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Natural gas and hydrogen enriched natural gas has been tested as fuels together with diesel oil and RME in a single cylinder Scania research engine. The gas was introduced as port injection while the diesel was introduced as early direct injection. Because the gas was premixed with air before combustion and the diesel was injected early in the compression stroke, the engine ran close to HCCI mode. However, a more precise description of the combustion would be PPC (Partially Premixed Combustion) as the diesel oil was not expected to be totally premixed. The experiments revealed that the combustion phasing could successfully be controlled by the amount of diesel oil injected for loads between 3.5 and 7.5 bar IMEPg at 1200 rpm. For a given combustion phasing, the hydrogen was not found to influence the required amount of diesel noticeable. However, a large difference between the RME and diesel oil could be seen by the necessity to inject more RME to obtain the same combustion phasing.

A HCCI engine has been run at different operating boundaries conditions with fuels of different RON and MON and different chemistries. The fuels include gasoline, PRF and the mixture of PRF and ethanol. Six operating boundaries conditions are considered, including different intake temperature (Tin), intake pressure (Pin) and engine speed. The experimental results show that, fuel chemistries have different effect on the combustion process at different operating conditions. It is found that CA50 (crank angle at 50% completion of heat release) shows no correlation with either RON or MON at some operating boundaries conditions, but correlates well with the Octane Index (OI) at all conditions. The higher the OI, the more the resistance to auto-ignition and the later is the heat release in the HCCI engine. The operating range is also correlation with the OI. The higher the OI, the higher IMEP can reach.

A multi-zone model was used to predict the operating range of homogeneous charge compression ignition (HCCI) engine, the boundaries of the operating range were determined by knock (presented by ringing intensity), partial burn (presented by combustion efficiency) and cycle-to-cycle variations (presented by the sensitivity of indicated mean effective pressure to the initial temperature). A HCCI engine fueled with iso-octane was simulated, and it was found that the knock and cycle-to-cycle variations predicted by this model showed a satisfactory agreement with measurements under different initial temperatures and equivalence ratios, and the operating range was well reproduced by the model. Furthermore, the model was applied to develop the operating range for different engine speeds by changing initial temperature and equivalence ratio. Finally, the potential to expand the operating range of HCCI engines through two strategies, i.e. variable compression ratio and boost, were investigated.

This paper examines the successful use of HCCI combustion in a standard issue model-aero “diesel” engine. This two-stroke engine, unlike the more common glow-plug versions, operates without any form of combustion initiator. The fuel and air are premixed using a simple carburettor and ignited by piston compression only. The engine therefore operates in HCCI mode even though it is referred to as a “model diesel engine”. Of particular interest is the fact that the engine is easily started from cold, warm and hot conditions. It runs stably from idle to over 11000rpm and is shown to run at high load points across the speed range with extremely conservative pressure rise rates. Furthermore, this engine is shown not to exhibit any knocking (high pressure oscillations) within its normal range of operation. The speed-load operational envelope of the engine is mapped out using a range of propellers and a propeller speed-load calibration rig.

The local temperature of the in-cylinder mixture before combustion is critical to enable auto-ignition (AI) in a gasoline engine. Spark assistance is one of the methods to ensure the critical temperature required for auto-ignition. The application of the spark gives a time controlled initiation to the onset of ignition. In the work reported in this paper, spark assisted AI was experimentally investigated on a small two-stroke engine. The spark assistance and internal exhaust gas recirculation (EGR) were jointly applied to achieve and control AI. The results showed that at higher engine load, the onset timing of AI had a clear dependence on the timing of the spark and was consistent from cycle to cycle. At lower engine load, the assistance of the spark became necessary for keeping the AI operation to continue.

Strict NOx and soot emission regulations for Diesel engines have created an interest in low-temperature partially-homogeneous combustion regimes in both the US and Europe. One strategy, Homogeneous-Charge Late-Injection (HCLI) combustion utilizes 55% or more cooled external Exhaust Gas Recirculation (EGR) with a single Direct Injection strategy to control ignition timing. These engines are operated at low temperatures to ensure near zero NOx emissions, implying that fuel in the thermal boundary layers will not reach sufficient temperature to fully oxidize, resulting in Unburnt Hydrocarbon (UHC) and CO emissions. Of particular interest to HCLI engines are the UHC's that are not fully oxidized by the Diesel Oxidation Catalyst (DOC). Experimental measurements reveal that at average equivalence ratios greater than 0.8, methane is the single largest tailpipe-out UHC emission.

It has been known from multi-zone simulations that HCCI combustion can be significantly affected by temperature stratification of the in-cylinder gas. With the same combustion timing (i.e. crank angles at 50% heat release, denoted as CA50), large temperature stratification tends to prolong the combustion duration and lower down the in-cylinder pressure-rise-rate. With low pressure-rise-rate HCCI engines can be operated at high load, therefore it is of practical importance to look into more details about how temperature stratification affects the auto-ignition process. It has been realized that multi-zone simulations can not account for the effects of spatial structures of the stratified temperature field, i.e. how the size of the hot and cold spots in the temperature field could affect the auto-ignition process. This question is investigated in the present work by large eddy simulation (LES) method which is capable of resolving the in-cylinder turbulence field in space and time.

The incomplete combustion and misfire of diesel engine during starting result in unwanted white smoke. The histories of combustion and emission in different phases under different start conditions were studied in this paper. The optimization of the fuel injection control strategy under start conditions was performed. When the diesel engine is started under low temperature, the control strategy adapted to start the engine with a certain constant fuel mass injected per cycle, there may be misfire cycles in the initial period or in the transitional process, which is mainly caused by the mismatch between the fuel mass injected per cycle and the instantaneous engine speed. Therefore, an optimized control strategy was put forward, namely, the engine starts with high fuel mass injection in the first several cycles and then decreases step by step during the transitional period until it operates at idle condition. This strategy was validated to decrease significantly the misfire cycles.

Race internal combustion engines are the result of several years of design made to satisfy the growing demand of high specific power. As a result of this increased specific power demand all of the engine components that require lubrication are exposed to a broader range of more extreme operating conditions. Hence an optimized design of a race engine lubricant circuit is becoming much more important, due to the necessity to have its effectiveness with a rational management of its own energy. In this paper, Authors analyse a motorbike high performance lubrication circuit by a simulation methodology, already used and validated for other high performance engine types. It will be illustrated a simulation model, made by mono-dimensional (1D) code, which allows to study all lubricant circuit behaviour, analyzing parameters that are not easy to evaluate experimentally and that, too often, designers don't take into account during engine development.

An in-vehicle FTIR emission measurement system was used to investigate the exhaust emissions under different real world urban driving conditions. Five different driving cycles were developed based on real world urban driving conditions including urban free flow driving, junction maneuver, congested traffic and moderate speed cruising. The test vehicle was a EURO 2 emission compliant SI car equipped with temperature measurement along the exhaust pipe across the catalyst and real time fuel consumption measurement system. Both regulated and non-regulated emissions were measured and analyzed for different driving cycles. All journeys were started from cold. The engine warm up features and emissions as a function of engine warm up for different driving conditions were investigated.

A short study has been conducted to measure both AFR and residual gas fraction on a cycle-by-cycle basis for a gasoline engine during cold start and during a throttle transient. In-cylinder and exhaust port measurements were recorded using a fast response NDIR instrument to provide some insight in to the dynamic processes involved during these important transient engine conditions. The CO&CO2 results are presented showing evidence of the large cyclic variability of fuel delivery during the first few firing cycles of the start. Misfires are also identified. A description of a post-processing tool is discussed for conversion of this data to AFR. It is hoped that this measurement method will be valuable to engine researchers and calibrators as a tool to understanding and lowering cold start and throttle transient HC and CO emissions as well as validating internal EGR models.

The effectiveness of after-treatment systems depends on the exhaust gas temperature, which is low during cold-start. As a result, Euro III, Euro IV and FTP75 require that the emissions tests include exhaust from the beginning of cold start. It is proved that 50%∼80% of HC and CO emissions are emitted during the cold start and the amount of unburned fuel from the crevices during starting is much higher than that under warmed engine conditions. The piston crevices is the most part of combustion chamber crevices, and results of mathematical simulations show that the piston crevice contribution to HC emissions is expected to increase during cold engine operation. Based on the transient HC test data and the double zone combustion model, this paper presents the study of the crevice HC Mechanism of the first firing cycle at cold start on an LPG SI Engine. A fast-response flame ionization detector (FFID) was employed to measure transient HC emissions of the first firing cycle.

All automotive fleets' ownerships want to increase their fleets' availability; therefore, they resort to consider the conventional maintenance policy. Despite of, this policy increases fleets availability but the cost will be high. This is due to replace the parts before the end of their lifetime. On the other hand, this policy is based on time where it is not cost-effective. Consequently, this conventional maintenance policy is not adequate to fulfill the needs of high availability for automotive fleets. However, in this paper the study is directed to condition-based predictive maintenance concept as an alternative policy to determine fleet's health for increasing the fleet availability and to reduce the operating cost. The concept is based on predicting the system degradation and calculating the reliability function for the component. An application carried out on internal combustion engine crankshaft main bearing to illustrate the effectiveness of this technique.

A 3D-CFD model with detailed chemical kinetics was developed to investigate the combustion characteristics of HCCI engines, especially those fueled with hydrogen and n-heptane. The effects of changes in some of the key important variables that included compression ratio and chamber surface temperature on the combustion processes were investigated. Particular attention was given, while using a finer 3-D mesh, to the development of combustion within the chamber crevices between the piston top-land and cylinder wall. It is shown that changes in the combustion chamber wall surface temperature values influence greatly the autoignition timing and location of its first occurrence within the chamber. With high chamber wall temperatures, autoignition takes place first at regions near the cylinder wall while with low surface temperatures; autoignition takes place closer to the central region of the mixture charge.

“Anti-scratch performance” is the highest in customer's needs of paint. To achieve anti-acid and anti-scratch performance, we selected 2K-urethane because of a high degree of freedom in paint design. In addition, we have done a precise molecular design of the acrylic polyol and the isocyanate. As a result, “a highly durable, soft, fine-crosslinking paint film” was achieved, and “anti-scratch clear coat” that surpassed the current clear coats was developed.

Chrome plated automotive exterior parts continue to be popular. A good understanding of the properties of the unplated and plated parts is required to have the lowest cost successful design. In this work, traditional mechanical properties are compared between plated and unplated ABS and ABS+PC grades of plastic. Additional findings are shared for the thermal growth properties that are important to the designer who is trying to minimize gaps to adjacent components and for the engineer who wants the plated parts to resist cracking or peeling. Finally, some bend testing results are reviewed to understand better the susceptibility of the chrome plated plastics to crack when bent. In total, these results will help the exterior trim part designers optimize for cost, fit and finish.

Decorative chromium electroplating from an electrolyte based on chromium trioxide has been successfully used for many years. The deposit satisfies many demands including aesthetics, durability and economy. However, chromium trioxide is classified as carcinogenic and PFOS (which is used as a mist suppressant in these processes) has been shown to be bio accumulative. A PFOS free system based on trivalent chromium sulphate salts is proposed which avoids these issues and is capable of meeting recognised high performance standards. Production experience proves that this new system is able to satisfy even the most demanding automotive chromium plating applications. This paper will identify the issues driving platers to consider alternative technology, outline why supply chain partners need to be aware of these issues and explain why this new trivalent chromium technology is now a viable alternative to traditional hexavalent chrome plating processes.

Heavy trucks are becoming more common in use for international transportations, with longer highways and long driving hours contributing corresponding increases in driver's fatigue that is related to accidents. In this paper a detailed procedure is proposed to improve a highway truck seat. A dynamic model of an on-highway truck seat is simulated using Simulink toolbox in MATLAB. The seat suspension including the cushion is mounted on the cab floor of a half truck model and excited by a rapid excitation of step input. The seat suspension system controller is designed to improve the ride quality of the driver. Genetic Algorithms (GA) is used to obtain the coefficients of the control parameters. In addition, model outputs comparison of the proposed design to a conventional passive seat suspension using the maximum overshoot and the root mean square (RMS) values of both, the driver acceleration and the seat suspension working space.

In order to advance vehicle stability control strategies and provide enhanced customer benefits, a methodology for combining the capabilities of an active driveline system capable of direct yaw control with a vehicle stability assist controller (also referred to as ESC, electronic stability control) has been developed. As a basis, the traditional ESC operation of using only brake and throttle control is compared and contrasted against customer needs and expectations. Using the existing ESC stability control system as a representative yaw stability control algorithm, the actuation capabilities of a controllable AWD system are arranged through a simple CAN communication scheme to serve as an available extension to the ESC actuator set (i.e. brake, throttle and now AWD direct yaw moment control). The ESC unit is allowed to request a rear axle torque amount change to the controllable AWD unit ECU.

Lane keeping assistant system (LKAS) is expected to reduce the driver workload with assisting the driver during driving and is regarded as a promising active safety system. For the proposed LKAS which requires cooperative driving between driver and the assistance system, a Model Based Predictive Controller (MBPC) is proposed to minimize the effect of system overshoot caused by the time delay from the vision-based lane detection system. In order to validate the proposed LKAS controller, a HIL (Hardware In the Loop) simulator is built using steering mechanism, single camera, torque motor, sensors, etc. The performance of the proposed system is demonstrated in various roadways.