CHARACTERIZATION OF THE POST INJECTION BEHAVIOR OF GASOLINE DIRECT INJECTION FUEL INJECTORS

CHARACTERIZATION OF THE POST INJECTION BEHAVIOR OF GASOLINE DIRECT INJECTION FUEL INJECTORS PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
Abstract : The characteristics of gasoline sprayed directly into combustion chambers are of critical importance to engine out emissions and combustion system development. The optimization of the spray characteristics to match the in-cylinder flow field, chamber geometry, and spark location are vital tasks during the development of an engine combustion strategy. Furthermore, the presence of liquid fuel during combustion in Spark-Ignition (SI) engines causes increased hydrocarbon (HC) emissions [1]. Euro 6, LEVIII, and US Tier 3 emissions regulations reduce the allowable particulate mass significantly from the previous standards. LEVIII standards reduce the acceptable particulate emission to 1 mg/mile [2]. A good Direct Injection Spark Ignited (DISI) strategy vaporizes the correct amount of fuel at the proper point in the engine cycle with the proper in-cylinder air flow for optimal power output with minimal emissions. The opening and closing phases of DISI injectors is crucial to this task as the spray produces larger droplets during both theses phases. This work focuses on the results from a novel method to investigate fuel behavior upon closing of the fuel injector. A Design of Experiments (DOE) was used to determine the effect of pressure, temperature, and pulse-width of the fuel spray after the closing event. Experiments determined that the primary source of controlling the droplet size and the mass post injector closing for a given injector was the temperature. It was found that the end of injection behavior is a highly dynamic, complex event including, but not limited to, effects from the injector design, deposit concentration, and fuel type.

CHARACTERIZATION OF THE POST INJECTION BEHAVIOR OF GASOLINE DIRECT INJECTION FUEL INJECTORS

CHARACTERIZATION OF THE POST INJECTION BEHAVIOR OF GASOLINE DIRECT INJECTION FUEL INJECTORS PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
Abstract : The characteristics of gasoline sprayed directly into combustion chambers are of critical importance to engine out emissions and combustion system development. The optimization of the spray characteristics to match the in-cylinder flow field, chamber geometry, and spark location are vital tasks during the development of an engine combustion strategy. Furthermore, the presence of liquid fuel during combustion in Spark-Ignition (SI) engines causes increased hydrocarbon (HC) emissions [1]. Euro 6, LEVIII, and US Tier 3 emissions regulations reduce the allowable particulate mass significantly from the previous standards. LEVIII standards reduce the acceptable particulate emission to 1 mg/mile [2]. A good Direct Injection Spark Ignited (DISI) strategy vaporizes the correct amount of fuel at the proper point in the engine cycle with the proper in-cylinder air flow for optimal power output with minimal emissions. The opening and closing phases of DISI injectors is crucial to this task as the spray produces larger droplets during both theses phases. This work focuses on the results from a novel method to investigate fuel behavior upon closing of the fuel injector. A Design of Experiments (DOE) was used to determine the effect of pressure, temperature, and pulse-width of the fuel spray after the closing event. Experiments determined that the primary source of controlling the droplet size and the mass post injector closing for a given injector was the temperature. It was found that the end of injection behavior is a highly dynamic, complex event including, but not limited to, effects from the injector design, deposit concentration, and fuel type.

Direct Injection Gasoline Fuel Injector Characterization

Direct Injection Gasoline Fuel Injector Characterization PDF Author: Gasoline Fuel Injection Standards Committee
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

Get Book Here

Book Description
This SAE Recommended Practice promotes uniformity in the evaluation and qualification tests conducted on GDI fuel injectors used in gasoline engine applications, where fuel pressures are typically well above 1 MPa. The document scope is limited to electrically-actuated fuel injection devices used in automotive GDI systems and is primarily restricted to bench tests. The use of uniform and standardized testing and evaluation procedures for fuel injectors is important to the worldwide automotive community. Standardized test procedures provide both injector manufacturers and end-users with one accepted test for each of the key injector performance parameters, instead of a specialized test protocol for each of many customers and applications. The use of these procedures for test configurations, testing methods, data reduction and reporting that are contained in this document will significantly enhance the ability of one test laboratory to accurately repeat and verify the results of another.Gasoline direct injection (GDI) differs substantially from port fuel injection (PFI), hence the existing PFI recommended practice document (SAE J1832) cannot be employed. The application of GDI has rapidly expanded worldwide. Prior to this document, a recommended practice for GDI injectors was not available. This recommended practice will permit the automotive industry to evaluate, characterize and compare GDI hardware.

Fuel Injection Characteristics and Combustion Behavior of a Direct Injection Stratified Charge Engine

Fuel Injection Characteristics and Combustion Behavior of a Direct Injection Stratified Charge Engine PDF Author: Eric Norbert Balles
Publisher:
ISBN:
Category : Automobiles
Languages : en
Pages : 218

Get Book Here

Book Description


Flow Characteristics of Gas-blast Fuel Injectors for Direct-injection Compression-ignition Engines

Flow Characteristics of Gas-blast Fuel Injectors for Direct-injection Compression-ignition Engines PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description
Natural gas has a high auto-ignition temperature, therefore natural gas engines use an ignition source to promote combustion. The high-pressure direction-injection (HPDI) systems available use small diesel injections prior to the main gas injection. A new series of HPDI injectors have been developed that inject diesel and gas simultaneously through the same holes. In order to understand and control injection and combustion behavior in an engine, it is essential to understand how injection mass is related to the diesel/gas ratio and injection command parameters. Three prototype injectors are examined. "Prototype B" most closely resembles a standard J36 HPDI injector, but has a modified diesel needle that injects diesel internally into a common diesel/gas reservoir. Prototypes "CS & CSX" have the diesel needle eliminated and replaced with a flow restrictor. The pressure difference between the diesel and the gas controls the quantity of diesel injected. A single pulse width (GPW) for the gas needle controls the fuel quantities. An injection visualization chamber (IVC) was developed for flow measurements and optical characterization of injections into a chamber at pressures up to 80 bar. Diesel and natural gas are replaced by VISCOR® and nitrogen to study non-reacting flows. A novel feature of the IVC is a retracting shroud that allows the injector to reach steady-state prior to imaging. For low commanded injection duration (GPW less than 0.60 ms), the relation between GPW and injected mass is non-linear, for all injectors tested. For gas pulse widths greater than 0.65 ms the Co-injectors exhibit approximately linear behavior with higher diesel fuelling quantities lowering gas flow quantities. All Co-injectors are compared to baseline gas flow quantities of a standard J36 to show design difference effects on flow quantities. The sensitivity of gas flow to diesel in injection quantities, as well as the discharge coefficient are computed and theoretically modeled for each.

Development of Predictive Gasoline Direct Fuel Injector Model for Improved In-cylinder Combustion Characterization

Development of Predictive Gasoline Direct Fuel Injector Model for Improved In-cylinder Combustion Characterization PDF Author: Mohit Atul Mandokhot
Publisher:
ISBN:
Category : Automobiles
Languages : en
Pages : 117

Get Book Here

Book Description
Gasoline direct fuel injection systems have gained importance due to the increasing level of emissions regulation on SI combustion systems. Direct fuel injection delivery to cylinder provides better atomization and fuel mixing performance, enabling homogeneous mixture and better in-cylinder combustion. Increasing focus over the last few decades has been on better characterization of such gasoline direct fuel injection systems. Solenoid powered injectors act as actuators and enable accurate fuel delivery into the cylinder for a combustion event. Characterization of injector’s fuel delivery performance is an important aspect of achieving improved in-cylinder combustion performance. The objective of the current thesis is to develop a numerical physics based fuel injector model that provides a reliable prediction of flow rate and needle lift, in order to be used to improve in-cylinder combustion performance using 3D CFD model methodology. The developed model provides a reliable estimate of flow rate of developed injector, which is experimentally verified against instantaneous flow rate data provided by typical suppliers. In cases where inadequate prediction performance was noted, the errors arise out of lack of high fidelity electromagnetic modeling data, damping characteristics inside model and lack of geometry data to capture performance of highest accuracy.

Particle Image Velocimetry

Particle Image Velocimetry PDF Author: Markus Raffel
Publisher: Springer Science & Business Media
ISBN: 3540723072
Category : Technology & Engineering
Languages : en
Pages : 460

Get Book Here

Book Description
This immensely practical guide to PIV provides a condensed, yet exhaustive guide to most of the information needed for experiments employing the technique. This second edition has updated chapters on the principles and extra information on microscopic, high-speed and three component measurements as well as a description of advanced evaluation techniques. What’s more, the huge increase in the range of possible applications has been taken into account as the chapter describing these applications of the PIV technique has been expanded.

Analysis of Ignition Behavior in a Turbocharged Direct Injection Dual Fuel Engine Using Propane and Methane as Primary Fuels

Analysis of Ignition Behavior in a Turbocharged Direct Injection Dual Fuel Engine Using Propane and Methane as Primary Fuels PDF Author:
Publisher:
ISBN:
Category :
Languages : en
Pages :

Get Book Here

Book Description


Characterization of the Effects of Ducted Fuel Injection in a Compression Ignition Engine

Characterization of the Effects of Ducted Fuel Injection in a Compression Ignition Engine PDF Author: Christopher William Nilsen
Publisher:
ISBN:
Category :
Languages : en
Pages : 0

Get Book Here

Book Description
Ducted fuel injection (DFI) has been proposed as a strategy to enhance the fuel/charge-gas mixing within the combustion chamber of a direct-injection mixing-controlled compression-ignition engine. The concept involves injecting each fuel spray through a small tube within the combustion chamber to facilitate the creation of a leaner mixture in the autoignition zone, relative to a conventional free-spray configuration (i.e., a fuel spray that is not surrounded by a duct). This dissertation investigates the effects of ducted fuel injection on engine-out emissions and efficiency with two-orifice and four-orifice injector tips across a wide range of conditions. A numerical study contributes to the understanding of the fluid flow effects of DFI. The experiments in chapter two use a two-orifice fuel injector to test two duct configurations relative to conventional diesel combustion. The result is that DFI is confirmed to be effective at curtailing engine-out soot emissions. It also breaks the tradeoff between emissions of soot and nitrogen oxides (NO[subscript x]) by simultaneously attenuating soot and NO[subscript x] with increasing dilution. The third chapter expands on the second by comparing ducted fuel injection to conventional diesel combustion over a wide range of operating conditions and at higher loads (up to 8.7 bar gross indicated mean effective pressure) with a four-orifice fuel injector. This chapter is achieved through sweeps of intake-oxygen mole-fraction, injection duration, intake pressure, start of combustion timing, fuel-injection pressure, and intake temperature. Ducted fuel injection is shown to curtail engine-out soot emissions at all tested conditions. Under certain conditions, ducted fuel injection can attenuate engine-out soot by over a factor of 100. In addition to producing significantly lower engine-out soot emissions, ducted fuel injection enables the engine to be operated at low-NO[subscript x] conditions that are not feasible with conventional diesel combustion due to high soot emissions. The fourth chapter explores 1.1 bar IMEP[subscript g] (low load) conditions and 10 bar IMEP[subscript g] (higher-load) conditions with the same four-orifice fuel injector as in chapter three. DFI and CDC are directly compared at each operating point in the study. At the idle condition, the intake dilution was swept to elucidate the soot and NO[subscript x] performance of DFI in this new load range. This expands the range of conditions over which DFI has been shown to attenuate soot formation. It also shows that DFI enables low-NO[subscript x], low-load operation that is not achievable with CDC due to excessive soot formation at high dilution levels. The fifth chapter uses a numerical model to develop the understanding of the fluid flow effects of DFI. This enabled studies of entrainment and mixing that would have been much more challenging to do in an experiment. This showed that DFI enhances charge gas entrainment before the duct and blocks entrainment inside of the duct. Mixing is enhanced by the duct, which resulted in lower peak equivalence ratios at the end of the duct.

Automotive Spark-Ignited Direct-Injection Gasoline Engines

Automotive Spark-Ignited Direct-Injection Gasoline Engines PDF Author: F. Zhao
Publisher: Elsevier
ISBN: 008055279X
Category : Technology & Engineering
Languages : en
Pages : 129

Get Book Here

Book Description
The process of fuel injection, spray atomization and vaporization, charge cooling, mixture preparation and the control of in-cylinder air motion are all being actively researched and this work is reviewed in detail and analyzed. The new technologies such as high-pressure, common-rail, gasoline injection systems and swirl-atomizing gasoline fuel injections are discussed in detail, as these technologies, along with computer control capabilities, have enabled the current new examination of an old objective; the direct-injection, stratified-charge (DISC), gasoline engine. The prior work on DISC engines that is relevant to current GDI engine development is also reviewed and discussed. The fuel economy and emission data for actual engine configurations have been obtained and assembled for all of the available GDI literature, and are reviewed and discussed in detail. The types of GDI engines are arranged in four classifications of decreasing complexity, and the advantages and disadvantages of each class are noted and explained. Emphasis is placed upon consensus trends and conclusions that are evident when taken as a whole; thus the GDI researcher is informed regarding the degree to which engine volumetric efficiency and compression ratio can be increased under optimized conditions, and as to the extent to which unburned hydrocarbon (UBHC), NOx and particulate emissions can be minimized for specific combustion strategies. The critical area of GDI fuel injector deposits and the associated effect on spray geometry and engine performance degradation are reviewed, and important system guidelines for minimizing deposition rates and deposit effects are presented. The capabilities and limitations of emission control techniques and after treatment hardware are reviewed in depth, and a compilation and discussion of areas of consensus on attaining European, Japanese and North American emission standards presented. All known research, prototype and production GDI engines worldwide are reviewed as to performance, emissions and fuel economy advantages, and for areas requiring further development. The engine schematics, control diagrams and specifications are compiled, and the emission control strategies are illustrated and discussed. The influence of lean-NOx catalysts on the development of late-injection, stratified-charge GDI engines is reviewed, and the relative merits of lean-burn, homogeneous, direct-injection engines as an option requiring less control complexity are analyzed.

Automotive Gasoline Direct-Injection Engines

Automotive Gasoline Direct-Injection Engines PDF Author: Fuquan Zhao
Publisher: SAE International
ISBN: 0768008824
Category : Technology & Engineering
Languages : en
Pages : 372

Get Book Here

Book Description
This book covers the latest global technical initiatives in the rapidly progressing area of gasoline direct injection (GDI), spark-ignited gasoline engines and examines the contribution of each process and sub-system to the efficiency of the overall system. Including discussions, data, and figures from many technical papers and proceedings that are not available in the English language, Automotive Gasoline Direct Injection Systems will prove to be an invaluable desk reference for any GDI subject or direct-injection subsystem that is being developed worldwide.