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Turbocharging Internal Combustion Engines

The need to control emissions and maintain fuel economy is driving the use of advanced turbocharging technology in both diesel and gasoline engines. As the use of diesel engines in passenger car gasoline and diesel engines increases, a greater focus on advanced turbocharging technology is emerging in an effort to reap the benefits obtained from turbocharging and engine downsizing. This seminar covers the basic concepts of turbocharging of gasoline and diesel engines (light and heavy duty), including turbocharger matching and charge air and EGR cooling, as well as associated controls.

High Efficiency IC Engines, 2012

The 14 papers in this technical paper collection discuss high efficiency IC engines. Topics covered include engine downsizing, pressure boosting and turbocharging, intelligent combustion, low temperature and stratified charge, advanced fuel injection technologies, and more. The 15 papers in this technical paper collection discuss high efficiency IC engines. Topics covered include engine downsizing, pressure boosting and turbocharging, intelligent combustion, low temperature and stratified charge, advanced fuel injection technologies, and more.

Engine Boosting Systems, 2018

The papers in this collection cover conceptual, modeling, and experimental studies relating to advanced turbochargers/superchargers and advanced boosting systems to achieve increased power density, better fuel economy, and reduced emissions.

Engine Boosting Systems, 2017

The papers in this collection cover conceptual, modeling, and experimental studies relating to advanced turbochargers/superchargers and advanced boosting systems to achieve increased power density, better fuel economy, and reduced emissions.

High Load HCCI Operation Using Different Valving Strategies in a Naturally-Aspirated Gasoline HCCI Engine

This session focuses on kinetically controlled combustion. Experimental and simulation studies pertaining to various means of controlling combustion are welcome. Examples are research studies dealing with temperature and composition distribution inside the cylinder and their impact on heat release process. Studies clarifying the role of fuel physical and chemical properties in autoignition are also welcome. Presenter Hanho Yun, General Motors Company

Spotlight on Design: Sensors: Miniaturization and Testing

“Spotlight on Design” features video interviews and case study segments, focusing on the latest technology breakthroughs. Viewers are virtually taken to labs and research centers to learn how design engineers are enhancing product performance/reliability, reducing cost, improving quality, safety or environmental impact, and achieving regulatory compliance. Accurate data is critical for the testing and development of parts and systems for cars, trucks, and airplanes. To obtain this data, engineers rely on high-end specialty sensors that can fit into cramped spaces and operate reliably under extreme heat and pressure. In the episode “Sensors: Miniaturization and Testing” (21:02), AVL engineers explain how a new crystalline material was developed to accurately measure the high pressures in the combustion chamber of turbocharged engines, and Meggitt Sensing Systems profiles the world’s smallest triaxial IEPE accelerometer.

Development of High-Efficiency Rotary Engines

Combustion engines are typically only 20-30% efficient at part-load operating conditions, resulting in poor fuel economy on average. To address this, LiquidPiston has developed an improved thermodynamics cycle, called the High-Efficiency Hybrid Cycle (HEHC), which optimizes each process (stroke) of the engine operation, with the aim of maximizing fuel efficiency. The cycle consists of: 1) a high compression ratio; 2) constant-volume combustion, and 3) over-expansion. At a modest compression ratio of 18:1, this cycle offers an ideal thermodynamic efficiency of 74%. To embody the HEHC cycle, LiquidPiston has developed two very different rotary engine architectures ? called the ?M? and ?X? engines. These rotary engine architectures offer flexibility in executing the thermodynamics cycle, and also result in a very compact package. In this talk, I will present recent results in the development of the LiquidPiston engines. The company is currently testing 20 and 40 HP versions of the ?M?
Technical Paper

Analytical Prediction of Acoustic Emissions From Turbocharger Bearings

Turbochargers are progressively used in modern automotive engines to enhance engine performance and reduce energy loss and adverse emissions. Use of turbochargers along with other modern technologies has enabled development of significantly downsized internal combustion engines. However, turbochargers are major sources of acoustic emissions in modern automobiles. Their acoustics has a distinctive signature, originating from fluid-structure interactions. The bearing systems of turbochargers also constitute an important noise source. In this case, the acoustic emissions can mainly be attributed to hydrodynamic pressure fluctuations of the lubricant film. The developed analytical model determines the lubricant pressure distribution in the floating journal bearings used mainly in the modern turbocharges. This allows for an estimation of acoustic emissions.
Technical Paper

NVH Comfort of Range Extenders for Electric Vehicles

The most appreciated driving characteristics of electric vehicles are the quietness and spontaneous torque rise of the powertrain. The application of range extenders (REX) with internal combustion engines (ICEs) to increase the driving range is a favourable solution regarding costs and weight, especially in comparison with larger battery capacities. However, the NVH integration of a REX is challenging, if the generally silent driving characteristics of electric vehicles shall remain preserved. This paper analyses key NVH aspects for a REX design and integration to fulfil the high expectations regarding noise and vibration comfort in an electric vehicle environment. The ICE for a REX is typically dimensioned for lower power outputs, incorporating a low number of cylinder units, which is even more challenging concerning the NVH integration. The basic REX concept is evaluated by considering power and fuel efficiency demands in combination with an interior noise forecast.
Technical Paper

Reinforcement of Low-Frequency Sound by Using a Panel Speaker Attached to the Roof Panel of a Passenger Car

The woofer in a car should be large to cover the low frequencies, so it is heavy and needs an ample space to be installed in a passenger car. The geometry of the woofer should conform to the limited available space and layout in general. In many cases, the passengers feel that the low-frequency contents are not satisfactory although the speaker specification covers the low frequencies. In this work, a thin panel is installed between the roof liner and the roof panel, and it is used as the woofer. The vibration field is controlled by many small actuators to create the speaker and baffle zones to avoid the sound distortion due to the modal interaction. The generation of speaker and baffle zones follows the inverse vibro-acoustic rendering technique. In the actual implementation, a thin acrylic plate of 0.53ⅹ0.2 m2 is used as the radiator panel, and the control actuator array is composed of 16 moving-coil actuators.
Technical Paper

Advanced Methods to Handle LSPI in TGDI Engines

In order to meet the stringent emission norms like EU6 and EU7 together with CAFÉ/CAFC norms, down-sizing of the engine is one of the thrust areas of focus among the OEMs. To this end, keeping the engine size small but to achieve the required power output, advanced Turbo charged Gasoline Direct Injection engine technology (TGDI) has emerged. However, TGDI technology is susceptible to an abnormal combustion phenomenon termed as Low Speed Pre-Ignition (LSPI) event. This event happens prior to the intended combustion, which causes the catastrophic engine damage. Several studies in terms of simulation and experiments to understand this phenomenon are reported in the literature. The main factors influencing this occurrence are found to be engine design and calibration, fuel types and engine oil formulation (in terms of calcium content).
Technical Paper

Thermal Analysis of Clutch Assembly Using Co-Simulation Approach

Automotive clutches are rotary components which transmits the torque from the engine to the transmission. During the engagement, due to the difference in speed of the shafts the friction lining initially slips until it makes a complete engagement. Enormous amount of heat is generated due to the slippage of the friction lining, leading to poor shift quality and clutch failure. Depending on the road & traffic conditions, and frequency of engagement and disengagement of the clutch, it generates transient heating and cooling cycles. Hill fade test with maximum GVW conditions being the worst case scenario for the clutch. A test was conducted to understand the performance of the clutch, in which clutch burning was observed. The clutch lining got blackened and burning smell was perceived. The friction coefficient drops sharply to a point until it cannot transmit the torque required to encounter the slope. This further worsen clutch slippage and lead to more severe temperature rise.
Technical Paper

Dynamic Behavior of In-Cylinder Pressure Causing Fatigue Failure of Reed Valves

Numerous studies considering interaction between refrigerant and reed valve motion in positive displacement compressors have been cited in literature. CFD and FEA simulation tools have allowed modeling of fully coupled interaction of fluids and moving parts [1]. The present paper describes a simplified model of a multi-cylinder reciprocating piston compressor and estimation of pressure surge at high compressor speeds. The results show that the delayed discharge valve opening and closing causes surge in pressures due to formation of pressure waves. For the chosen geometry and operating conditions in the present paper, the characteristic travel time of such waves is much shorter (~ 0.2ms) as compared to longer response time of reed valves (> 1ms) owing to stiffness and exhibit delayed opening due to others factors too like stiction effect. These pressure surges may exceed the fatigue limit of reed valves and cause failures.
SAE MOBILUS Subscription

SAE International Journal of Passenger Cars—Mechanical Systems

Editor-in-Chief: Dr. Mohamed El-Sayed, Eastern Michigan University, USA Indexed in ESCI (Emerging Sources Citation Index, Web of Science) Engineering Village (Ei Compendex) Scopus 1.9 2019CiteScore 59th percentile Powered by Author Resources Call for Papers Library Recommendation Form Published Volumes Subscription Options Aims and Scope The SAE International Journal of Passenger Cars—Mechanical Systems is the predominant scholarly publication for research and developments relating to the mechanical systems of light-duty, on-road passenger vehicles. Topics related to commercial vehicles, engines, and safety are covered by other SAE journals and thus are mostly excluded. The Journal rigorously peer reviews and disseminates authoritative, non-biased original research—theoretical and applied—and informative case studies with respect to the mechanical systems that comprise modern on-road automobiles.
Technical Paper

Intake O2 Concentration Estimation in a Turbocharged Diesel Engine through NOE

Diesel engines with their embedded control systems are becoming more and more complex as the emission regulations tighten, especially concerning NOx pollutants. The combustion and emission formation processes in diesel engines are closely correlated to the intake manifold O2 concentration. Consequently, the performance of the main engine controllers can be improved significantly, if a model-based or sensor-based estimation of the intake O2 concentration is available in the ECU. The paper addresses the modeling of the intake manifold O2 concentration in a turbocharged diesel engine. Dynamic models, compared to generally employed steady state maps, capture the dynamic effects occurring over transients. It is right in the transient that the major deviations from the stationary maps are found. The dynamic model will positively affect the control system making it more effective.
Technical Paper

Predictive Models of Intake Valve and Combustion Chamber Deposit Formation Tendency Based on Gasoline Fuel Composition

Internal engine deposits are predominantly the product of incomplete combustion of fuel and have the potential to negatively impact engine performance and exhaust emissions. The ability to expeditiously screen fuels for their deposit formation tendency would be advantageous. This paper presents Partial Least Squares (PLS) computational models with the ability to predict the degree of deposit formation tendency from the hydrocarbon composition of gasoline fuels. Furthermore, the relationship between gasoline fuel and Intake Valve Deposits (IVD) and Combustion Chamber Deposits (CCD) that form in Port Fuel Injected (PFI) engines is explored. The models utilize detailed hydrocarbon analysis (DHA) to resolve the complex mixture of hydrocarbons for different model fuels, which are correlated to ten years of engine data collected from a port fuel injected engine.
Technical Paper

Modelling and Numerical Simulation of the Noise Generated by Automotive Turbocharger Compressor

An effective technology to reduce emission and fuel-consumption is the use of turbochargers. A turbocharger increases the air pressure at the inlet manifold of the engine by using the waste energy from the exhaust gas to drive a turbine wheel that is linked to the compressor through a shaft. Besides the use in combustion engines, fuel cell systems for vehicle applications also need compressed air to achieve high power densities. Thereby, in fuel cell systems the noise emission of turbochargers is no longer masked by the combustion engine. In operation, the main noise sources are generated by the flow in the compressor and the different noise phenomena need to be understood in order to efficiently reduce the emitted noise and increase comfort. A huge potential in order to achieve this goal is a simulation based investigation to study in detail the flow mechanism, the aeroacoustic sources and its sound propagation.
Technical Paper

Sludge and Varnish Evaluation of Polyether Amine Gasoline Fuel Additives at “Complete Fuel System Cleaner” Aftermarket Fuel Additive Concentrations

Sludge and Varnish deposits that can build up in the crankcase originate in large part from fuel and fuel components that enter the crankcase through blow-by. These deposits can lead to a variety of engine issues including piston skirt deposits, cylinder bore scuffing, stuck lifters and oil filter plugging. A test has been developed to evaluate the contribution of “Complete Fuel System Cleaner” (CFSC) aftermarket fuel additives to crankcase sludge and varnish deposit formation. CFSC aftermarket fuel additives are typically formulated with polyether amine (PEA) chemistry and at concentrations that exceed 2000ppm. Three different commercially-available CFSC products were tested, containing two different classes of PEA chemistry - propylene oxide-based PEA (“PO-PEA”) and butylene oxide-based PEA (“BO-PEA”). Two of the three products contained the same PO-PEA chemistry, but at different concentrations, to show the effect of additive dosage.

Design of Racing and High Performance Engines

This book presents, in a clear and easy-to-understand manner, the basic principles involved in the design of high performance engines. Editor Joseph Harralson first compiled this collection of papers for an internal combustion engine design course he teaches at the California State University of Sacramento. Topics covered include: engine friction and output; design of high performance cylinder heads; multi-cylinder motorcycle racing engines; valve timing and how it effects performance; computer modeling of valve spring and valve train dynamics; correlation between valve size and engine operating speed; how flow bench testing is used to improve engine performance; and lean combustion. In addition, two papers of historical interest are included, detailing the design and development of the Ford D.O.H.C. competition engine and the coventry climax racing engine.