using algorithms which are computationally complicated.
Technical Paper
2014-09-16
Hidefumi Saito, Shoji Uryu, Norio Takahashi, Noriko Morioka, Hitoshi Oyori
In this study, we seek solution to energy optimization issue of Environmental Control System (ECS) for electric aircraft. Aircraft ECS must have three functions as pressurization, ventilation, and temperature control. Non-bleed ECS based on more electric aircraft makes it possible to distribute the three functions to equipment. Motor Driven Fresh Air Compressor (MDFAC) mainly takes charge of pressurization function and ventilation function, therefore selection of equipment for temperature control function is important. We select not Air Cycle System (ACS) but Vapor Cycle System (VCS) as the equipment for temperature control function, for minimization of energy consumption by higher Coefficient of Performance (COP). We try to clarify specifications, configuration and weight of the VCS suitable for the temperature control function of single aisle aircraft, which is a non-bleed type aircraft equipped with MDFACs. To keep increase of flight fuel consumption by additional weight negligible, weight and rated performance of the VCS are set as the same as those of the ACS.
Standard
2014-07-24
Scope—Traditional methods of photometry rely on the use of a goniometer to rotate the test item around two axes at right angles. This method is satisfactory for most situations but has certain disadvantages: a. Point-by-point measurements with a goniometer may be slow. With more advanced requirements, particularly for headlamps, where the entire beam pattern is of concern, isocandela measurements are becoming increasingly needed. Such testing can be very time consuming. b. For production quality assurance, the speed of a goniometer may not allow testing to keep pace with the production line if a large quantity of lamps must be sampled. c. High Intensity Discharge (HID) lamps are becoming commonly used. Such lamps are orientation sensitive, changing in both lumen output and intensity distribution when tilted. This can introduce significant inaccuracies in test results when testing is performed using a goniometer. There is a need for alternative test techniques which can achieve very high speed data acquisition, the capture of full isocandela distribution, and the elimination of lamp tilting.
WIP Standard
2014-07-22
A program, which ensures quality with the relevant standards shall be introduced for all on-line Stations where de-icing/anti-icing of aircraft on the ground is either normally carried out, or where local conditions may periodically lead to a requirement for airplcraft to be de-iced/anti-iced. Deficiencies, in regard to a Station's local de-icing/anti-icing procedures, shall be identified and subsequently actioned through this program, thereby ensuring that the required safety standards are maintained.
WIP Standard
2014-07-22
SPECIFICATION COVERS A TAPE STYLE DEVICE FOR REPAIRING LARGER SIZE PRIMARY WIRE.
Standard
2014-07-22
This SAE Aerospace Standard (AS) covers plain spherical bearings which are self-aligning and self-lubricating by utilizing polytetrafluoroethylene (PTFE) in a fabric composite or molded material that is bonded to the inner diameter surface of the race and when specified, to the bore diameter surface of the ball. These bearings are for use in the temperature range -65 to +325 °F (-54 to +163 °C).
Standard
2014-07-22
This AS describes a standard method for viscosity measurements of thickened (AMS1428) anti-icing fluids. Fluid manufacturers may publish alternate methods for their fluids. In case of conflicting results between the two methods, the manufacturer method takes precedence. To compare viscosities, exactly the same measurement elements (including spindle and container size) must have been used to obtain those viscosities.
WIP Standard
2014-07-18
This specification covers quality assurance sampling and testing procedures used to determine conformance to applicable specification requirements of carbon and low-alloy steel forgings.
WIP Standard
2014-07-15
This document specifies the procedure to be used for a manufacturer to certify the net power and torque rating of a production engine according to J1349 (Rev. 8/04) or the gross engine power of a production engine according to SAE J1995. Manufacturers who advertise their engine power and torque ratings as Certified to SAE J1349 or SAE J1995 shall follow this procedure. Certification of engine power and torque to J1349 or J1995 is voluntary, however, this power certification process is mandatory for those advertising power ratings as "Certified to SAE J1349".
WIP Standard
2014-07-14
This method is currently under development in the E-34C Lubricating Characteristics subcommittee as a technique to predict the micropitting performance of 5 cSt turbine oils. The PCS Instruments Micro pitting rig (MPR) is currently used by the Industry to look at both macro and micro pitting resistance of lubricating oils on gears and bearings. Using the test methods and profile developed from testing performed by Powertrib, and then further discussions between PCS Instruments (the instrument manufacturer) and the E-34C committee, a set of proposed test conditions have been agreed. Once the specimens have been manufactured, a small round robin is planned to look at repeatability and reproducibility.
Standard
2014-07-11
This document specifies that black is the only color that can be used for the insulator at the bottom of the base of T-1 and T-1 ¾ Flanged Base lamps.
Standard
2014-07-11
This specification covers minimum design and test requirements for aircraft tire inflation-deflation equipment for use on all types of aircraft. It shall be the responsibility of the airframe manufacturer to determine the compatibility of the requirement with the applicable aircraft and to specify requirements in excess of these minimums as necessary.
WIP Standard
2014-07-11
The purpose of this SAE Standard is to offer simplified and prioritized guidelines for collecting and preserving on-scene data related to motor vehicle accidents. It is intended that these guidelines improve the effectiveness of data collection, which will assist subsequent analysis and reconstruction of a particular incident. The document is to guide early data collectors whose objectives include documenting information related to the incident. it may be used by law enforcement personnel, safety officials, insurance adjusters and other interested parties. The document identifies categories of scene physical features that deteriorate relatively quickly and recomends documentation task priorities. Detailed methods of collecting data are not part of this document. However, some widely used methods are described in the references in Seciton 2.
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