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The IC engine still plays an important role in global markets, although electrified vehicles are highly demanded in some markets. Emission requirements for stoichiometric operation are challenging. This requires the bolted joints for turbo, EGR (Exhaust Gas Recirculation) and exhaust manifold to work under much higher temperature than before. How to avoid fastener breakage due to bolt bending caused by cyclic changes of the thermal conditions in engines is a big challenge. The temperatures of the components in the exhaust, EGR (Exhaust Gas Recirculation) and turbo systems change from ambient temperature to about 800 ~ 1000 °C when engines run at peak power with wide-open throttle. The temperature change induces catastrophic cyclic bending and axial strain to the fasteners. This research describes a method to reduce the cyclic bending displacement in the fasteners using a low friction washer.

Diamond-like carbon (DLC) films are of significant interest for the automobile field, because they possess the potential to improve friction properties under various sliding conditions. Among the various DLC films, the authors focus on silicon-containing DLC (DLC-Si) films, which exhibit extremely low friction coefficient under dry sliding conditions in an ambient air atmosphere. The aim of this study is to examine the influence of silicon content in DLC-Si films on the friction property of the films, and to clarify the low friction mechanism of the films. The friction test was conducted under dry sliding conditions. It was found that the films have an exceedingly low friction coefficient (about 0.05) ranging in silicon content from 4 at% to 17 at%. In order to examine the low friction mechanism of the films, surface analyses were done on the wear surface of DLC-Si films slid against bearing steel.

This paper describes that the effect of surface texture of sealing lip on lubrication and sealing performance examined experimentally on practical aspect. Hub seals of PAC type were used in this study. A test apparatus and operating procedure were shown. The seal which had texture on the lip had lower frictional torque than plain one. The effect of friction reduction with the textured surface preserved up to 15 cycles, which was equivalent to a travel distance of 30,000 km. The textured surface 10 μmRz with grease on the lip kept sealing performance up to -0.10 MPa in static and dynamic conditions. The endurance time of sealing of the textured surface was almost the same as that of the plain surface in seal endurance test with muddy water.

The new lubricant was newly developed for differential gear unit to contribute to all friction factors/conditions (Boundary, Hydrodynamic & those Mixed Lubrication) even if the differential gear is operating under very severe conditions such as high-gear-contact pressure and highly sliding speed. The main concept of development was selecting and formulating the optimized additives for severe lubrication conditions in order to achieve the best balance between thinner-film thickness and extreme pressure performance. In conclusion, by the application of both synthetic base oil instead of mineral one and activation technology of MoDTC in spite of ZnDTP free formulation, it is finally realized to reduce the torque of final drive unit by 40% and it can be estimated the 0.5% of CO2 reduction in actual vehicles.

This paper describes the development of new Si3N4 ceramics with both low friction coefficient and high strength, aiming at the reduction of friction force between cylinder liner and piston ring in low heat rejection engine. Si3N4 ceramics has high Young's modulus, therefore it provides lower coefficient of friction than iron. We thought that if adsorption ability of Si3N4 to lubricant oil were improved, coefficient of friction got still lower. In order to achieve this Fe3O4, which has superior adsorption ability, were used as one of additives for Si3N4. The obtained new Si3N4 had obviously lower coefficient of friction than conventional Si3N4 and it's strength were almost same as conventional Si3N4. Moreover, cylinder liner and piston ring were fabricated from developed Si3N4. They were tested using engine and reduction of friction force was confirmed.

The versatility of polyurethane RIM systems is shown to offer the capability of meeting the requirements of many new automotive applications. The effects of the isocyanate component composition on the physical properties of polyurethane RIM systems are reported. Results and interpretations are presented which give guidance to automotive design engineers in tailoring RIM material properties to match parts design and cost criteria. Several liquefied MDI products used in RIM systems are described and their influence on performance in automotive formulations is compared.

The New U.S. Evaporative Emission Regulations, which set forth the level of hydrocarbon evaporation generated from vehicles, have been applied in the industry since 1994. In order to meet the Regulations, the filler hose is required to be made for a one tenth of the gasoline permeability of that for conventional filler hose, without design change. The fuel filler hose must also provide a flexible configuration, such as a bellowed or a complicatedly curved shape In order to cope with the problems above, the Author, et al, have successfully developed A LOW PERMEATION FUEL FILLER HOSE which has a high freedom of configuration. During the first stage of development, the Author, et al, developed a hose of 2-layer structure using FKM rubber for inner layer as the permeation barrier, which is applicable in the bellow shape, by means of a unique molding technique.

Automotive Original Equipment Manufactures (OEM's) desire interior plastic components being used on consoles, doors, trim areas, and instrument panels to have very low gloss levels. In fact, some OEM's have specified a 2.0 or lower sixty degree Gardner gloss level for most first surface interior components molded in color (MIC) and without paint or a secondary finishing process such as a vinyl wrap. While a trend in the industry is to move toward PP based materials because PP parts are believed to provide lower gloss aesthetics and lower gloss gradients, key features and benefits of ABS products such as dimensional stability, impact, load bearing at elevated temperatures, and scratch resistance, are compromised. Recently, Dow Automotive has developed lower gloss capable ABS resins which also exhibit typical ABS physical and thermal properties.

This paper explains the reflectance characteristics of anodized aluminum and describes the finishing treatments which produce the desired low glow appearance required by The Proposed Federal Motor Vehicles Safety Standards. Certain of these low gloss producing treatments are easily incorporated into existing finishing lines and in many cases are more economical to apply than the present bright specular finish. The materials and processes used to satisfy this proposed standard are discussed fully.

A new generation of low heat capacitance Thermal Barrier Coatings (TBCs) has been developed under U.S. Dept. of Energy / Advanced Research Projects Agency - Energy (ARPA-E) sponsored research. The TBCs developed under this project have significantly lower thermal conductivity of < 0.35 W/m-K, thermal heat capacitance of < 500 kJ/m3-K, and density of <0.35 g/cm3. Two different binder types were used for thermal barrier coatings applied by High Velocity Low Pressure (HVLP) spraying to the piston, cylinder head, and valve combustion surfaces of a small natural gas engine. The effects of thermal barrier coatings on engine efficiency and knock characteristics were studied in a small, high compression ratio, spark-ignition, internal combustion engine operating on methane number fuels from 60 to 100. The new TBCs with low thermal conductivity and low thermal heat capacities have been shown to increase overall engine efficiency through reduced heat transfer to the piston and cylinder head.

A study is carried out here to examine the probable causes for the seemingly contradictory results found in the present-day literature on low-heat-rejection (LHR) engines, provide plausible explanations, and indicate possible directions for future research. Almost all numerical studies predict improved thermal efficiency, increased availability in the exhaust, and reduced in-cylinder heat rejection in the case of LHR engines. The degree of improvement varies considerably from a few percentage points to several, depending on the extent of insulation and whether or not turbocompounding and Rankine bottoming cycle are included. In these simulations, care is taken not to allow the volumetric efficiency to decrease due to higher cylinder temperatures in LHR engines. In addition, air-fuel ratio and, in many instances, peak conditions are maintained constant in both the LHR and conventionally-cooled engines.

In order to eliminate a cooling system from an internal combustion engine, we studied structures to reduce heat rejection from a combustion chamber. It was known to be very difficult to increase the heat-insulation rate of a low heat-rejection engine with a coated combustion chamber wall with a zirconia layer to more than 50%. Therefore a heat flux and temperatures were calculated by using the finite-element method in order to develop a new structure for a low heat rejection engine. The calculation results were compared with the temperatures measured in the engine which was fabricated with a silicon nitride combustion chamber wall incorporated in a heat-insulation structure composed of an air gap and a gasket of very low thermal conductivity. The result was that the compound heat-insulation structure was very effective in reducing heat rejection from the combustion chamber wall to the outer cylinder made of cast iron.

The paper gives a general overview of the state-of-the-art in low heat rejection (LHR) engines. It also gives experimental results obtained at SwRI with a single-cylinder research engine using an electrically heated cylinder liner to simulate LHR operation and examine the effects of increased liner temperature. It was concluded that the improvement in fuel economy from LHR operation is negligible in naturally-aspirated (NA) engines, about 7 percent in turbocharged (TC) engines and about 15 percent in turbocompound (TCO) engines. LHR operation reduces power in NA engines only. It increases NOx emissions by around 15 percent, but reduces HC and CO emissions. LHR operation offers benefits in the reduction of noise and smoke, and in operation on low cetane fuels. Much more research is needed to overcome the practical problems before LHR engines can be put into production.

This article investigates the effect of thermal barrier coating (TBC) on the cylinder components like piston crown top, cylinder liner, cylinder head inside and valves. The thermal barrier coated engines are otherwise known as low heat rejection (LHR) engines. Due to the insulation of the cylinder wall the heat transfer through the cylinder walls to the cooling system is reduced which change the combustion characteristics of the diesel engine. To know the changes during combustion the steady-state LHR engines operation have been studied by applying either the first or second law of thermodynamics. The state of the art of the thermal barrier coating is the plasma spray zirconia. In addition, other material systems have been investigated for the next generation of TBC. The study also focuses on coating method for Plasma Spray Zirconia (PSZ) to improve coating under high load and temperature cyclical conditions encountered in the real engine.

This paper presents a general overview about the previous research efforts into Low Heat Rejection Engine (LHRE) concept. The purpose of this paper is to explain the effect of insulation on engine performance, heat transfer characteristics, combustion and emission characteristics. Many researchers have carried out a large number of studies on LHRE concept. Some of them are experimental work and many are theoretical studies. In the case of LHR engines almost all theoretical studies predict improved performance but many experimental studies show different picture. This paper analyzes the reason for this deviation. The operating conditions, under which the experimental and simulation studies are carried out, have been clearly discussed. The factors, which affect thermal efficiency, combustion, and exhaust emissions in LHR engine, are deduced and their influences discussed. Effect of fuel injection characteristics on LHR engine performance is also reviewed.

A high output experimental single cylinder diesel engine that was fully coated and insulated with a ceramic slurry coated combustion chamber was tested at full load and full speed. The cylinder liner and cylinder head mere constructed of 410 Series stainless steel and the top half of the articulated piston and the cylinder head top deck plate were made of titanium. The cylinder liner, head plate and the piston crown were coated with ceramic slurry coating. An adiabaticity of 35 percent was predicted for the insulated engine. The top ring reversal area on the cylinder liner was oil cooled. In spite of the high boost pressure ratio of 4:1, the pressure charged air was not aftercooled. No deterioration in engine volumetric efficiency was noted. At full load (260 psi BMEP) and 2600 rpm, the coolant heat rejection rate of 12 btu/hp.min. was achieved. The original engine build had coolant heat rejection of 18.3 btu/hp-min and exhaust energy heat rejection of 42.3 btu/hp-min at full load.

This paper describes a new form of reciprocating engine and the work accomplished to date to investigate the capabilities and feasibility of this engine. This engine offers the substantial performance advantages that are thermodynamically possible when regeneration is applied to a low heat rejection (LHR) engine. Under a contract with the Naval Surface Warfare Center, a computer model that is capable of modeling the complex processes occurring in the LHR regenerated engine has been constructed. This model is being used to assess and examine the performance of various engine designs. In addition, design and materials issues associated with the most critical new component, the regenerator, are being investigated. Throughout this program, Caterpillar, Inc. has provided valuable technical support.

The dampers of semi-active vehicle suspensions have a limited working region. They are only capable of delivering control force in phase with damper contraction/expansion. Without special measures the delivered control force may be switched on and off abruptly at the entering/exiting of the damper working region. This causes deterioration of ride comfort quantified by the derivative of vehicle body acceleration (jerk). Proposed is a control algorithm modification for smooth force transition at the borders of the damper working region. A time based force modulation is used. A predictor of the time to exiting the working region is proposed to lower requested force in advance. A hybrid controller is investigated combining level and time based force modulation.

Safety-critical systems often lack scalability and exchangeability between OEMs and different suppliers. Although standards like AUTOSAR ease the development process, data exchanged on the network is subject to misinterpretation and programming faults during the development phase. Therefore this paper describes a way to abstract the needs of several communication networks used (e.g. Ethernet, FlexRay, CAN) from the software development process. Especially the integration of advanced driver assistance systems will enforce distribution of functional components and the exchange of sensor data necessary to track the status of the vehicle.