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2017-09-04
Technical Paper
2017-24-0023
Karim Gharaibeh, Aaron W. Costall
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 generally rely on hot gas bench-measured maps to characterize their performance. Such discrete map data is inherently too sparse to be used directly in simulation, and so a pre-processing algorithm interpolates and extrapolates the data to generate a wider and 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 for the fact that they often operate on input map data in SAE standard format. Indeed, for decades it has been common practice for turbocharger suppliers to share performance data with their engine OEM customers in this form.
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
2017-24-0005
Guillaume Goumy, Pascal Chesse, Nicolas Perrot, Rémi Dubouil
Turbocharging has nowadays become a common solution to complete downsizing in the quest for reaching the new polluting emission constraints. Besides to reduce the developing costs and meet the ever tightening regulations, car manufacturer relies more and more on computer simulations. Thus developing an accurate and predictable turbocharger model, functioning on a wide range of engine life cases, is now a requirement. 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 : the compressor choke line depends on the test bench, and a typical turbine iso-speed is limited to a 0.5 ratio range. Put up on an engine, the turbocharger encounters a wider scale of functioning points. using only the present compressor and turbine maps in an engine simulation model no enough.
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
The onset of aerodynamic instabilities towards the left margin of the operating curve represents one of the main limitations for centrifugal compressors for turbocharging applications. Anticipated stall/surge onset is particularly critical at those high boost pressures that are typical of downsizing applications using a turbocharger. Several stabilization techniques have been investigated so far to increase the rangeability of the compressor, without too relevant detriment of its efficiency. One of the most exploited solutions in this sense is represented by the use of upstream axial variable inlet guide vanes (VIGV). 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 have a prompt estimation of the attended modifications induced by the VIGV on the performance map of the compressor.
2017-09-04
Technical Paper
2017-24-0108
Alessandro Montanaro, Marianna Migliaccio, Luigi Allocca, Carlo Beatrice, Valentina Fraioli, Roberto Ianniello
The combustion efficiency in modern diesel engines strictly depends on the quality of the air-fuel mixing and, in turn, the quality of spray atomization process. The air-fuel mixing is strongly influenced by the injection pressure, the geometry of the nozzle and the hydraulic characteristics of the injector. In this context, outward-opening piezoelectric injectors are gaining popularity as a high efficient device because of its precise control of the fuel injected. In the present paper, a new concept of open nozzle spray was investigated being a possible application for diesel engines. The study concerns an experimental and numerical characterization of a spray generated through a prototype high-pressure hollow-cone nozzle (HCN).
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
In this study, the effect of nozzle tip geometry on nozzle tip wetting and particulate emissions was investigated. Various design concepts of injector nozzle hole were newly developed for this study. Spray and emission characteristics of each concept were discussed with experimental results. The macroscopic spray visualization was carried out in a constant volume chamber to investigate general spray characteristics of each nozzle hole concept. The laser induced fluorescence technique was applied to evaluate fuel wetting characteristics on the nozzle tip. The vehicle test and emissions measurement in chassi dynamo were performed to investigate particulate emission characteristics for various injector nozzle designs. In addition, during a vehicle test, the in-cylinder combustion visualization with the optical fiber sensor (AVL VISIO VOLUME) was conducted to provide a comprehensive understanding of diffusion combustion and wetting behavior.
2017-09-04
Technical Paper
2017-24-0101
Pedro Marti-Aldaravi, Kaushik Saha, Jaime Gimeno, Sibendu Som
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 so 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 v2.3.10. Unsteady Reynolds-Averaged Navier-Stokes approach is used to take into account the turbulence. Simulations are able to properly capture the relationship between instantaneous partial needle lifts and the corresponding rate of injection.
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.
2017-08-29
Journal Article
2017-01-9001
Hermann Ferschitz, Michael Wannemacher, Otto Bucek, Florian Knöbel, Wolfgang Breitfuß
Abstract RTA Rail Tec Arsenal Fahrzeugversuchsanlage GmbH has focused on the simulation of in-flight icing conditions since 2012. Following the successful implementation of the icing conditions specified in EASA CS-25 Appendix C, it was expected that the facility could also be used to simulate the SLD conditions required by EASA CS-25 Appendix O. This paper sets forth theoretical considerations concerning the selection of suitable nozzles and their operation in the existing facility. The transport of large droplets through the contraction nozzle was simulated using a CFD program. The results then served as a basis for deriving secondary droplet breakup. The validations carried out confirm the theoretical considerations and identify potential limits and open research questions.
2017-07-10
Technical Paper
2017-28-1934
Anil Thakur, Md Tauseef Alam, Venkatesh Kumar PS, P D Kulkarni, Senthur Pandian
Abstract Current high rating thermal loaded engines must have super-efficient lubrication system to provide clean oil at appropriate pressure and appropriate lube oil temperature to every part of the engine at all engine RPM speeds and loads. So oil pump not only have to satisfy above parameters but also it should be durable till engine life. Gerotor pumps are internal rotary positive-displacement pumps in which the outer rotor has one tooth more than the inner rotor. The gear profiles have a cycloidal shape. Both are meshed in conjugate to each other. Gerotor takes up engine power through crankshaft and deliver to various engine consumers at required pressure and required time. Over the complete engine rpm speed and loads range, oil pump need to perform efficiently to provide proper functioning of the engine.
2017-07-10
Technical Paper
2017-28-1928
Rajesh Babu Channamaneni, P Kannan, Prasad Padavala
Abstract Engine mounts and mounting brackets play a critical role in determining NVH performance of a vehicle. A lot of work has been done in the area of virtual simulation using FE models to study engine mounting system performance and its impact on vehicle level performance. An overall approach towards engine mounting system validation at vehicle level is also very critical to validate simulation results in a prototype based on which further refinement work will be carried. In this paper a detailed procedure for engine mount and mounting bracket physical validation at vehicle level is presented. Various tests to be performed at vehicle level to quantify engine mount and mounting bracket performance parameters is discussed in detail along with measurement procedures and techniques. Test results are interpreted and its impact on overall performance is also explained.
2017-07-10
Technical Paper
2017-28-1947
Suresh Kumar Kandreegula, Kamal Rohilla, Naveen Sukumar, Kunal Kamal
Abstract A propeller shaft is a mechanical component of drive train that connects transmission to drive wheels/axle with the goal to transfer rotation and torque. It is used when the direct connection between transmission and drive axle is not possible due to large distance between their respective assigned design spaces. In commercial vehicles especially in heavy duty (GVW/GCW>15 tons) a single piece propeller shaft is seldom used due to its inherent disadvantages and therefore, most if not all, of the setups consists of multiple pieces of propeller shaft which are directly mounted on to frame cross members with the help of mounting brackets. As such the mounting bracket assembly undergoes various dynamic and static loading conditions and should be able to withstand these loads. This paper will focus on the FEA analysis of propeller shaft mounting assembly system.
2017-07-10
Technical Paper
2017-28-1948
John Samuel Kopppula, Thundil Karuppa Raj Rajagopal, Edison Gundabattini
Abstract The present work is concentrated to study the effect of varying inlet pressures on the dynamics of the suction valve obtained from a hermetic reciprocating compressor. The effect of valve functioning on the efficiency of a compressor is highly acceptable. Rather than the delivery valve, the suction valve has a significant impact on the compressor efficiency. The reed valve in a hermetic compressor is a cantilever type arrangement. The valve operates due to the pressure difference between the suction muffler and the cylinder. The numerical analysis which includes Fluid-structure interaction is used in the present study. The flow and structural domain employed in the present study are modelled with Solidworks 15.0. The fluid structure interaction analysis is a combination of ANSYS Fluent and ANSYS structural. These two are coupled with a system coupling in ANSYS Workbench 16.0. The numerical results obtained from the simulation are validated with the experimental data.
2017-07-10
Technical Paper
2017-28-1961
Shishir Sirohi, Saurabh Yadav, B. Ashok, V Ramesh Babu, C Kavitha, K Nantha Gopal
The main objective of the study is to design and analyze casing and supports of a transmission system for an electric vehicle. The system comprises of motors as the power source, constant mesh gear box coupled with limited slip differential as the power transmitting source. The space occupied by the transmission system is a foremost constraint in designing the system. The wear and tear in the system are caused by the gear meshing process and transmission error which lead to failure of the transmission system. This internal excitation also produces a dynamic mesh force, which is transmitted to the casing and mounts through shafts and bearings. In order to overcome such issues in a transmission system, a gear box casing, differential mounts and motor mounts have been designed by the use of CAD-modelling software “SOLIDWORKS”. The designs were imported to FEA software “ANSYS” for carrying out static structural analysis.
CURRENT
2017-06-26
Standard
AS1010H
(A) Propose Revision To Figure 1 To Show Port #1 Is Per AS4377 Style "S" In Both Cases and General Update (B) Propose revision to add conductive high purity aluminum coating per MIL-DTL-83488 for aluminum alloy fittings. The W code aluminum parts with new finish will be distinguished by new finish code V at the end of part number.
CURRENT
2017-06-26
Standard
AS4663C
Propose revision to add conductive high purity aluminum coating per MIL-DTL-83488 for aluminum alloy fittings. The W code aluminum parts with new finish will be distinguished by new finish code V at the end of part number.
CURRENT
2017-06-26
Standard
AS4666C
Propose revision to add conductive high purity aluminum coating per MIL-DTL-83488 for aluminum alloy fittings. The W code aluminum parts with new finish will be distinguished by new finish code V at the end of part number.
CURRENT
2017-06-26
Standard
AS4667B
Propose revision to add conductive high purity aluminum coating per MIL-DTL-83488 for aluminum alloy fittings. The W code aluminum parts with new finish will be distinguished by new finish code V at the end of part number.
CURRENT
2017-06-26
Standard
AS4678D
Propose revision to add conductive high purity aluminum coating per MIL-DTL-83488 for aluminum alloy fittings. The W code aluminum parts with new finish will be distinguished by new finish code V at the end of part number.
CURRENT
2017-06-26
Standard
AS4689D
Propose revision to add conductive high purity aluminum coating per MIL-DTL-83488 for aluminum alloy fittings. The W code aluminum parts with new finish will be distinguished by new finish code V at the end of part number.
CURRENT
2017-06-26
Standard
AS4691G
Propose revision to add conductive high purity aluminum coating per MIL-DTL-83488 for aluminum alloy fittings. The W code aluminum parts with new finish will be distinguished by new finish code V at the end of part number.
CURRENT
2017-06-26
Standard
AS5178B
Propose revision to add conductive high purity aluminum coating per MIL-DTL-83488 for aluminum alloy fittings. The W code aluminum parts with new finish will be distinguished by new finish code V at the end of part number.
CURRENT
2017-06-22
Standard
AMS6512H
This specification covers a premium aircraft-quality, maraging alloy steel in the form of bars, forgings, mechanical tubing, flash welded rings up through 10.000 inches (254.00 mm) inclusive in diameter or least distance between parallel sides and stock for forging or flash welded rings.
CURRENT
2017-06-22
Standard
AS893E
To Stabilize AS893D - issued 1-15-76 per MIL-F-18280 for O2 and GSE only; revised 4 times (12-1-83 to add O2 cleaning requirement and part id note, 1995-12 to reformat to SAE template and revised title, 2008-03 to add cad note, change proc spec to AS4842/2 and associated QML requirements, update matl inactive/can'd specs to active ones, revised wrench flat tolerances, and inactivated 'D' matl for new design, 2009-11 to update to current SAE template along with Table updates and add 'D' inactive effectivity date; reaffirmed twice; April 1983 & 2007-08. No other significant changes to the standard.
2017-06-22
WIP Standard
AS4200B
SCOPE IS UNAVAILABLE.
CURRENT
2017-06-22
Standard
AS6414A
This specification is applicable to the processes that are used in the manufacture of aerospace elastomer parts utilizing materials conforming to AMS7XXX series specifications, user specifications, or print on a Purchase Order (PO) that calls out this document for aerospace applications. The elastomer parts are in the form of O-rings, plate seals and other compression seals.
2017-06-22
WIP Standard
AS5714A
This SAE Aerospace Standard (AS) prescribes the Minimum Performance Standards (MPS) for wheel, brake, and wheel and brake assemblies to be used on aircraft certificated under 14 CFR Parts 23, 27, and 29. Compliance with this specification is not considered approval for installation on any aircraft.
CURRENT
2017-06-21
Standard
AMS2249H
This specification defines limits of variation for determining acceptability of the composition of cast or wrought titanium and titanium alloy parts and material acquired from a producer.
Viewing 1 to 30 of 21486

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