Criteria

Display:

Results

Viewing 241 to 270 of 4781
2011-08-30
Technical Paper
2011-01-1981
Sanghoon Kook, Minh Khoi Le, Srinivas Padala, Evatt R. Hawkes
Schlieren and shadowgraph imaging have been used for many years to identify refractive index gradients in various applications. For evaporating fuel sprays, these techniques can differentiate the boundary between spray regions and background ambient gases. Valuable information such as the penetration rate, spreading angle, spray structure, and spray pattern can be obtained using schlieren diagnostics. In this study, we present details of a z-type schlieren system setup and its application to port-fuel-injection gasoline sprays. The schlieren high-speed movies were used to obtain time histories of the spray penetration and spreading angle. Later, these global parameters were compared to specifications provided by the injector manufacturer. Also, diagnostic parameters such as the proportion of light cut-off at the focal point and the orientation of knife-edge (schlieren-stop) used to achieve the cut-off were examined.
2011-08-30
Technical Paper
2011-01-1965
Reijo Makinen, Nils-Olof Nylund, Kimmo Erkkilä lng, Pirjo Saikkonen, Arno Amberla
Helsinki Region Transport, Neste Oil, Proventia Emission Control and VTT Technical Research Centre of Finland carried out a 3.5 year PPP venture “OPTIBIO” to demonstrate the use of paraffinic renewable diesel (hydrotreated vegetable oil HVO) in city buses. The fleet test in Metropolitan Helsinki involving some 300 buses is the largest one in the world to demonstrate this new fuel. The fuels were a 30 % blend of renewable diesel and 100 % renewable diesel. This paper describes the overall set-up of the project, gives an overview of the emission results as well as presents experience from the field.
2011-06-13
Technical Paper
2011-38-0035
Colin Hatch, Richard Moser, Roger Gent, Peter Hicks
The demand for low power ice protection systems and the introduction of further regulations for flight into known icing will stretch current technologies and the analytical tools required to support them. This paper considers an approach in the development of an analysis tool for the assessment of a combined electro-thermal and electro-mechanical deicing system. The tool development is part of a 4 year EU programme (project ‘HETEMS’ - Hybrid ElectroThermal and ElectoMechanical Simulation) and will include the icing wind tunnel testing of a hybrid deicing system to provide validation data. The various analytical components required by the system are presented and some of the issues in applying them are discussed. The tool will aim to provide both a 2D and 3D capability and allow both conceptual and detailed design strategies.
2011-06-13
Technical Paper
2011-38-0045
Guy Fortin, Ilham Enneji, Arlene Beisswenger, Jean Perron
Deicing and anti-icing fluids are used to remove and prevent ice formation on aircraft before takeoff. Holdover times (HOT) published by the FAA are used by pilots as guidelines indicating the amount of effective time of a fluid under certain freezing precipitation types. However, the times on these tables are based on endurance time tests involving a visual estimate of failure on a flat plate [1]: when 30% of the fluid is covered with white snow under snow precipitation, although the times have been correlated to aircraft wing tests [2] they do not address the mechanism of fluid failure. To measure and understand the fluid mechanisms conducting to failure, the Anti-icing Materials International Laboratory (AMIL) developed a simplified test with a generic deicing propylene glycol-based fluid. The test consisted of pouring 400 mL of the generic deicing fluid on a 5 dm by 3 dm level flat plate where the plate edges were rimmed with insolated walls to make a waterproof open box.
2011-06-13
Technical Paper
2011-38-0058
Arlene Beisswenger, Caroline Laforte, Jean Perron
Deicing fluids are used to remove and prevent ice formation on aircraft before takeoff. These fluids are essentially composed of water, a freeze point depressant (FPD) usually glycol, a surfactant or wetting agent and a corrosion inhibitor. All commercial fluids are qualified to SAE (Society of Automotive Engineers) specifications, which test for aerodynamic acceptance, anti-icing endurance, corrosion inhibition, material compatibility, fluid stability and environment. However, these tests have been built around a fluid with a glycol FPD. More recently, with environmental pressure, fluids with other FPDs have been developed and qualified. The other FPDs include: acetates and formate salts, sorbitol, and other undisclosed FPDs. The acetates and formates, which came out in the early 1990s led to suspected corrosion problems. This led to the additional requirement for corrosion tests for non-glycol deicing fluids in paragraph 3.1.1 of AMS1424.
2011-06-13
Technical Paper
2011-38-0098
Austin Overmeyer, Jose Luis Palacios, Edward C. Smith, Roger Royer
Ultrasonic excitation has proven to provide ice interface transverse shear stresses exceeding the adhesion strength of freezer and wind tunnel ice to various metals, promoting instantaneous ice delamination. Prior proof-of-concept testing presented issues related to piezoelectric actuator cracking under ultrasonic tensile excitation, as well as actuator debonding from the host structure. The aim of this research is to provide solutions to the actuator reliability issues encountered during prior research and to perform rotor icing testing to validate the proposed solutions. Three different approaches are taken to solve the issues related with actuator failure during de-icing processes: custom-designed controllers to ensure the excitation of desired ultrasonic resonance modes, compression only driving of the actuator, and optimization of actuator thickness.
2011-06-13
Technical Paper
2011-38-0096
Shinan Chang
Electro-thermal deicing process was an unsteady heat transfer process including phase change. Based on the investigation of such a process, a code was developed to numerically simulate electro-thermal deicing process. Phase change was performed by an enthalpy method. A staircase approach was used to describe the variable ice thicknesses along the icing surface. The control volume method was adopted to discretize the governing equations. Tri-diagonal matrix method, alternating direction implicit method and block-correction technique were used to solve the discrete equations. Results of temperature distribution in this investigation were compared with experimental results of previous study. Their good agreements indicate the validity of our simulation. The effects of icing conditions, such as ambient temperature, liquid water content (LWC) and flight velocity, etc., were analyzed through a case. Some useful conclusions were achieved.
2011-06-13
Technical Paper
2011-38-0104
Mariusz Kubryn, Robert Flemming, Ben Bernstein, Janusz Pietruszka
PZL Mielec is in the process of certificating the ice protection systems installed on the M28 turboprop aircraft so that customers of that aircraft may operate in icing conditions. The M28 airplane is derived from the Antonov An-28, which was certificated in Russia to their icing certification requirements many decades ago. The M28 is equipped with a lot of western equipment, including Pratt and Whitney Canada engines and Hartzell propellers, and now has a no-hazard certification for the use of the installed ice protection system. The M28 ice protection equipment includes wing and tail anti-icing, engine inlet anti-icing, propeller deicing, and wing strut deicing. These systems have undergone a series of development flight tests and icing wind tunnel tests. This paper presents an overview of the flight tests and wind tunnel tests conducted to date.
2011-06-13
Technical Paper
2011-38-0010
Katsuaki Morita, Koji Okamoto, Akihito Aoki, Shigeo Kimura, Hirotaka Sakaue
Anti- or de-icing of an aircraft is necessary for a safe flight operation. Mechanical processes, such as heating and deicer boot, are widely used. Deicing fluids, such as ethylene glycol, are used to coat the aircraft. However, these should be coated every time before the take-off, since the fluids come off from the aircraft while cruising. We study a hydrophobic coating as an anti-icer for an aircraft. It is designed to coat on the aircraft without removal. Since a hydrophobic coating prevents water by reducing the surface energy, it would be an alternative to prevent ice on the aircraft. We provide a temperature-controlled room, which can control its temperature under icing conditions (-10 to 0 °C). The contact angle and the sliding angle are tested for various hydrophobic coatings. Candidate coatings are tested under super-cooled water spraying and under the representative in-flight icing conditions.
2011-06-13
Technical Paper
2011-38-0097
Roger J. Aubert, Jason Wright
As the technology in rotor deicing matures, more programs are willing to engage in the certification of their helicopters for flight into icing conditions. The S-92A™ helicopter, AW139, V-22, and EC225 aircraft have been certified/qualified recently and are illustrative examples of such engagement. The state-of-the-art configuration definition of rotor ice protection systems that have been introduced into the western rotorcraft manufacturer's production line has been limited to electro-thermal deicing systems. System configurations may use either chordwise or spanwise shedding schemes and could differ in design and operation. Regardless of the selected design configuration, an analysis of the required extent of protection coverage must be performed unless one has access to data offering sufficient similitude in terms of airfoil geometry and flight conditions.
2011-06-13
Technical Paper
2011-38-0085
Satya P. Chauhan, Melissa Roshon, W. D. Samuels, H. Nick Conkle, Elizabeth Berman, Mary Wyderski
Currently the U. S. Department of Defense (DoD) exclusively uses potassium acetate (KAc)-based runway deicing fluids (RDFs) to deice and anti-ice military runways and taxiways. Commercial airports predominantly use KAc, but some also use RDFs composed of KAc plus propylene glycol (PG) or urea plus PG. Conventional RDFs have environmental concerns due to toxicity as well as material compatibility problems such as corrosion of aircraft carbon brake-pad components, cadmium-plated landing gear, and airfield lighting fixtures. Under the Strategic Environmental Research and Development Program (SERDP), Battelle tested a series of patented - bio-based RDFs to address these issues. Tests showed that the Battelle RDFs met the mandatory Aerospace Material Specification (AMS) 1435 requirements. These new RDFs have reduced ecotoxicity compared to currently used RDFs and are compliant with all other environmental requirements.
2011-06-13
Technical Paper
2011-38-0029
George A. Isaac, Monika Bailey, Faisal Boudala, Stewart G. Cober, Robert Crawford, Norman Donaldson, Ismail Gultepe, Bjarne Hansen, Ivan Heckman, Laura Huang, Alister Ling, Janti Reid, Marc Fournier
The Canadian Airport Nowcasting Project (CAN-Now) has developed an advanced prototype all-season weather forecasting and nowcasting system that can be used at major airports. This system uses numerical model data, pilot reports, ground in-situ sensor observations (precipitation, icing, ceiling, visibility, winds, etc), on-site remote sensing (such as vertically pointing radar and microwave radiometer) and off-site remote sensing (satellite and radar) information to provide detailed nowcasts out to approximately 6 hours. The nowcasts, or short term weather forecasts, should allow decision makers at airports such as pilots, dispatchers, de-icing crews, ground personnel or air traffic controllers to make plans with increased margins of safety and improved efficiency. The system is being developed and tested at Toronto Pearson International Airport (CYYZ) and Vancouver International Airport (CYVR).
2011-06-13
Technical Paper
2011-38-0102
Thomas Reid, Guido S. Baruzzi, Isik A. Ozcer, Wagdi G. Habashi
The assessment of an unsteady approach for the simulation of in-flight electro-thermal de-icing using a Conjugate Heat Transfer (CHT) technique is presented for a NACA0012 wing and a swept wing. This approach is implemented in the FENSAP-ICE in-flight icing system, and provides simulation capabilities for the heat transfer and ice accretion phenomena occurring during in-flight de-icing with power cycling through several heater pads. At each time step, a thermodynamic balance is established between the water film, the ice layer and the solid domains. The ice shape is then modified according to ice accretion and melting rates. Numerical results show the complex interactions between the water film, the ice layer and the heating system. The NACA0012 validation test case compares well against one of the very few experimental de-icing test cases available in the open literature.
2011-06-13
Technical Paper
2011-38-0078
Michael Papadakis, Paul Strong, See-Cheuk Wong
An experimental methodology for investigating the effects of anti-icing fluids is presented in this paper. A wing model was designed, fabricated, and instrumented for testing anti-icing fluids in a wind tunnel facility. In addition, a video capturing method was developed and used to document fluid behavior during simulated takeoff tests. The experiments were performed at the Wichita State University 2.13-m by 3.05-m (7-ft by 10-ft) wind tunnel facility with two pseudoplastic fluids representative of Type IV anti-icing fluids. The experimental data obtained included fluid wave propagation speeds, chordwise fluid thickness distributions as a function of time, and boundary layer velocity profiles for the clean and fluid contaminated wing model at select chordwise stations. During simulated takeoffs with initial fluid depths of either 4 mm or 2 mm, the fluids were observed to thin in the forward (upstream) regions of the wing model and accumulate in the aft regions.
2011-06-13
Technical Paper
2011-38-0084
Devon Seal, John Lengel, Timothy Arendt
Airports and airlines continue to work together to offer safe, reliable and cost-effective access to the world. There are many complex interactions at an airport, and addressing environmental issues is just one of the many functions an airport and airline must master. One of the key environmental issues affecting airports/airlines where frost or freezing conditions occur is the safe, efficient and environmentally protective management of deicer-affected storm water. Even those airports in the warmer southern United States have periods of freezing weather, whereby aircraft must be deiced. Although infrequent, the potential exists for adverse effects, and the need to establish a management plan based on risk is paramount.
2011-04-12
Technical Paper
2011-01-0008
Sunghyun Kim, Hyungil Kim, Dongseok Kim, Youngjn Cho
The insurance rating has been differentiated in grades according to cost of repair for damaged vehicles and has been an important consideration point for customers when buying a new vehicle. The RCAR (Research Council for Automobile Repairs) has evaluated low speed damageability and reparability of cars. Vehicle manufacturers have tried to reduce the repair cost by designing vehicles with the intent to minimize damage sustained in low speed crash. Repair costs can be reduced by isolating damage through energy absorption structures or damaged structures and components repair or replace easily, quickly and cost effectively. This paper demonstrates an idea to achieve a reduction in repair cost and improve damageability and reparability of the structure and components.
2011-04-12
Technical Paper
2011-01-0749
Kallappa Pattada, Satnam Singh, Pulak Bandyopadhyay
This paper presents an interactive, fault model-based prototype diagnostic tool that will assist service technicians in isolating the root cause of vehicle problems and performing corrective repairs. Current automotive service procedures are driven primarily by static service manuals that inform technicians on the service steps in case a specific diagnostic trouble code (DTC) is set in a vehicle. Although comprehensive, these service procedures usually require technicians to gather and integrate diagnostic information from several sources, such as DTCs, customer complaints and manual test results. This can lead to increased repair time and labor costs. The fault model-based interactive service procedure tool discussed in this paper will guide the technician to isolate the fault and provide him/her with recommendations for the correct repair actions. The tool uses a fault model, built using service procedures information, historical repair data and engineering inputs.
2011-04-12
Journal Article
2011-01-0965
Mandar Hazare, Paul J Th Venhovens
The U.S. NHTSA has established the FMVSS 126 standard that requires all vehicles sold in the U.S. to include an ESC system as standard equipment after September 1 st , 2011. There is growing concern among aftermarket suppliers specialized in development and installation of vehicle performance parts that chassis modifications may cause the ESC systems to be inoperative or can create unforeseen issues with stability and safety systems. This industry is in need of a process to support the development and validation of chassis modification. The authors propose the implementation of SIL and HIL simulations as a solution to the problem statement. Based on the results of a sensitivity analysis, guidelines for safe aftermarket modifications will be presented.
2011-04-12
Technical Paper
2011-01-0521
Landon Onyebueke, Akindeji Ojetola, Edward Winkler
This paper presents a PC based mathematical and rapid prototyping technique for anthropometric accommodation in a maintenance environment using the principle of simulation based design. The developed technique is capable of analyzing anthropometric data using multivariate (Principal component Analysis) approach to describe the body size variability of any given population. A number of body size representative cases are established which, when used properly within the constraints of the maintenance environments, will ensure the accommodation of a desired percentage of a population. This technique evaluates the percentage accommodation of a given population for the environment using the specific manikin cases as boundary conditions. In the case where any member of a maintenance crew cannot be accommodated, the technique has the capability of informing the designer of the environment why the member(s) is/are not accommodated.
2011-04-12
Technical Paper
2011-01-0750
John Cardillo
Most people still remember the introduction of the IBM PC in 1981 and the first Microsoft Windows operating system in 1985. These were the pioneering technologies that started a revolution in automotive test equipment in the service bay. What was once a purely mechanical garage environment where information was published annually in large paper manuals has evolved into a highly technical computing environment. Today vehicle networks link onboard vehicle control systems with diagnostic systems and updated service information is published daily over the Internet. A lot has changed over the last twenty years, and manufacturers of diagnostic test equipment are learning to deal with the constantly evolving computing platforms and host operating systems. This paper traces the history of automotive diagnostic equipment at Ford Motor Company and shares some of the hard lessons learned from the early systems.
2011-04-12
Technical Paper
2011-01-0747
Sergey Kirillov, Aleksander Kirillov Sr, Olga Kirillova
This paper introduces architecture of an integrated system of preventive diagnostics and mathematical and computational methods, based on which such a system is being developed. The present work aims to: describe the methods of preventive diagnostics based on mathematical models and computing algorithms, allowing to detect the hidden harbingers of engine dysfunctions and future failures; describe the architecture of the system of preventive diagnostics, its further evolution; describe the process of integration of preventive diagnostics system to the car engine. A necessary condition for the development system of preventive diagnosis is the condition of their economic efficiency, including the requirement of low cost sensors and computing systems of diagnostics.
2011-04-12
Journal Article
2011-01-0725
Zissimos Mourelatos, Jing Li, Vijitashwa Pandey, Amandeep Singh, Matthew Castanier, David A. Lamb
Understanding reliability is critical in design, maintenance and durability analysis of engineering systems. A reliability simulation methodology is presented in this paper for vehicle fleets using limited data. The method can be used to estimate the reliability of non-repairable as well as repairable systems. It can optimally allocate, based on a target system reliability, individual component reliabilities using a multi-objective optimization algorithm. The algorithm establishes a Pareto front that can be used for optimal tradeoff between reliability and the associated cost. The method uses Monte Carlo simulation to estimate the system failure rate and reliability as a function of time. The probability density functions (PDF) of the time between failures for all components of the system are estimated using either limited data or a user-supplied MTBF (mean time between failures) and its coefficient of variation.
2011-04-12
Journal Article
2011-01-0726
Dan Ghiocel, Dan Negrut, David A. Lamb, David Gorsich
This research paper addresses the ground vehicle reliability prediction process based on a new integrated reliability prediction framework. The integrated stochastic framework combines the computational physics-based predictions with experimental testing information for assessing vehicle reliability. The integrated reliability prediction approach incorporates the following computational steps: i) simulation of stochastic operational environment, ii) vehicle multi-body dynamics analysis, iii) stress prediction in subsystems and components, iv) stochastic progressive damage analysis, and v) component life prediction, including the effects of maintenance and, finally, iv) reliability prediction at component and system level. To solve efficiently and accurately the challenges coming from large-size computational mechanics models and high-dimensional stochastic spaces, a HPC simulation-based approach to the reliability problem was implemented.
2011-04-12
Journal Article
2011-01-0728
Amandeep Singh, Zissimos Mourelatos, Efstratios Nikolaidis
Reliability is an important engineering requirement for consistently delivering acceptable product performance through time. As time progresses, the product may fail due to time-dependent operating conditions and material properties, component degradation, etc. The reliability degradation with time may increase the lifecycle cost due to potential warranty costs, repairs and loss of market share. Reliability is the probability that the system will perform its intended function successfully for a specified time interval. In this work, we consider the first-passage reliability which accounts for the first time failure of non-repairable systems. Methods are available in the literature, which provide an upper bound to the true reliability which may overestimate the true value considerably. Monte-Carlo simulations are accurate but computationally expensive.
2010-10-25
Technical Paper
2010-01-2246
Kevin R. Sholes, Kiyotaka Shouji, Tomohiro Chaya, Jay B. Jeffries, Jason M. Porter, Sung Hyun Pyun, Ronald K. Hanson
Simultaneous crank-angle-resolved measurements of gasoline vapor concentration, gas temperature, and liquid fuel droplet scattering were made with three-color infrared absorption in a direct-injection spark-ignition engine with premium gasoline. The infrared light was coupled into and out of the cylinder using fiber optics incorporated into a modified spark plug, allowing measurement at a location adjacent to the spark plug electrode. Two mid-infrared (mid-IR) laser wavelengths were simultaneously produced by difference-frequency-generation in periodically poled lithium niobate (PPLN) using one signal and two pump lasers operating in the near-infrared (near-IR). A portion of the near-IR signal laser residual provided a simultaneous third, non-resonant, wavelength for liquid droplet detection. This non-resonant signal was used to subtract the influence of droplet scattering from the resonant mid-IR signals to obtain vapor absorption signals in the presence of droplet extinction.
2010-10-25
Journal Article
2010-01-2253
Rik Baert, Arno Klaassen, Erik Doosje
Existing gasoline DI injection equipment has been modified to generate single hole pulsed gas jets. Injection experiments have been performed at combinations of 3 different pressure ratios (2 of which supercritical) respectively 3 different hole geometries (i.e. length to diameter ratios). Injection was into a pressure chamber with optical access. Injection pressures and injector hole geometry were selected to be representative of current and near-future DI natural gas engines. Each injector hole design has been characterized by measuring its discharge coefficient for different Re-levels. Transient jets produced by these injectors have been visualized using planar laser sheet Mie scattering (PLMS). For this the injected gas was seeded with small oil droplets. The corresponding flow field was measured using particle image velocimetry (PIV) laser diagnostics.
2010-10-25
Journal Article
2010-01-2251
Jay B. Jeffries, Jason M. Porter, Sung Hung Pyun, Ronald K. Hanson, Kevin R. Sholes, Kiyotaka Shouji, Tomohiro Chaya
Simultaneous crank-angle-resolved measurements of gasoline concentration and gas temperature were made with two-color mid-infrared (mid-IR) laser absorption in a production spark-ignition engine (Nissan MR20DE, 2.0L, 4 cyl, MPI with premium gasoline). The mid-IR light was coupled into and out of the cylinder using fiber optics incorporated into a modified spark plug. The absorption line-of-sight was a 5.3 mm optical path located closely adjacent to the ignition spark providing spatially resolved absorption. Two sensor wavelengths were selected in the strong bands associated with the carbon-hydrogen (C-H) stretching vibration near 3.4 μm, which have an absorption ratio that is strongly temperature dependent. Fuel concentration and temperature were determined simultaneously from the absorption at these two wavelengths.
2010-10-25
Journal Article
2010-01-2254
Russell P. Fitzgerald, Richard R. Steeper
An infrared laser absorption technique has been developed to measure in-cylinder concentrations of CO in an optical, automotive HCCI engine. The diagnostic employs a distributed-feedback, tunable diode laser selected to emit light at the R15 line of the first overtone of CO near 2.3 μm. The collimated laser beam makes multiple passes through the cylinder to increase its path length and its sampling volume. High-frequency modulation of the laser output (wavelength modulation spectroscopy) further enhances the signal-to-noise ratio and detection limits of CO. The diagnostic has been tested in the motored and fired engine, exhibiting better than 200-ppm sensitivity for 50-cycle ensemble-average values of CO concentration with 1-ms time resolution. Fired results demonstrate the ability of the diagnostic to quantify CO production during negative valve overlap (NVO) for a range of fueling conditions.
2010-10-25
Technical Paper
2010-01-2262
Cinzia Tornatore, Simona Merola, Paolo Sementa
Nowadays an elevated number of two, three and four wheels vehicles circulating in the world-wide urban areas is equipped with Port Fuel Injection Spark Ignition (PFI SI) engines. Their technological level is high, but a further optimization is still possible, especially at low engine speed and high load. To this purpose, the scientific community is now focused on deepening the understanding of thermo fluid dynamic phenomena that takes place in this kind of engine: the final purpose is to find key points for the reduction in engine specific fuel consumption and exhaust emissions without a decrease in performance. In this work, the combustion process was investigated in an optically accessible single cylinder PFI SI engine. It was equipped with the head, injection device and exhaust line of a commercial small engine for two-wheel vehicles, it had the same geometrical characteristics in terms of bore, stroke and compression ratio.
2010-10-19
Technical Paper
2010-01-2314
Niall T. Berkery
Abstract Connectivity, software and services are the key elements that will define the next-generation vehicle experience. Drivers are being provided new innovative solutions that seamlessly integrate their online digital lifestyle into their vehicle environment, enabling automakers increased opportunity for brand differentiation, while giving drivers the ability to personalize their vehicles down to an individual level. This will be accomplished through “virtual accessorization” - where drivers will personalize their connected vehicle experience by choosing applications and services that best suit their individual needs. After selecting applications from an online automotive apps exchange, the apps are sent wirelessly to the car or the driver's smartphone for immediate use. The in-vehicle apps can also be configured based on who is driving, so that preferences and personal functionality moves with each driver.
Viewing 241 to 270 of 4781