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Technical Paper

Wear Mechanisms of Methanol Fueled Engine

The wear mechanisms of the methanol engine were studied using dynamometer tests. Formic acid from methanol combustion mixes with the lubricant oil and attacks the metal surfaces. The iso tacho prorissis method was successfully applied to analyze the formic acid content of the used oil. A large amount of condensed water is also formed by methanol combustion and accelerates the wear. Wear can be effectively reduced by shortening lubricant oil change intervals, by using a special oil and by durable surface treatment of engine parts.
Journal Article

Water Injection Benefits in a 3-Cylinder Downsized SI-Engine

With progressing electrification of automotive powertrains and demands to meet increasingly stringent emission regulations, a combination of an electric motor and downsized turbocharged spark-ignited engine has been recognized as a viable solution. The SI engine must be optimized, and preferentially downsized, to reduce tailpipe CO2 and other emissions. However, drives to increase BMEP (Brake Mean Effective Pressure) and compression ratio/thermal efficiency increase propensities of knocking (auto-ignition of residual unburnt charge before the propagating flame reaches it) in downsized engines. Currently, knock is mitigated by retarding the ignition timing, but this has several limitations. Another option identified in the last decade (following trials of similar technology in aircraft combustion engines) is water injection, which suppresses knocking largely by reducing local in-cylinder mixture temperatures due to its latent heat of vaporization.
Technical Paper

Waste Heat Recovery of Passenger Car Using a Combination of Rankine Bottoming Cycle and Evaporative Engine Cooling System

Rankine bottoming system, which operates on waste heat of engine cooling, has been developped to improve the fuel economy of a passenger car. Evaporative engine cooling system is utilized to obtain high thermal efficiency and simplicity of the Rankine bottoming system. The bottoming system uses HCFC123 as a working fluid, and scroll expander as a power conversion unit. The results indicate that energy recovery, which depends on the ambient temperature, is almost 3 percent of engine output power at ambient temperature of 25°C.
Technical Paper

Visualization of EGR Influence on Diesel Combustion With Long Ignition Delay in a Heavy-duty Engine

The effects of EGR on diesel combustion were visually examined in a single-cylinder heavy duty research engine with a low compression ratio, low swirl, a CR fuel injection system and an eight-orifice nozzle. Optical access was primarily obtained through the cylinder head. The effects of EGR were found to be significant. NOx emissions were reduced from over 500 ppm at 0% EGR to 5 ppm at 55% EGR. At higher levels of EGR (approximately 35% or more) there was a loss in efficiency. Constant fuel masses were injected. Results from the optical measurements and global emission data were compared in order to obtain a better understanding of the spray behaviour and mixing process. Optical measurements provide fundamental insights by visualizing air motion and combustion behaviour. The NOx reductions observed might be explained by reductions in oxygen concentration associated with the increases in EGR.
Technical Paper

Vibration Analysis of Drive Line and Suspension Using Finite Element Models

Finite element aodels have been developed to analyze drive line and suspension vibration. For the analysis of booming noise, we have addressed the optimization of the differential gear carrier mounting system by using a virtual system and realization of it considering many constraints. To reduce the differential whine noise, a simulation method considering the transmitting error of the differential gear was applied. And we have approached for the subtle arrangements of many structural resonances with detail research of the drive line and suspension. For the reduction of road noise, we adopted the approach of shifting the node of the rear suspension member mode.
Technical Paper

Vehicle Dynamics Innovation with In-Wheel Motor

In-wheel motors (IWM) will be a key technology that contributes to the popularization of electric vehicles. Combining electric drive with IWM enables both good vehicle dynamics and a roomy interior. In addition, the responsiveness of IWM is also capable of raising dynamic control performance to an even higher level. IWM enable vertical body motion control as well as direct yaw control, electric skid control, and traction control. This means that IWM can replace most control actuators used in a vehicle chassis. The most important technology for IWM is to enable the motor to coexist with the brake and the suspension arms inside the wheel. The IWM drive unit described in this paper can be installed with a front double wishbone suspension, the most difficult configuration.
Technical Paper

Vehicle Behavior Under the Influence of Steering Dynamics by Means of Low Frequency Torque Input

This paper describes and confirms the effect of low frequency sinusoidal steering torque input on vehicle response and steering behavior using vehicle test, analysis with equations of motion and simulations. The vehicle response by low frequency torque input is quite different to the vehicle response by low frequency steer angle input. Steering system parameters such as moment of inertia, damping, friction and power steering assist torque have an effect on low frequency torque input steering system dynamics. The dynamic response of the vehicle with electric power steering (EPS) system, which has a big moment of inertia with electric motor and friction of the reduction gear, is affected by the steering system dynamic properties. The vehicle response by low frequency torque input test has capability for contribute to vehicle evaluation such as steer feel or maneuverability of handling.
Technical Paper

Validation Test Result Analysis of Plug-in Hybrid Vehicle

In recent years, many various energy sources have been investigated as replacements for traditional automotive fossil fuels to help reduce CO2 emissions, respond to instabilities in the supply of fossil fuels, and reduce emissions of air pollutants in urban areas. Toyota Motor Corporation considers the plug-in hybrid vehicle (PHV), which can efficiently use electricity supplied from infrastructure, to be the most practical current solution to these issues. For this reason, Toyota began sales of the Prius Plug-in Hybrid in 2012 in the U.S., Europe and Japan. This is the first PHV to be mass-produced by Toyota Motor Corporation. Prior to this, in December 2009, Toyota sold 650 PHVs through lease programs for validation testing in the U.S., Europe and Japan. Additional 30 PHVs were introduced in China in March 2011 for the same objective.
Technical Paper

Using Multi-Rate Filter Banks to Detect Internal Combustion Engine Knock

The wavelet transform is used in the analysis of the cylinder pressure trace and the ionic current trace of a knocking, single-cylinder, spark ignition engine. Using the wavelet transform offers a significant reduction of mathematical operations when compared with traditional filtering techniques based on the Fourier transform. It is shown that conventional knock analysis in terms of average energy in the time domain (AETD), corresponding to the signal's energy content, and maximum amplitude in the time domain (MATD), corresponding to the maximum amplitude of the bandpass filtered signal, can be applied to both the reconstructed filtered cylinder pressure and the wavelet coefficients. The use of the filter coefficients makes possible a significant additional reduction in calculation effort in comparison with filters based on the windowed Fourier transform.
Technical Paper

Two-Dimensional Temperature Measurements in Engine Combustion Using Phosphor Thermometry

A phosphor thermometry, for measurements of two-dimensional gas-phase temperature was examined in turbulent combustion in an engine. The reasonable temperature deviation and the agreement with calculated data within 5% precision were achieved by single-shot images in the ignition process of compression ignition engine. Focusing on the local flame kernel, the flame structure could be quantitatively given by the temperature. It became evident that the HCCI flame kernels had 1-3 mm diameter and the isolated island structures. Subsequently, the HTR zone consisted of the combined flame kernels near TDC.
Technical Paper

Turbulent Flame Speed Closure Model: Further Development and Implementation for 3-D Simulation of Combustion in SI Engine

A Turbulent Flame Speed Closure Model is modified and implemented into the FIRE code for use in 3D computations of combustion in an SI-engine. The modifications are done to account for mixture inhomogeneity, and mixture compression through the dependency of local equivalence ratio, pressure and temperature on the chemical time scale and a global reaction time scale. The model is also subjected to further evaluation against experimental data, covering different mixture and turbulence conditions. The combustion process in a 4-valve pentroof combustion chamber is simulated and heat release rates and spatial flame distribution are evaluated against experimental data. The computations show good agreement with the experiments. The model has proven to be a robust and time effective simulation tool with good predictive ability.
Technical Paper

Toyota's World First 8-Speed Automatic Transmission for Passenger Cars

TOYOTA has developed the world's first eight-speed automatic transmission (AA80E) for front-engine, rear-drive passenger cars. The AA80E developed for high-torque engines raises the level of power performance and fuel efficiency. To meet the size requirements needed for mounting in a passenger car application, an 8-speed geartrain, torque converter, transmission case and hydraulic control device were all newly-developed. Furthermore, the AA80E has benefited from technical developments to achieve an extremely high level of quietness and shifting performance. In this paper, the details of the AA80E are introduced.
Technical Paper

Toyota's U340E Four-speed Automatic Transaxle

TOYOTA has designed a new family of automatic transaxles named the “Super ECT”. These are the next generation of automatic transaxles (AT), for FWD passenger cars. The aim of this development was compactness, lightness, and improvements in fuel economy and shift quality. There are several kinds of transaxles included in this group to match each of the FWD passenger cars and engines. The “U340E,” a four-speed automatic transaxle, has been developed as one member of this family. This is one of the most compact and light AT in its class, and has greatly contributed to the fuel economy of vehicles. This paper will give an overview of the “Super ECT” and the major features and performance of the U340E.
Technical Paper

Toyota's New Six-Speed Automatic Transmission AB60E for RWD Vehicles

Toyota Motor Corporation has developed a new six-speed automatic transmission AB60E for longitudinal front engine rear wheel drive (RWD) vehicles. This transmission development was aimed at an improvement of power performance and fuel economy, while achieving a lightweight, compact package and a high torque capacity. In order to achieve this target, a high-capacity ultra-flat torque converter, a highly-rigid transmission case, and an ATF warmer with a valve to switch ATF circuits to an air-cooled ATF cooler have been newly developed. Moreover, a new transmission mode control logic “TOW / HAUL” has been developed to improve power performance and driveability during trailer towing. This automatic transmission has adopted the same gear train and hydraulic control system as the conventional six-speed automatic transmission A760E. This paper describes the structure, major features and performance of the transmission in detail.
Technical Paper

Toyota's New Six-Speed Automatic Transmission A761E for RWD Vehicles

Toyota Motor Corporation has recently developed a new six-speed automatic transmission (A761E) for Front Engine Rear Wheel Drive (FR) vehicles. Following the general trend of increased shift stages and a wider range of gear ratios, this six-speed automatic transmission has been developed with attention paid to the gear steps and a wider range of gear ratios. By balanced selection of close-ratio gears in a wider range, the change greatly improves the power performance and fuel economy of the vehicle. To further improve fuel economy we have adopted new technologies such as low-viscosity ATF, neutral control, and deceleration control by extending the fuel cut range (reset speed). We have also adopted a flat-shaped torque converter, small solenoids, an aluminum oil pump cover, etc. to realize the lightest six-speed automatic transmission in the world.
Technical Paper

Toyota's New Six-Speed Automatic Transaxle U660E for FWD Vehicles

Toyota Motor Corporation has developed a new six-speed automatic transaxle (U660E) for Front Wheel Drive (FWD) vehicles. Component parts of U660E are completely redesigned. By combining an innovative gear train which Toyota originally invented and newer technologies, U660E has achieved outstanding fuel economy, smooth and quick shift performance and quietness in a lightweight package among Automatic Transaxles (AT) with similar torque capacity.
Technical Paper

Toyota's New Integrated Drive Power Control System

Toyota has developed a new system, which uses integrated control of powertrain by PowerTrain Management (PTM), in order to improve driving comfort and reliability. This system is currently in use on Lexus's new LS460. This system is composed of 4 parts: a generation part, a mediating part, a modification part and a distribution part. In each part, processes are based on drive power and torque. In the generation part, requests from a programmed model driver, Driving Support Computer and Vehicle Dynamics Integrated Management (VDIM) are generated and expressed by drive power. In the mediating part, most suitable vehicle drive power was selected among the requests. In the modification part, the selected request is modified using a programmed powertrain model, which considers internal combustion engine condition and powertrain response and transmission's tolerance. In the distribution part, optimized engine torque and gear ratio are processed.
Technical Paper

Toyota's New Generation “Super ECT”(U140E) Four-Speed Automatic Transaxle

Toyota Motor Corporation has developed a new four-speed automatic transaxle U140E named “Super ECT”. The U140E has achieved compactness which enables it to mount on many new platforms, achieved high efficiency, which contributes to improve fuel economy, and it achieved good shift feeling, response, and reduce noise. This paper shows the major features and performance of the U140E.
Technical Paper

Toyota's New Five-Speed Automatic Transmission A750E/A750F for RWD Vehicles

Toyota Motor Corporation has developed a new five-speed automatic transmission (A750E/A750F) for longitudinal front engine rear wheel drive (RWD) vehicles. The development of this transmission has been aimed at improving fuel economy and power performance, achieving the world's top-level weight and compactness, while maintaining high torque capacity. In order to achieve this purpose, the gear train, torque converter, and other components are completely changed, and advanced technology has been applied. Moreover, this automatic transmission has achieved high-quality shift feel and quiet performance. This paper describes the major features and performance of this transmission in detail.
Technical Paper

Toyota's New Five-Speed Automatic Transaxle U150E for FWD Passenger Cars

A new five-speed automatic transaxle, U150E, has been developed for FWD passenger cars. The goals of the development of this transaxle are fuel economy improvement, better acceleration performance, and a smoother shift feel. U150E achieved its targets by adopting a wide gearing range and using hydraulic control system design based on various simulations. This paper describes the major features, performance of this automatic transaxle, and technical points of the development.