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Training / Education

Fundamentals of Automotive Fuel Delivery Systems

The key to a vehicle's overall operation is the superior, quality design of its major moving subsystems. Automotive gasoline and diesel fuel delivery systems in particular must be virtually malfunction free for all components for the entire vehicle prescribed service life. Fuel systems must be robust and precise enough to store and deliver the appropriate amount of fuel to power the engine. These stringent requirements necessitate a basic understanding of the subsystem working principles, functionalities and interrelated components.
Training / Education

Liquid Atomization, Sprays, and Fuel Injection

Liquid fuel atomization and spray formation is the heart of the majority of stationary and mobile power generation machines that we rely on. This seminar focuses on the process of liquid atomization and spray formation and how it relates to fuel injection systems and emission of pollutants in modern engines. The seminar begins with background coverage of terminology, the purposes of liquid atomization and spray formation, and different designs of atomizers and nozzles employed in various industries.
Training / Education

Fundamentals of Threaded Fasteners

Fastener experts believe that upwards of 95% of all fastener failures are the result of either the wrong fastener for the job or improper installation. Whether this shocking figure is accurate or not, it is irrefutable that threaded fasteners are poorly misunderstood by many in both the fastener and user communities. In October 1990 the USS Iwo Jima suffered a catastrophic steam valve accident minutes after leaving port following repairs to its steam plant. In one of the single most deadly events of Operation Desert Storm, ten of the eleven crewmen present in the engine compartment would lose their lives.
Training / Education

Fuel Systems Material Selection and Compatibility with Alternative Fuels

This course will introduce the participants to the factors governing fuel-material compatibility and methods to predict and empirically determine compatibility for new alternative fuel chemistries. By understanding the mechanisms and factors associated with chemically-induced degradation, participants will be able to assess the impact of fuel chemistry to infrastructure components, including those associated with vehicle fuel systems. This course is unique in that it looks at compatibility from a fuel chemistry perspective, especially new fuel types such as alcohols and other biofuels.
Training / Education

Introduction to Rubber Science and Technology

Rubber – a loosely cross-linked network of polymer chains that when strained to high levels will forcibly return to at or near it original dimensions. This course is designed to provide the participant with a thorough understanding of rubber’s engineering characteristics. This class will introduce the various sources of rubber, both natural and synthetic. The class will contrast the differences between rubber and plastics; including thermoplastic rubber. Detailed discussions on how to select the correct rubber polymer for the application, highlighting the pros and cons of each major rubber type.
Training / Education

Basics of Silicone Rubber Science and Technology

Silicone rubber is comprised of inorganic-organic polymers. These materials consist of an inorganic backbone with organic side groups attached to silicon atoms. This family of polymers possesses unmatched versatility giving the formulator and user multiple forms and methods to cross link the polymers into rubber materials having the widest service temperature range of any rubber material. This course is designed to provide the participant with a thorough understanding of silicone’s engineering characteristics.
Training / Education

Critical Concepts of Tolerance Stacks ASME Y14.5 -1994 & 2009 Advanced Level

2021-07-13
This 3-day advanced-level course provides an in-depth explanation of how to use tolerance stacks to analyze product designs and how to use geometric tolerances in stacks. The course can be conducted in three eight-hour sessions or with flexible scheduling, including five mornings or five afternoons.  You’ll learn the essential methods and concepts used for creating 1D part and assembly tolerance stacks. The course discusses how virtual condition affects part assembly, stack methods, and using the stack form and spreadsheet.
Technical Paper

Calculation of Inhomogeneous-Charge Combustion in a Swirl-Assisted Lean-Burn Engine

1991-02-01
910266
A multidimensional computational method is extended to include the methodology for modelling of partially-mixed inhomogeneous charge combustion and is applied to investigation of combustion and simultaneous mixing process of an inhomogeneous mixture in a lean-burn spark-ignition engine. The in-cylinder flow and charge mixture distribution pertain to a helical intake port with manifold fuel injection, and were obtained through complete simulation of the induction and compression processes. The engine compression ratio is 12:1 and the study pertains to the operating condition of 2500 rpm. The results show that the flow and charge distribution at the time of ignition is predominantly characterised by the evolution of the induction flow. The effect of heat release on enhancement of charge mixing is marginal and the pre-ignition charge distribution is preserved throughout the combustion.
Technical Paper

Numerical Simulation of Swirling Port-Valve-Cylinder Flow in Diesel Engines

1991-02-01
910263
A CAD/CAE procedure has been used for the analysis of the flow in an intake port-valve-cylinder assembly of a DI Diesel engine. The flow was simulated for both, steady state conditions and transient motored situation during intake and compression strokes. The characteristics of the helical port are analyzed, for the steady state case, in terms flow rate, generation of angular momentum flux and induced in-cylinder flow motion. The results of the simulation were correlated with experimental results, consisting of oil film visualizations on valve and intake port surfaces, and of local velocity measurements in the cylinder. The transient flow simulation shows the different characteristics of the flow motion in cylinder and piston bowl during intake and compression strokes. It was observed that the swirl generating capacity of the valve is different between the valve opening and closing phases.
Technical Paper

A PC Engine Control Development System

1991-02-01
910259
Given the rather complicated set of coordinated control inputs which are necessary to control a spark ignition engine, primary control system development and evaluation can be a very difficult task. It is also difficult to develop microprocessor systems which are flexible enough for rapid system reconfiguration. In this paper it is shown that a Personal Computer (PC) provides an excellent solution to this common problem. Possible execution time problems are avoided by the use of a special multitasking environment and simple external hardware. The external hardware takes care of the cycle to cycle fueling and spark advance timing calculations. The PC itself uses its execution time only for calculating new fueling pulse widths and spark advance angles when the operating point of the engine changes. There is also extra computing capacity available for system simulations, condition monitoring, fault detection or perhaps driver information.
Technical Paper

Development of New Electronically Controlled Fuel Injection System ECD-U2 for Diesel Engines

1991-02-01
910252
To meet the 1990s' requirements for diesel engines, the realization of innovative fuel injection system has been expected. Thus the fuel injection system named ECD-U2 was newly developed. ECD-U2 is the electronic unit injector system with high pressure common rail of which features are explained as follows; Fully electronic and flexible control in fuel quantity and injection timing. Adjustable injection rate shape Optimum injection pressure control Superior packageability and low drive torque loss. In this paper, design strategies, actual hardware configurations and some test results of ECD-U2 are described.
Technical Paper

Climate Control for Electric Vehicles

1991-02-01
910250
The vast majority of cars and small trucks are sold with factory installed air conditioning (approximately 80% in 1989). For electric vehicles to succeed in the marketplace, air conditioning will need to be offered as optional equipment, along with adequate heating and defrosting systems. While providing the level of cooling performance expected by vehicle operators, it is important that the power consumption of the air conditioning systems used in electric vehicles be minimized, to minimize penalties to vehicle range and performance. This paper summarizes the design and performance of several air conditioning systems that have been developed for electric vans over the past two years, including systems based largely on standard automobile air conditioning components and more advanced systems using high performance heat transfer components and a variable speed refrigerant compressor.
Technical Paper

A High Torque, High Efficiency CVT for Electric Vehicles

1991-02-01
910251
Epilogics, a young engineering firm in Los Gatos, CA, has developed the first fully geared, high torque, high efficiency, infinitely variable transmission suitable for automotive applications. The IVT has particular significance to electric vehicles because it can provide a highly efficient, yet exceptionally controllable means to regenerate power throughout the normal braking cycle (allowing regeneration even at near-zero vehicle speeds). Under normal operating conditions, the efficiency of the Epilogics transmission exceeds 90% as derived mathematically and corroborated experimentally. The device does not rely on traction to transmit torque and can therefore match the torque capacity of any typical gear drive. The size, weight, and cost of the device closely approximates that of a four-speed transmission suitable for the application.
Technical Paper

Sliding Surface Profiling of Plain Journal Bearings

1991-02-01
910158
Several cases of rod bearing shells assembled in highly loaded engines have been reported to show premature wear of the sliding surface, more specifically the electroplated lead-tin overlay. To understand these phenomena and overcome such occurrences, an analytical method has been developed to simulate the operation of specially designed journal bearings featuring circumferential profiling of the sliding surface. The resulting computer program solves the Reynolds equation taking into account a non-circular bearing surface, thus allowing for a customized design which extends operational component life through minimum oil film thickness (MOFT) increase and peak oil film pressure (POFP) and bearing back temperature (BBT) reduction. Theoretical results show an effective way to prevent premature wear.
Technical Paper

Engine Bearing Contact Pressure Simulations with Thermal Effects

1991-02-01
910159
A numerical procedure to determine the contact pressure between the engine bearing and block is presented in this paper. As examples, the pressure distributions for both the cast iron and aluminum blocks are calculated. The variations of the contact pressures at different temperatures are also studied. Numerical results indicate that the retention of the bearing is accomplished primarily by the high contact pressure around the bearing edges for grooved bearings. A force diagram explaining this phenomenon is provided. In addition, a simple equation evolving from elasticity theory is included for a quick determination of the contact pressure.
Technical Paper

A Study of Oil Flow and Temperature in Journal Bearings

1991-02-01
910160
With the recent trend toward increased unit load in engine bearings, problems due to lack of lubrication frequently arise, especially in crankpin bearings. We have previously investigated the influence of shaft and bearing design on the oil flow using the connecting rod in actual use under alternating loads. In this paper, we investigate the critical value of oil flow at which the Fbearing temperature rises rapidly and the influence of connecting rod rigidity on the oil flow. As a result of these tests, it was discovered that the increase in bearing temperature (ΔTj) is in inverse proportion to oil flow (Qj),tests resulting in a single curve expressed by ΔTj = E1/Qj + E2, that the critical oil flow (Qc) varies according to Qc = Const. • E1, and that connecting rod rigidity greatly influences the oil flow (specifically, the greater the rigidity, the less oil).
Technical Paper

Biaxial Torsion-Bending Fatigue of SAE Axle Shafts

1991-02-01
910164
Variable amplitude torsion, bending, and combined torsion and bending fatigue tests were performed on an axle shaft. The moment inputs used were taken from the respective history channels of a cable log skidder vehicle axle. Testing results indicated that combined variable amplitude loading lives were shorter than the lives of specimens subjected to bending or torsion alone. Calculations using strain rosette readings indicated that principle strains were most active around specific angles but also occurred with lesser magnitudes through a wider angular range. Over the course of a biaxial test, cyclic creep narrowly limited the angles and magnitudes of the principal strains. This limitation was not observed in the calculated principal stress behavior. Simple life predictions made on the measured strain gage histories were non-conservative in most cases.
Technical Paper

Development of Three Layers Copper-Lead Bearings for Higher Speed Automotive Engines

1991-02-01
910161
As the recent automotive engines are designed for higher performance, the rotating speed of the engines have been increased drastically. Therefore the engine bearings should be further improved to have better anti-seizure and wear properties under the high temperature at the high rotating speed. The authors have analyzed the necessary functions of the three layers copper-lead bearings at such operating conditions, and then improved and developed the overlay and the copper based bearing alloy with steel back. Physical and chemical properties for this new bearing were studied. Then the bearing performance tests were carried out including the high speed seizure tests and engine tests. From these test results, it was confirmed that this new bearing could be applied for the recent very high speed automotive engines.
Technical Paper

Fuel Injectors in Diesels With Large Needle-Barrel Clearance

1991-02-01
910183
An attempt to operate a diesel engine using the so-called hydraulic fuel injector with large clearance between the needle and its barrel was carried out experimentally. In this type of injectors, the spring force was substituted by a pressurized hydraulic oil to control the needle motion. Various factors affecting the injection system, for both hydraulically and spring loaded injectors, were also theoretically simulated and tested. The present study confirmed. according to both the experimental and theoretical results, that the use of hydraulic closer of needles is a promising technique to overcome the problem of diesel engine operation with large needle clearance (7 times the standard). To maintain the best specific fuel consumption by the engine, the injection timing has to be readjusted in accordance with the increase in the needle clearance.
Technical Paper

Advanced In-Line Pump for Medium-Duty Diesel Engines to Meet Future Emissions Regulations

1991-02-01
910182
This paper describes the Nippondenso in-line pump system designed for U.S. 1991 emissions regulation for medium duty diesel engines. With the combined use of the further improved in-line pump, NB-S and the multi-hole nozzle with a smaller orifice diameter, the required injection pressure of 100 MPa to 120 MPa at the nozzle can be achieved. However, some problems to be resolved exist in the subject fuel injection system: (1) secondary injection, (2) cavitation erosion of injection pipe, (3) higher pressure sealing of fuel, (4) undesirable fuel delivery curve vs. pump speed (called “Trumpet Shape” fuel delivery curve) Thus technical measures to cope with those problems are explained in details.
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