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Technical Paper

175°C-Capable Thermoplastic Elastomers for Automotive Air Management and Sealing Applications

2007-11-28
2007-01-2576
Flexibility, oil resistance, and the need for heat resistance to 150°C-plus temperatures have traditionally limited automotive design engineers to two options - thermoset rubber or heat-shielding conventional thermoplastic elastomers (TPE). Both of these options present limitations in part design, the ability to consolidate the number of components in a part of assembly, and on total cost. This paper presents a class of high-performance, flexible thermoplastic elastomers based on dynamically vulcanized polyacrylate (ACM) elastomer dispersed in a continuous matrix of polyamide (PA) thermoplastic. These materials are capable of sustained heat resistance to 150°C and short-term heat resistance to 175°C, without requiring heat shielding. Recent advancements in blow molding and functional testing of the PA//ACM TPEs for automotive air management (ducts) and underhood sealing applications will be shown.
Technical Paper

4 Stroke Gasoline Engine Performance Optimization Using Statistical Techniques

2001-12-01
2001-01-1800
The engine designer has to find novel methods to optimize the engine efficiency faster as the engine development cycle is getting shortened due to the continuous growing market demands. Engine optimization involves fine tuning of the various engine parameters and conducting a large number of tests on actual engine test bed. In this paper, modern techniques that have been used to optimize a small 4stroke air-cooled engine performance have been described. The engine has been modelled using one-dimensional thermodynamic engine modelling software (AVL-BOOST). Design of experiments (DoE) tools have been used to optimize the engine variables. The input parameters form an orthogonal array of L27 matrix and the out put characteristics of the engine (responses) have been predicted by using BOOST software. This design matrix has been used to study and optimize thirteen factors in three levels (313).
Technical Paper

A CFD Multidimensional Approach to Hydraulic Components Design

2007-10-30
2007-01-4196
This paper presents a multidimensional approach to the hydraulic components design by means of an open-source fluid dynamics code. A preliminary study of a basic geometry was carried out by simulating the efflux of an incompressible fluid through circular pipes. Both laminar and turbulent conditions were analyzed and the influence of the grid resolution and modeling settings were investigated. A qualitative description of the internal flow-field distribution, and a quantitative comparison of pressure and velocity profiles along the pipe axis were used to asses the multidimensional open-source code capabilities. Moreover the results were compared with the experimental measurements available in literature and with the theoretical trends which can be found in well-known literature fundamentals (Hagen-Poiseuille theory and Nikuradse interpolation). Further comparison was performed by using a commercial CFD code.
Technical Paper

A Cooperative Airline Program to Evaluate Engine Parts Aging Effects on a Current Turbofan Engine Model

1970-02-01
700329
The contribution that aged hardware makes to performance deterioration is of interest to operators of JT3D turbofan powered aircraft since a significant percentage of these engines have exceeded 20,000 hr of operation. Recent studies involving numerous engine disassemblies, rebuild, and test cell runs reveal the most significant effects of aged hardware are the loss in high and/or low compressor stall margin; and, that a large number of parts must be replaced to realize a significant improvement in fuel consumption, with the exception of the reduction that can be obtained by controlling turbine seal clearances.
Standard

A GUIDE TO THE DEVELOPMENT OF A GROUND STATION FOR ENGINE CONDITION MONITORING

1994-02-01
HISTORICAL
AIR4175
An effective ground station is vital to the successful implementation of an EMS and is a fundamental part of the total monitoring system design. Unlike on-board processing systems which principally use data to indicate when engine maintenance is required, ground stations offer much greater processing power to analyse and manipulate EMS data more comprehensively for both maintenance and logistics purposes. This document reviews the main EMS functions and discusses the operating requirements which will determine the basic design of a ground station, including the interfaces with other maintenance or logistics systems. A brief discussion is also included on some of the more recent advances in EMS ground station technology which have been specifically developed to provide more effective diagnostic capabilities for gas turbine engines. Finally, this document addresses the program management requirements associated with the initial development and on-going support of a ground station.
Technical Paper

A Global Model for Steady State and Transient S.I. Engine Heat Transfer Studies

1996-02-01
960073
A global, systems-level model which characterizes the thermal behavior of internal combustion engines is described in this paper. Based on resistor-capacitor thermal networks, either steady-state or transient thermal simulations can be performed. A two-zone, quasi-dimensional spark-ignition engine simulation is used to determine in-cylinder gas temperature and convection coefficients. Engine heat fluxes and component temperatures can subsequently be predicted from specification of general engine dimensions, materials, and operating conditions. Emphasis has been placed on minimizing the number of model inputs and keeping them as simple as possible to make the model practical and useful as an early design tool. The success of the global model depends on properly scaling the general engine inputs to accurately model engine heat flow paths across families of engine designs. The development and validation of suitable, scalable submodels is described in detail in this paper.
Technical Paper

A Low Cost, Lightweight Solution for Soft Seamless Airbag Systems

2004-03-08
2004-01-1485
OEM and Tier One integrated suppliers are in constant search of cockpit system components that reduce the overall number of breaks across smooth surfaces. Traditionally, soft instrument panels with seamless airbag systems have required a separate airbag door and a tether or steel hinge mechanism to secure the door during a deployment. In addition, a scoring operation is necessary to ensure predictable, repeatable deployment characteristics. The purpose of this paper is to demonstrate the development and performance of a cost-effective soft instrument panel with a seamless airbag door that results in a reduced number of parts and a highly efficient manufacturing process. Because of the unique characteristics of this material, a cost-effective, lightweight solution to meet both styling requirements, as well as safety and performance criteria, can be attained.
Journal Article

A Model Generator for Simulation and Testing of RDCs

2011-10-18
2011-01-2636
Simulation of avionics equipment is essential due to the complex nature of its development and integration process. Throughout the development process, executable component models are used to demonstrate the feasibility and the compliance of the system design with respect to its functional requirements. In later development phases, there is the need for system integration tests where a mix of real and simulated equipment is used to verify the overall system behavior. Since Boeing 777 and Airbus A380 programs, IMA1 technology has entered several civil aircraft systems. In recent programs like Boeing 787 and Airbus A350 the number of IMA components has significantly increased. In this paper we present a simulation model for a new IMA component - the common Remote Data Concentrator (CRDC)2, which is developed by Thales-Diehl for the Airbus A350 XWB. Building simulation models of IMA components is in general a challenging task due to their complexity on both software and hardware level.
Technical Paper

A New Deutz Multifuel System

1972-02-01
720103
As manufacturers of air-cooled diesel engines, the company of Klöckner-Humboldt-Deutz (KHD) undertook the rather rapid development of a multifuel engine on the basis of a proved mass-produced, air-cooled unit. Being equal in output, this new engine had to run on all fuels and fuel mixtures obtainable at gasoline stations without any modifications being necessary. Preferably, it had to be produced by means of the same manufacturing facilities as the series engine and features a maximum number of identical parts. The solution to the problem involves supplementing the series engine with a high-tension ignition system employing a special spark plug in the direct vicinity of the injection nozzle. This spark plug can be subsequently installed following the rework of standard parts. By using the same basic setting of injection and ignition for all fuels, it is possible to attain absolutely knock-free combustion, with a gentle compression curve and a minimum of cyclic pressure variations.
Technical Paper

A Novel Transfer Path Analysis Method Delivering a Fast and Accurate Noise Contribution Assessment

2010-10-17
2010-36-0529
15 years of NVH applications make Transfer Path Analysis (TPA) appear a commodity tool. But despite the fact that TPA is today successfully used in a large variety of applications in automotive and mechanical industries, its main bottleneck remains the huge measurement time to build the full TPA model. This paper presents a new TPA method that provides a good compromise between path accuracy and measurement time. The method is also referred to as OPAX. The key idea of OPAX is the use of simplified parametric load models with limited number of model parameters. The main advantage of this is that one should measure only a small amount of FRF data to identify the operational loads. This drastically reduces measurement time and efforts. In addition to this, the OPAX method does not require mount stiffness data and allows a simultaneous identification of structural and acoustic paths.
Technical Paper

A One-Wire Brushless Integral Charging System for Earthmovers

1965-02-01
650288
It is apparent that a new generator and regulator design is needed to supply the additional electrical loads and meet the requirements for durability, reliability, and environmental protection on earthmoving equipment. The author discusses the d-c and alternator type systems which have been used to supply electrical needs. A detailed analysis of the integral charging system is presented. This system overcomes many of the shortcomings of the present electrical systems and, because it has a minimum number of moving parts, it is potentially the most reliable charging system in use on heavy duty equipment.
Standard

A Process Standard for the Storage, Retrieval and Use of Three-Dimensional Type Design Data

2003-09-04
HISTORICAL
ARP9034
This document describes requirements for standardized processes (and associated technologies) that ensure type design data are retrievable and usable for the life of a type certificate (50+ years). These processes are primarily concerned with, but not limited to, digital type design data retained in three-dimensional representations and associated data that is required for complete product definition, such as tolerances, specification call-outs, product structure and configuration control data, etc. This process standard includes process requirements for managing the evolution of technologies required to ensure the availability of the data for the life of the product. This data must be available to meet regulatory, legal, contractual and business requirements. This process standard is not intended to incorporate every company specific requirement and does not dictate specific organizational structures within a company.
Standard

A Process Standard for the Storage, Retrieval and Use of Three-Dimensional Type Design Data

2015-04-21
CURRENT
ARP9034A
This document describes requirements for standardized processes (and associated technologies) that ensure type design data are retrievable and usable for the life of a type certificate (50+ years). These processes are primarily concerned with, but not limited to, digital type design data retained in three-dimensional representations and associated data that is required for complete product definition, such as tolerances, specification call-outs, product structure and configuration control data, etc. This process standard includes process requirements for managing the evolution of technologies required to ensure the availability of the data for the life of the product. This data must be available to meet regulatory, legal, contractual and business requirements. This process standard is not intended to incorporate every company specific requirement and does not dictate specific organizational structures within a company.
Journal Article

A Sensitivity Analysis Formulation for Steady-State Conjugate Heat Transfer Problems of Industrial Size

2012-04-16
2012-01-0911
In recent years, developments in virtual prototyping have gained significant interest. The promise of cost savings and the need for rapid simulations in order to be able to offer various platforms has led to automated coupling of software for various physical models. But relying heavily on simulation necessitates confidence in the results obtained. By incorporating various physical models the number of parameters to be set increases. The uncertainties associated with these input parameters are propagated to the simulation results. Uncertainty analysis aims at quantifying those influences. In this paper local first order sensitivity analysis for conjugate heat transfer problems including cavity radiation is introduced. The issue of memory requirement associated with this approach for industrial sized cases is discussed.
Technical Paper

A Shift Timer for Automatic Transmissions

1970-02-01
700870
The time required for the shifting elements in an automatic transmission to complete their engagements is an important indicator of the performance of both friction elements and automatic transmission fluids. The common method of measuring shifting time via analog (chart) recording techniques is somewhat time consuming; moreover, it is subject to interpretative error and does not lend itself to quick, accurate determinations. A shift timing device that has been designed and built utilizing digital techniques gives an automatic unattended digital readout of shift time. The details of this timer and applications of it to automatic transmission fluid testing are discussed. THE TIME REQUIRED for the shifting elements in automatic transmissions to complete their engagements is an important indicator of transmission fluid and friction element performance and durability.
Technical Paper

A Statistical Analysis of Vehicle Rollover Propensity and Vehicle Stability

1992-02-01
920584
This report documents the accident data collection, processing and analysis methodology used by the National Highway Traffic Safety Administration (NHTSA) in a major agency agency investigation of the rollover propensity of light duty vehicles. Specifically, these efforts were initiated in response to two petitions for rulemaking requesting the development of a standard for rollover stability. Logistic regression models were used to investigate the ability of a number of stability measures to predict vehicle rollover propensity, while accounting for a number of driver and environmental factors. It is not the intent of this paper to document formal agency policy in the area of any possible rulemaking efforts, and as such, references to these activities are not discussed. The reader can obtain information on this activity through normal agency procedures.
Technical Paper

A Study of a Variable Compression Ratio System with a Multi-Link Mechanism

2003-03-03
2003-01-0921
This paper presents a variable compression ratio (VCR) system that has a new piston-crankshaft mechanism with multiple links. This multi-link mechanism varies the piston position at top dead center (TDC), making it possible to change the compression ratio of the engine continuously. Previous attempts have been made to achieve variable compression ratio with this type of method, but it was difficult to avoid various undesirable effects such as an increase in the engine size, substantial weight increases, increased engine block vibration due to a worsening of piston acceleration characteristics and increased friction resulting from a larger number of sliding parts. At the stage of developing the basic design of the multi-link geometry, emphasis was placed on selection of a suitable link geometry and optimization of the detailed dimensions with the aim of essentially resolving these previous issues.
Technical Paper

A Substructuring Formulation for the Energy Finite Element Analysis

2007-05-15
2007-01-2325
In applications of the Energy Finite Element Analysis (EFEA) there is an increasing need for developing comprehensive models with a large number of elements which include both structural and interior fluid elements, while certain parts of the structure are considered to be exposed to an external fluid loading. In order to accommodate efficient computations when using simulation models with a large number of elements, joints, and domains, a substructuring computational capability has been developed. The new algorithm is based on dividing the EFEA model into substructures with internal and interface degrees of freedom. The system of equations for each substructure is assembled and solved separately and the information is condensed to the interface degrees of freedom. The condensed systems of equations from each substructure are assembled in a reduced global system of equations. Once the global system of equations has been solved the solution for each substructure is pursued.
Technical Paper

A Theft Deterrent Program for Off-Highway Equipment

1983-02-01
830815
To deter theft of off-highway equipment, manufacturers must look at more than just putting padlocks on units. Most security devices can be overcome in some manner, given enough time. It then becomes a matter of establishing identification of the unit and determining rightful ownership. This requires having an identification number that is unique for each unit which can be readily found. If the primary identification number has been removed, a cross-check of component identification is needed. In addition, the owner must have some form of proof of ownership that cannot be copied or counterfeited.
Standard

A Tilt Table Procedure for Measuring the Static Rollover Threshold for Heavy Trucks

2011-05-17
CURRENT
J2180_201105
The test procedure applies to roll coupled units such as straight trucks, tractor semitrailers, full trailers, B-trains, etc. The test is aimed at evaluating the level of lateral acceleration required to rollover a vehicle or a roll-coupled unit of a vehicle in a steady turning situation. Transient, vibratory, or dynamic rollover situations are not simulated by this test. Furthermore, the accuracy of the test decreases as the tilt angle increases, although this is a small effect at the levels of tilt angle used in testing heavy trucks. The test accuracy is accepted for vehicles that will rollover at lateral acceleration levels below 0.5 g corresponding to a tilt table angle of less than approximately 27 degrees. Even so, the results for heavy trucks with rollover thresholds greater than 0.5 g could be used for comparing their relative static roll stability.
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