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2015-04-14
Journal Article
2015-01-0918
Daniel Duke, Andrew Swantek, Alan Kastengren, Kamel Fezzaa, Christopher Powell
Abstract Cavitation plays an important role in fuel injection systems. It alters the nozzle's internal flow structure and discharge coefficient, and also contributes to injector wear. Quantitatively measuring and mapping the cavitation vapor distribution in a fuel injector is difficult, as cavitation occurs on very short time and length scales. Optical measurements of transparent model nozzles can indicate the morphology of large-scale cavitation, but are generally limited by the substantial amount of scattering that occurs between vapor and liquid phases. These limitations can be overcome with x-ray diagnostics, as x-rays refract, scatter and absorb much more weakly from phase interfaces. Here, we present an overview of some recent developments in quantitative x-ray diagnostics for cavitating flows. Measurements were conducted at the Advanced Photon Source at Argonne National Laboratory, using a submerged plastic test nozzle.
2015-04-14
Technical Paper
2015-01-0923
Mohamed Chouak, Alexandre Mousseau, Damien Reveillon, Louis Dufresne, Patrice Seers
Abstract The transient characteristics of the internal flow dominate all the ensuing processes: spray, fuel-air mixture formation as well as combustion and pollutants formation. Therefore, it is crucial to understand the dynamics of the injectors' internal flow. The objective of this work is to study all transient effects that may impact the internal flow of a single hole injector under different conditions. Since the numerical investigation of such a complex flow is hampered by several factors for the real operating conditions-namely the turbulence, the cavitation and the needle motion-this work is divided into two parts. In the first part, only the effects of turbulence and cavitation are considered through the study of the effects of the fuel properties as well as the injection conditions at the fully open needle position. The impact of these effects is studied by means of the Reynolds and the cavitation number.
2015-04-14
Technical Paper
2015-01-0921
Raul Payri, Jaime Gimeno, Pedro Marti-Aldaravi, Marcos Carreres
Abstract Proper initial conditions are essential to successfully perform a simulation, especially for highly transient problems such as Diesel spray injection. Until now, no much attention has been paid to the internal nozzle flow initialization because spray simulations are usually decoupled from the nozzle. However, new homogeneous models like Eulerian Spray Atomization (ESA) model allow to simulate the internal nozzle flow and the spray seamlessly. Therefore, the behavior of the spray for the first microseconds is highly influenced by the initial conditions inside the nozzle. Furthermore, last experiments confirm the presence of gas inside the nozzle between successive injections. This work deals with the initialization procedure in a way that mass flow rate and spray penetration curves are well predicted by the model.
2015-04-14
Journal Article
2015-01-0892
Alastair Smith, Rod Williams
Abstract The formation of deposits within injector nozzle holes of common-rail injection fuel systems fitted to modern diesel cars can reduce and disrupt the flow of fuel into the combustion chamber. This disruption in fuel flow results in reduced or less efficient combustion and lower power output. Hence there is sustained interest across the automotive industry in studying these deposits, with the ultimate aim of controlling them. In this study, we describe the use of Scanning Electron Microscopy (SEM) imaging to characterise fuel injector hole deposits at intervals throughout an adaptation of the CEC Direct Injection Common Rail Diesel Engine Nozzle Coking Test, CEC F-98-08 (DW10B test)[1]. In addition, a similar adaptation of a previously published Shell vehicle test method [2] was employed to analyse fuel injector hole deposits from a fleet of Euro 5 vehicles.
2015-04-14
Technical Paper
2015-01-0911
Juliane Wetzel, Michael Henn, Mark Gotthardt, Hermann Rottengruber
Abstract The optimization of the mixture formation represents great potential to decrease fuel consumption and emissions of spark-ignition engines. The injector and the nozzle are of major importance in this concern. In order to adjust the nozzle geometry according to the requirements an understanding of the physical transactions in the fuel spray is essential. In particular, the primary spray break-up is still described inadequately due to the difficult accessibility with optical measuring instruments. This paper presents a methodology for the characterization of the nozzle-near spray development, which substantially influences the entire spray shape. Single hole injectors of the gasoline direct injection (GDI) with different nozzle hole geometries have been investigated in a high pressure chamber by using the MIE scattering technique. To examine the spray very close to the nozzle exit a long-distance microscope in combination with a Nd:YAG-laser was used.
2015-04-14
Technical Paper
2015-01-0944
Maryam Moulai, Ronald Grover, Scott Parrish, David Schmidt
Abstract A computational and experimental study was performed to characterize the flow within a gasoline injector and the ensuing sprays. The computations included the effects of turbulence, cavitation, flash-boiling, compressibility, and the presence of non-condensible gases. The flow domain corresponded to the Engine Combustion Network's Spray G, an eight-hole counterbore injector operating in a variety of conditions. First, a rate tube method was used to measure the rate of injection, which was then used to define inlet boundary conditions for simulation. Correspondingly, injection under submerged conditions was simulated for direct comparison with experimental measurements of discharge coefficient. Next, the internal flow and external spray into pressurized nitrogen were simulated under the base spray G conditions. Finally, injection under flashing conditions was simulated, where the ambient pressure was below the vapor pressure of the fuel.
2015-04-14
Technical Paper
2015-01-0948
Le (Emma) Zhao, Ahmed Abdul Moiz, Jeffrey Naber, Seong-Young Lee, Sam Barros, William Atkinson
Abstract High-speed spray-to-spray liquid impingement could be an effective phenomenon for the spray propagation and droplet vaporization. To achieve higher vaporization efficiency, impingement from two-hole nozzles is analyzed in this paper. This paper focuses on investigating vaporization mechanism as a function of the impingement location and the collision breakup process provided by two-hole impinging jet nozzles. CFD (Computational Fluid Dynamics) is adopted to do simulation. Lagrangian model is used to predict jet-to-jet impingement and droplet breakup conditions while KH-RT breakup and O'Rourke collision models are implemented for the simulation. The paper includes three parts: First, a single spray injected into an initially quiescent constant volume chamber using the Lagrangian approach is simulated to identify the breakup region, which will be considered as a reference to study two-hole impinging jet nozzles.
2015-04-14
Technical Paper
2015-01-0949
Mathis Bode, Tobias Falkenstein, Vincent Le Chenadec, Seongwon Kang, Heinz Pitsch, Toshiyuki Arima, Hiroyoshi Taniguchi
Abstract Compared to conventional injection techniques, Gasoline Direct Injection (GDI) has a lot of advantages such as increased fuel efficiency, high power output and low emission levels, which can be more accurately controlled. Therefore, this technique is an important topic of today's injection system research. Although the operating conditions of GDI injectors are simpler from a numerical point of view because of smaller Reynolds and Weber numbers compared to Diesel injection systems, accurate simulations of the breakup in the vicinity of the nozzle are very challenging. Combined with the complications of experimental techniques that could be applied inside the nozzle and at the nozzle exit, this is the reason for the lack of understanding the primary breakup behavior of current GDI injectors.
2015-04-14
Journal Article
2015-01-0779
Gerald Gentz, Bryce Thelen, Paul Litke, John Hoke, Elisa Toulson
Abstract Turbulent jet ignition is a pre-chamber ignition enhancement method that produces a distributed ignition source through the use of a chemically active turbulent jet which can replace the spark plug in a conventional spark ignition engine. In this paper combustion visualization and characterization was performed for the combustion of a premixed propane/air mixture initiated by a pre-chamber turbulent jet ignition system with no auxiliary fuel injection, in a rapid compression machine. Three different single orifice nozzles with orifice diameters of 1.5 mm, 2 mm, and 3 mm were tested for the turbulent jet igniter pre-chamber over a range of air to fuel ratios. The performance of the turbulent jet ignition system based on nozzle orifice diameter was characterized by considering both the 0-10 % and the 10-90 % burn durations of the pressure rise due to combustion.
2015-04-14
Technical Paper
2015-01-1371
Samuel T. Bartlett
Abstract With the many model variations produced on the same production line because of increasing power train options, fuel efficiency targets, performance and customer demands we saw limitations with our existing suspension mount equipment. Layout options were limited due to guided shifts and transfers. Large supporting frame work took up valuable floor space. Model wheelbase sizes and suspension pallets were limited to the model requirements of the original equipment. We needed an adaptable system to install the engine/front suspension assemblies and the rear suspension assemblies. We found a solution by utilizing the capabilities of 6-axis industrial robots to make the core components of the equipment simpler; many of the functions of a traditional machine can now be accomplished by the robot. We were able to vary install position to optimize handling characteristics and accommodate the model-to-model varieties on the same production line.
2015-03-30
Technical Paper
2015-01-0126
Meng Choung Chiong, Srithar Rajoo, Alessandro Romagnoli
Abstract This paper presents a concept for new piston expander utilizing nozzle as part of a secondary steam cycle to recover exhaust energy. A commercial 1D simulation tool, AVL BOOST, was used to model the system, and comparison study was carried out between the conventional and nozzle piston expanders. It was found the nozzle piston expander could increase output power from a minimum of 0.73kW up to a maximum of 4.75kW. The simulation study has shown that the concept of using nozzle to admit steam into the piston expander has potential to improve engine system level efficiency.
2015-03-29
Standard
AS4311A
SCOPE IS UNAVAILABLE.
2015-03-29
Standard
AS4310A
SCOPE IS UNAVAILABLE.
2015-03-29
Standard
AS4309D
SCOPE IS UNAVAILABLE.
2015-03-27
Standard
J1254_201503
This SAE Standard includes names of major components and parts peculiar to this type of machine. Illustrations used here are not intended to include all existing commercial machines or be exactly descriptive of any particular machine. They have been provided to describe the principles to be used in applying this document.
2015-03-25
WIP Standard
AS5828A
No scope available.
2015-03-24
Standard
AMS4904C
This specification covers a titanium alloy in the form of sheet, strip, and plate up through 2.000 inches (50.80 mm), inclusive.
2015-03-24
Standard
AMS4115J
This specification covers an aluminum alloy in the form of rolled or cold-finished bars, rods, and wire, of flash welded rings, and of stock for flash welded rings.
2015-03-24
Standard
AMS4116J
This specification covers an aluminum alloy in the form of bars, rods, and wire.
2015-03-24
Standard
AMS4903C
This specification covers a titanium alloy in the form of sheet strip, and plate up through 2.000 inches (50.80 mm), inclusive.
2015-03-24
Standard
AMS4901T
This specification covers one grade of commercially-pure titanium in the form of sheet, strip, and plate up through 1.000 inch (25.40 mm), inclusive.
Viewing 31 to 60 of 15616

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