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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.

Advanced Driver Assistance System (ADAS) in combination with other active safety features like air bags etc. is gaining popularity. Vision based ADAS systems perform well under ideal lighting, illumination and environmental conditions. However, with change in illumination and other lighting related factors, the effectiveness of vision based ADAS systems tend to deteriorate. Under conditions of low light, it is therefore important to develop techniques that would offset the effects of low illumination and generate an image that appears as if it were taken under ideal lighting conditions. To accomplish this, we have developed a method, that uses local color statistics from the host image with low illumination, and enhance the same using an adaptive color transfer mechanism. By taking cues from the properties of ideal images that are saved in a database, the proposed method tends to recreate the input scene (with low illumination), into a near ideal scene, based on the database images.

Major advances in TWC catalysis have been reported in the past several years. Possibly the most significant of these has been the development of high loaded Pd-only catalysts which demonstrate improved HC and light-off performance. Such systems have demonstrated the ability to meet California Low Emission Vehicle Standards without the need for electrically heated catalysts or hydrocarbon trap technology. The integration of improved low temperature catalyst performance with optimized catalyst substrate properties and vehicle calibration can result in further emission reductions. This paper describes the development of a low temperature Pt/Pd catalyst technology which offers light-off advantages over Pd-only catalysts.

Gasoline compression ignition (GCI) is widely studied for the benefits of simultaneous reduction in nitrogen oxide (NOX) and soot emissions without compromising the engine efficiency. Despite this advantage, the operational range for GCI is not widely expanded, as the auto-ignition of fuel at low load condition is difficult. The present study aims to extend the low load operational limit for GCI using negative valve overlap (NVO) strategy. The engine used for the current experimentation is a single cylinder diesel engine that runs at an idle speed of 800 rpm with a compression ratio of 17.3. The engine is operated at homogeneous charge compression ignition (HCCI) and partially premixed combustion (PPC) combustion modes with the corresponding start of injection (SOI) at −180 CAD (aTDC) and −30 CAD (aTDC), respectively.

Self-lubricating composite bearings have been developed which have proven effective in reducing maintenance of off-highway equipment. The bearings rely on the strength of fiber glass/epoxy composite, the abrasion resistance of Nomex, and the lubricating qualities of Teflon to provide high load capacity and long service life. Wear rates, load capacities and applications are discussed.

The growing need for clean air has prompted automobile manufacturers to invest large amount of time and money to control the emission from the automobile. The use of catalytic converter is one of the popular methods to control the emission from the vehicle. The catalytic converters are active only after reaching the ‘light off’ temperature which is fairly high and it takes two to three minutes for the catalyst attain the light off temperature from cold start. During this period, the exhaust gases enter into the atmosphere untreated. Low Mass Electrically Heated Metal Catalyst (LMEHMC) is very effective in reducing such emissions during this period as the Electrically Heated Catalyst (EHC) reaches the required light off temperature quickly. In the present investigation, an attempt has been made to control the cold-start emission of a multi-cylinder SI engine using LMEHMC with EHC filled with copper oxide as catalyst of different volumes.

According to authors' previous research, high pressure hydrogen engines with direct injection right before TDC and spark ignition obtain high performance and eliminate almost. abnormal combustion. This study has clarified the mooted points in the flame propagation to adjacent jets and the control of the optimum spark timing and large NOx emissions even in leaner than excess air ratio of λ=2. Nitric oxides (NOx) is the only the pollutant in the exhaust gases emitted by hydrogen engines. It has been found that the NOx formation largely depends on the mixture formation method. In order to operate the engine in a small amount of NOx, an experimental study was carried out to investigate the reduction of NOx and the output power by using dual mixture formation method, external mixture formation and direct injection.

Engine and aftertreatment solutions have been identified to meet the upcoming ultra-low NOX regulations on heavy duty vehicles in the United States and Europe. These standards will require changes to current conventional aftertreatment systems for dealing with low exhaust temperature scenarios while increasing the useful life of the engine and aftertreatment system. Previous studies have shown feasibility of meeting the US EPA and California Air Resource Board (CARB) requirements. This work includes a 15L diesel engine equipped with cylinder deactivation (CDA) and an aftertreatment system that was fully DAAAC aged to 800,000 miles. The aftertreatment system includes an e-heater (electric heater), light-off Selective Catalytic Reduction (LO-SCR) followed by a primary aftertreatment system containing a DPF and SCR.

A wide range of air/fuel ratios and exhaust gas recycle rates were examined in an automotive test engine for the purpose of reducing NOx emissions to low levels. A minimum NOx level of 0.4 g/mile on the 1972 Federal Test Procedure was obtained at a rich A/F of 12 and a recycle rate of 25%. With this combination, the fuel consumption increased approximately 15% and the wide open throttle (WOT) power decreased about 30%. Combustion in the cylinders was good and the vehicle operated smoothly. Comparable results were not obtained with lean mixtures. The results of this study do not establish the feasibility of meeting the 1976 NOx standard with the rich mixture, high recycle technique. Further, the increased CO and HC emissions would have to be controlled by exhaust gas treatment.

Careful study has been made of the aspects of unstable combustion due to heavy E.G.R. (Exhaust Gas Recirculation) while attempting to achieve low NOx emission levels. The authors have concluded that the fast burn engine allowed a wider E.G.R. tolerance, with stable combustion, at very low NOx emission levels in comparison with the conventional SI engine. This was true even under heavy E.G.R. Better fuel economy was achieved through a combination of improved cycle efficiency (using the fast burn concept) and reduced pumping loss (applying heavy E.G.R.). The Nissan NAPS-Z Fast Burn Engine was developed as a consequence of and through the use of the results mentioned above. The characteristic data of the engine (4 cyl. 1.8 ltr.) described in the paper showed a method of achieving a low NOx emission level with better fuel economy and driveability.

Recently, the noise regulations are being reinforced to restrict the noise levels in the workplace and to protect the operator on the construction equipment. So, the cabin noise level is one of the crucial barometers determining the quality of construction equipment. In this paper, numerical and experimental studies for the identification of noise sources and noise transmission paths were carried out for the cabin noise control of construction equipment. First of all, measurements of sound absorption, transmission and radiation noise were performed using cabin assembly models. Noise contribution factors of cabin components were obtained through these measurements. Using these results, cabin noise levels were re-analyzed. The calculated noise levels for cabin model were confirmed to agree well with measurement results within 3dB [1]. Furthermore, acoustic resonance can be avoided at the design stage to control the booming noise.

The paper divides into two parts. First the investigation of the noise of an unconventional design of two cycle diesel engine, including the results of applying known noise reducing features to it. Then taking one component of that engine, the scavenge blower, and re-designing it from first principles to produce a low noise machine suitable for the low noise engine. The final assembly of engine and blower demonstrated that the noise that has been regarded the characteristic of the two cycle engine is in fact that of the Roots type blower and when eliminated the noise level can be quite low. The present test bed noise level of 97/98 dBA at 1 metre shows promise of this type of engine meeting the legislative requirements of the 1980's.

Investigations have been carried out as to whether cooling systems with tangential flow fans can be designed with the same noise, efficiency and package size as acoustically optimized cooling systems using axial flow fans. Previous work had shown that cooling systems with commercially available tangential flow fans could not meet these requirements. In the case of low and wide radiator cores, however, the application of tangential flow fans appeared advantageous since the tangential flow fan is fully adaptable to the width of the radiator core. For the main part of the development work an experimental tangential flow fan was used which permitted a wide range of modifications to be made and enabled the air flow to be observed. Extensive development resulted in a compact cooling system with a radiator core located downstream close to the impeller and with characteristics coming up to expectations.

Molded automotive headliners are composed of a matrix of glass fibers and an organic thermosetting binder. Conventional fiberglass binders for applications such as automotive headliners contain nitrogen based formaldehyde scavenging compounds to reduce the release of highly irritating formaldehyde fumes in the product forming and molding steps. The scavenging compounds employed can result in the formation and deposition of objectionable amine compounds, specifically trimethylamine, in the finished products. Since the release of highly odorous compounds in a vehicle interior is very undesirable, a new fiberglass binder has been developed for molded products that eliminates the root cause of objectionable odors.