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Viewing 1 to 30 of 21570
2017-10-08
Technical Paper
2017-01-2198
Zhihong Li, Guoxiu Li, Lan Wang, Hongmeng Li, Jie Wang, Haizhou Guo, Shuangyi He
The electromagnetic valve driving mechanism is the significant equipment, which plays a vital role in the unit pump injection system; therefore, the performance of the electromagnetic valve directly influences the function of the control system. Based on the operation conditions of the unit pump injection system, a steady electromagnetic valve model was modified to study the influence factors of electromagnetic force and the best combination to get the maximum electromagnetic force. The validation model was verified by experiment. The effects of some crucial parameters upon the electromagnetic force were investigated in the present paper, (including working airspace, magnetic pole’s cross-sectional area, coil position, coil turn, the armature thickness). The result shows that the electromagnetic force of the solenoid valve enhanced with the increasing driving current and reduced with the decreasing of working condition.
2017-09-28 ...
  • September 28-29, 2017 (8:30 a.m. - 4:30 p.m.) - Ft. Worth, Texas
Training / Education Classroom Seminars
The avionics hardware industry world-wide is now commonly required to follow DO-254 Design Assurance Guidance for Airborne Electronic Hardware for literally all phases of development: Safety, Requirements, Design, Logic Implementation, V&V, Quality Assurance, etc. The DO-254 standard is a companion to the software DO-178B standard; however, there are many differences between hardware and software which must be understood. This basic course introduces the intent of the DO-254 standard for commercial avionics hardware development.
2017-09-28 ...
  • September 28, 2017 (8:30 a.m. - 4:30 p.m.) - Ft. Worth, Texas
Training / Education Classroom Seminars
The challenges associated with using composites as a replacement for aluminum reside primarily in the complex manufacturing processes and technologies for fabricating composite parts. The high cost of composites material and its manufacturing complexity have been inhibitors to the wide transfer of this technology to the non-aerospace market. The search for solutions to high manufacturing costs and efficient manufacturing processes have resulted in intense research by government, aerospace industry companies, and space agencies worldwide.
2017-09-12
Event
2017-09-04
Technical Paper
2017-24-0031
Imre Gergely Nagy, Andrea Matrisciano, Harry Lehtiniemi, Fabian Mauss, Andreas Schmid
Large two-stroke marine diesel engines have special injector geometries, which differ substantially from the configurations used in most other Diesel engine applications. One of the major differences is that injector orifices are distributed in a highly non-symmetric fashion that affects the spray morphology. Earlier investigations demonstrated the dependency of the spray morphology on the location of the spray orifice, and therefore on the resulting flow conditions at the nozzle tip. Thus, spray structure is directly affected by the flow structure within the orifice [1]. Following recent LES resolved spray primary breakup studies [2], the present paper focuses on spray secondary breakup modelling of asymmetric spray structures in Euler-Lagrangian framework based on previous droplet distributions of primary breakup. Firstly, the derived droplet distributions are assigned via user coding to RANS 3D-CFD simulation of two nozzle bore geometries having 0.0 and 1.1 mm eccentricity.
2017-09-04
Technical Paper
2017-24-0073
Carlo Beatrice, Giacomo Belgiorno, Gabriele Di Blasio, Ezio Mancaruso, Luigi Sequino, Bianca Maria Vaglieco
Technologies for direct injection of fuel in compression ignition engines are in continuous development in order to get an increasingly high injection pressure. One of the most investigated component of this system is the injector; in particular, main attention is given to the nozzles characteristics as diameter, number, angle, internal shape. The reduction of nozzle hole diameter seems the simplest way to increase the fuel velocity and to promote the atomization process. On the other hand, the number of the holes must increase to keep the desired mass flow. On this basis, a new logic has been applied for the development of the next generation of injectors. The tendency to increase the nozzle number and to reduce the diameter has led to the replacement of the nozzle with a circular plate that moves vertically. The plate motion allows to obtain a cylindrical surface for the delivery of the fuel on 360° degrees; while the plate lift is calibrated to obtain the desired fuel mass flow.
2017-09-04
Technical Paper
2017-24-0101
Pedro Marti-Aldaravi, Kaushik Saha, Jaime Gimeno, Sibendu Som
Abstract Actual combustion strategies in internal combustion engines rely on fast and accurate injection systems to be successful. One of the injector designs that has shown good performance over the past years is the direct-acting piezoelectric. This system allows precise control of the injector needle position and hence the injected mass flow rate. Therefore, understanding how nozzle flow characteristics change as function of needle dynamics helps to choose the best lift law in terms of delivered fuel for a determined combustion strategy. Computational fluid dynamics is a useful tool for this task. In this work, nozzle flow of a prototype direct-acting piezoelectric has been simulated by using CONVERGE. Unsteady Reynolds-Averaged Navier-Stokes approach is used to take into account the turbulence. Results are compared with experiments in terms of mass flow rate. The nozzle geometry and needle lift profiles were obtained by means of X-rays in previous works.
2017-09-04
Technical Paper
2017-24-0108
Alessandro Montanaro, Marianna Migliaccio, Luigi Allocca, Carlo Beatrice, Valentina Fraioli, Roberto Ianniello
Abstract In the present paper, a new concept of open nozzle spray was investigated as possible application for compression ignition engines. The study concerns an experimental and numerical characterization of a spray generated through a prototype high-pressure hollow-cone nozzle (HCN). The experimental description of the injection process was carried out under evaporative and non-evaporative conditions injecting the fuel in a constant-volume combustion vessel controlled in pressure and temperature in order to measure the spatial and temporal fuel pattern at engine-like gas densities. OpenFOAM libraries in the lib-ICE version of the numerical code were employed for simulating the spray dynamics after a first validation phase based on the experimental data. Results show a typical spray structure of the outward-opening nozzle with the overall fluid-dynamic arrangement having a good fuel distribution along the hollow-cone geometry but showing a reduced spatial penetration.
2017-09-04
Technical Paper
2017-24-0111
Heechang Oh, JuHun Lee, Seungkook Han, Chansoo Park, Choongsik Bae, Jungho Lee, In Keun Seo, Sung Jae Kim
Abstract In this study, the effect of the nozzle tip geometry on the nozzle tip wetting and particulate emissions was investigated. Various designs for the injector nozzle hole were newly developed for this study, focusing on the step hole geometry to reduce the nozzle tip wetting. The laser induced fluorescence technique was applied to evaluate the fuel wetting on the nozzle tip. A vehicle test and an emissions measurement in a Chassi-Dynamo were performed to investigate the particulate emission characteristics for injector nozzle designs. In addition, the in-cylinder combustion light signal measurement by the optical fiber sensor was conducted to observe diffusion combustion behavior during the vehicle test. Results showed that the step hole surface area is strongly related to nozzle tip wetting and particulate emissions characteristics.
2017-09-04
Technical Paper
2017-24-0005
Guillaume Goumy, Pascal Chesse, Nicolas Perrot, Rémi Dubouil
Abstract Downsizing has nowadays become the more widespread solution to achieve the quest for reaching the fuel consumption incentive. This size reduction goes with turbocharging in order to keep the engine power constant. To reduce the development costs and to meet the ever tightening regulations, car manufacturers rely more and more on computer simulations. Thus developing accurate and predictable turbocharger models functioning on a wide range of engine life cases became a major requirement in industrial projects. In the current models, compressors and turbines are represented by look-up tables, experimentally measured on a turbocharger test bench, at steady point and high inlet turbine temperature. This method results in limited maps : on the one hand the compressor surge line and on the other hand the flow resistance curve behind the compressor. Mounted on an engine, the turbocharger encounters a wider scale of functioning points.
2017-09-04
Technical Paper
2017-24-0023
Karim Gharaibeh, Aaron W. Costall
Abstract Internal combustion engines are routinely developed using 1D engine simulation tools. A well-known limitation is the accuracy of the turbocharger compressor and turbine sub-models, which rely on hot gas bench-measured maps to characterize performance. Such discrete map data is inherently too sparse to be used directly in simulation, and so a preprocessing algorithm interpolates and extrapolates the data to generate a wider, more densely populated map. Methods used for compressor map interpolation vary. They may be mathematical or physical in nature, but there is no unified approach, except that they typically operate on input map data in SAE format. For decades it has been common practice for turbocharger suppliers to share performance data with engine OEMs in this form. This paper describes a compressor map interpolation technique based on the nondimensional compressor flow and loading coefficients, instead of SAE-format data.
2017-09-04
Technical Paper
2017-24-0020
Michele Becciani, Alessandro Bianchini, Matteo Checcucci, Lorenzo Ferrari, Michele De Luca, Luca Marmorini, Andrea Arnone, Giovanni Ferrara
Abstract The onset of aerodynamic instabilities in proximity of the left margin of the operating curve represents one of the main limitations for centrifugal compressors in turbocharging applications. An anticipated stall/surge onset is indeed particularly detrimental at those high boost pressures that are typical of engine downsizing applications using a turbocharger. Several stabilization techniques have been investigated so far to increase the rangeability of the compressor without excessively reducing the efficiency. One of the most exploited solutions is represented by the use of upstream axial variable inlet guide vanes (VIGV) to impart a pre-whirl angle to the inlet flow. In the pre-design phase of a new stage or when selecting, for example, an existing unit from an industrial catalogue, it is however not easy to get a prompt estimation of the attended modifications induced by the VIGV on the performance map of the compressor.
2017-08-22 ...
  • August 22-23, 2017 (8:30 a.m. - 4:30 p.m.) - Tysons, Virginia
  • December 12-13, 2017 (8:30 a.m. - 4:30 p.m.) - Puyallup, Washington
Training / Education Classroom Seminars
Individuals responsible for quality management system, implementation, and transition to the AS9100:2016 series of standards for Aviation, Space, and Defense will require an understanding of the requirements for the preparation and execution of the audit process as defined in these revised standards. Management and implementers of AS9100:2016 Rev. D within these organizations must also be aware of what these changes may mean for their company.
2017-07-26 ...
  • July 26-27, 2017 (8:30 a.m. - 4:30 p.m.) - Troy, Michigan
  • December 4-5, 2017 (8:30 a.m. - 4:30 p.m.) - Puyallup, Washington
Training / Education Classroom Seminars
The requirements for producing an FAA approved replacement part can be daunting. Understanding the steps required in the FAA Parts Manufacturer Approval (PMA) process can greatly streamline the approval life-cycle and reduce unnecessary costs and delays, thereby shortening the time and cost to market. This course is designed for those organizations and individuals interested in designing and manufacturing replacement parts for civil aviation aircraft. This two-day course covers the crucial subjects and steps of the FAA-PMA approval process.
2017-07-24
WIP Standard
ARP5483/2A
This method outlines the standard procedure for testing the hardness of bearing components. Bearings covered by this test method shall be any rolling element bearing used in airframe control.
CURRENT
2017-07-20
Standard
J995_201707
This SAE Standard covers the mechanical and material requirements for three grades of steel nuts suitable for use in automotive and related engineering applications, in sizes 1/4 to 1-1/2 inches, inclusive, and with dimensions conforming with the requirements of the latest issue of SAE J482 or ASME B18.2.2, except for machine screw nuts which are not covered in this standard. This document does not include limits for surface discontinuities. Where usage requires such control, limits may be specified separately. For sizes 1/4 through 1 inch, this may be done by the statement: “Surface discontinuities shall not exceed the limits specified in ASTM F812/F812M.”
2017-07-19
WIP Standard
J1939DA_201707
This document is intended to supplement the J1939 documents by offering the J1939 information in a form that can be sorted and search for easier use. The J1939 Digital Annex, introduced in August 2013, offers key J1939 technical data in an Electronic Spreadsheet that can be easily searched, sorted, and adapted to other formats. J1939DA contains all of the SPNs (parameters), PGNs (messages), and other J1939 data previously published in the SAE J1939 top level document. J1939DA also contains all of the SLOTs, Manufacturer ID Codes, NAME Functions, and Preferred Addresses previously published in the SAE J1939 top level and the J1939-71 document. J1939DA contains the complete technical details for all of the SPNs and PGNs previously published in the SAE J1939-71 document. It also includes the supporting descriptions and figures previously published in the SAE J1939-71 document.
Viewing 1 to 30 of 21570

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