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With the development of the automobile industry, the requirements of quick response and high performance are put forward for the brake system. Since the traditional brake system cannot achieve these, the international brake parts manufacturers put forward an integrated electro-hydraulic brake system -the 1-Box. It can realize active brake through the servo motor. In addition, by controlling the pressure of the servo cylinder and working with solenoid valves, the wheel cylinder pressure can be controlled. However, it has some problems, such as hydraulic hysteresis disturbance and complex friction obstruction, which cause obstacles to the accurate control of wheel cylinder pressure. In this paper, the active braking pressure control strategy of wheel cylinders is designed based on 1-Box.

Rotary valve technology can provide increased flow area and higher discharge coefficients than conventional poppet valves for internal combustion engines. This increase in intake charging efficiency can improve the power density of four-stroke internal combustion engines, particularly at high engine speeds, where flow is choked through conventional poppet valves. In this work, the valvetrain of a light duty single cylinder spark ignition engine was replaced with a rotary valve train. The impact of this valvetrain conversion on performance and emissions was evaluated by comparing spark timing sweeps with lambda ranging from 0.8 to 1.1 at wide open throttle. The results indicated that the rotary valvetrain increased the amount of air trapped at intake valve closing and resulted in a significantly faster burn duration than the conventional valvetrain.

Emission legislation for passenger cars is requiring a drastic reduction of exhaust pollutants from internal combustion engines (ICE). In this framework, achieving a quick heating-up of the catalyst is of paramount importance to cut down the cold start emissions and meet future regulation requirements. This paper describes the development and the basic characteristics of a novel burner for gasoline engines exhaust systems designed for being activated immediately at engine cold start. The burner is comprised of a fuel injector, an air system, and an ignition device. The design of the combustion chamber is first presented, with a description of the air-fuel interactions and mixture formation processes. Swirl is used along with a flame-holder concept to anchor the flame at the mixer exit. Spray-swirl and spray-walls interaction are also discussed. Computational Fluid Dynamics (CFD) analyses have been used to investigate these aspects.

Modern automotive powertrains are operated using many control devices under a wide range of environmental conditions. The exhaust temperature must be controlled within a specific range to ensure low exhaust-gas emissions and engine-component protection. In this regard, physics-based exhaust-temperature prediction models are advantageous compared with the conventional exhaust-temperature map-based model developed using engine dyno testing results. This is because physics-based models can predict exhaust-temperature behavior in conditions not measured for calibration. However, increasing the computational load to illustrate all physical phenomena in the engine air path, including combustion in the cylinder, may not fully leverage the advantages of physical models for the performance of electric control units (ECUs).

Internal combustion engines are attached on the vehicle body using engine mounts composed of two cast iron brackets and a rubber isolator connecting them. Engine mount road load identification during vehicle durability tests on proving ground is a critical task for engine mount development. Using standard multi-axial load-cell is not possible unless major design revisions on the vehicle body or engine block are done. Using wheel force transducers and vehicle dynamic simulation tools need extensive model tuning work to get accurate load information. Hence, a custom multi-axial load-cell design is preferred for the engine mount load identification of a BCar I4 engine. The developed load-cell engine mount bracket can be installed without doing any design changes on the vehicle. Design, durability analysis, instrumentation, calibration and vehicle installation of custom designed six degree of freedom multi-axial load cell have been performed.

The demand for injection molded reinforced plastic products used in the automotive industry is growing due to the capability of the material for volume production, high strength to weight ratio, and its flexibility of geometry design. On the other hand, the application of fiber filled plastic composites has been challenging and subject of research during past decades due to the inability to accurately predict the mechanical strength and stiffness behavior owing to its anisotropic characteristics. This paper discusses a numerical simulation based technique using multiscale (2 scale Micro-Macro) modeling approach for short fiber reinforced plastic composites. Fiber orientation tensors and knit lines are predicted in microscale analysis using Autodesk Inc.’s Moldflow® software, and structural analysis is performed considering the homogenized structure in macroscale analysis using ANSYS® software tool.

1 Inside a paint booth to spray paint on vehicle bodies, bumpers, and other parts (hereinafter referred to as “works”), air whose temperature and humidity are controlled by air-conditioner is supplied by blower fans through filters. Dust-eliminated and regulated air flow is sent downward from top to bottom (hereinafter referred to as “downflow”) in the painting booth. Conventionally, paint which does not adhere to work in spraying (hereinafter referred to as “paint mist”) is collected while flowing at a high speed through a slit opening called venturi scrubber in a mixture of air and water. However, this mist collecting system using venturi scrubber requires a large space with a large amount of pressure loss while consuming substantial energy. By radically changing the mist collecting principle, we developed a new compact system with less pressure loss aiming to reduce energy consumption by 40% in a half-size booth.

Recent emissions standards have become more restrictive in terms of CO2 and NOx reduction. This has been translated into higher EGR rates at higher exhaust gas temperatures with lower coolant flow rates for much longer lifetimes. In consequence, thermal load for EGR coolers has been increasing and the interaction of boiling with thermal fatigue is now a critical issue during development. It is almost impossible to avoid localized boiling inside an EGR cooler and, in fact, it would not be strictly necessary when it is below the Critical Heat Flux (CHF). However when CHF is exceeded, film boiling occurs leading to the sudden drop of the heat transfer rate and metal temperature rise. In consequence, thermal stress increases even when film boiling is reached only in a small area inside the part. It is very difficult to accurately predict under which conditions CHF is reached and to establish the margins to avoid it.

An innovative control strategy, which is based on the Robust Model Predictive Control (MPC) methodology, was developed with the purpose of optimizing the engine thermal management; the proposed control strategy adjusts the coolant flow rate by means of an electric pump, in order to bring the cooling system to operate around the onset of nucleate boiling. In the present paper, the advantages of the proposed cooling approach are evaluated along the NEDC homologation cycle, which was both simulated and replicated by means of laboratory tests; the latter include coolant, lubricant and wall temperature measurements. Special attention was reserved to the warm-up period. The case considered herein is that of a Spark Ignition engine, about 1.2 dm3 displacement, and a comparison with standard crankshaft driven pump is included.

Engine mount is one of the temperature sensitive components in the vehicle under-hood. Due to increasing requirements for improved fuel economy, the under-hood thermal management has become very challenging in recent years. In order to study the effects of material thermal degradation on engine mount performance and durability; it is required to estimate the temperature of engine mount rubber during various driving conditions. The effect of temperature on physical properties of natural rubber can then be evaluated and the life of engine mount can be estimated. In this paper, a bench test is conducted where the engine mount is exposed to a step change in the environment around it, and the temperature of the rubber section is recorded at several points till a steady state temperature is reached. A time response curve is generated, from which a time constant is determined.

A heat pipe is a self-operating device which is capable of transferring large amounts of heat with a minimum temperature differences between the hot end (evaporator) and the cold end (condenser). However, a limited number of research work or analysis [1,2,3,4,5,6,7,8,9] has been reported in automotive industry on the applications of heat pipes in power train cooling. The advantage of a heat pipe heat exchanger is the possibility to use a more compact and lighter radiator. In addition, the proposed radiator is expected to be more robust as it is less sensitive to variations in ambient temperatures. In this paper, a proposed design for an automotive heat exchanger is investigated. The proposed design is evaluated through thermal simulation of heat pipes using various design parameters. The analysis addresses the ability of the heat exchanger to maintain engine coolant temperature at acceptable limits under different loading conditions.

The NASA Glenn Research Center has been developing a spacecraft open loop spray evaporative heat sink for use in pressure environments near sea-level, where evaporative cooling of water is not effective. The working fluid is R134a, a common refrigerant used in household appliances, considered safe and non-toxic for humans. The concept uses an open loop spray of R134a impinging on a heated flat plate, through which a closed loop of hot coolant flows, having acquired the heat from spacecraft electronics boxes, the cabin heat exchanger, and other heat sources. The latent heat of evaporation cools the outside of the hot plate, and through heat conduction, reduces the temperature of the coolant. The testing at NASA Glenn has used an electrically heated cylindrical copper target to simulate the hot plate. This paper will discuss the R134a feed system, the test matrix, and test results.

The kinematic flow ripple for gerotor pumps is often used as a metric for comparison among different gearsets. However, compressibility, internal leakages, and throttling effects have an impact on the performance of the pump and cause the real flow ripple to deviate from the kinematic flow ripple. To counter this phenomenon, the ports can be designed to account for fluid effects to reduce the outlet flow ripple, internal pressure peaks, and localized cavitation due to throttling while simultaneously improving the volumetric efficiency. The design of the ports is typically heuristic, but a more advanced approach can be to use a numerical fluid model for virtual prototyping. In this work, a multi-objective optimization by genetic algorithm using an experimentally validated, lumped parameter, fluid-dynamic model is used to design the port geometry.

The main drawback of an in-cylinder Low Pressure Direct Injection (LPDI) in a two-stroke engine is the difficulty of achieving a satisfactory vaporization level in low load conditions. The liquid droplets are characterized by large diameters and, when the temperature level and the velocity of the scavenging flow field are low, the time needed for the droplet vaporization and the homogenization with fresh air becomes too long to guarantee a suitable mixture formation. A transfer port injection allows a higher flexibility, due to the possibility of performing a mixed injection either directly in the cylinder or indirectly in the crank case, depending on the load request or engine speed. Also, an even lower injection pressure can be adopted with respect to an in-cylinder LPDI injection, which is relevant in case of lightweight and low power applications. On the other hand, the time available for the direct in-cylinder injection is limited to the scavenge phase.

Gasoline engines achieve maximum efficiency when operated at the knock limit. Knock control ignition systems enable an engine to operate in either continuous or intermittent light knock. Laboratory research has indicated it is harmless to run an engine within this range. Experience with knock control engines in passenger cars has shown erosion damage on pistons. Typical examples of knock erosion damage and ways of influencing severity of damage are discussed. Nickel coating has been developed as an effective and reliable technique to protect pistons from combustion knock erosion. Additional benefits of nickel coated pistons include: Reduced piston deposits Increased wear resistance in the top ring groove. Reduced cylinder head temperatures Engine text results and an analysis of engine efficiency increase due to nickel piston coatings is also presented.

A program to develop an aluminum tube stock alloy for vacuum-brazed heat exchangers with improved external corrosion resistance necessitated the use of accelerated laboratory corrosion tests to rank trial materials and ultimately qualify an alloy for production and sale. Brazed radiator sections and sheet samples were exposed to a variety of ASTM standard corrosion test environments. Metallographic examination of samples thus exposed demonstrated that the SWAAT test (ASTM G85:A3) closely replicated the air-side corrosion morphology found in aluminum radiators from the field. Samples exposed in test environments other than SWAAT did not generally exhibit the mixed intergranular/pitting morphology found in field retrievals. In neutral salt spray (ASTM B117), for instance, smooth-sided hemispherical pitting was the corrosion mode observed.

This study focuses on achieving a lower overall lap time at SAE Formula Student competition through a modification to the standard intake system. The lower lap time is achieved by widening the range of engine RPM which produces torque higher than 90% of the maximum value and lowering the engine RPM corresponding to the maximum torque. An intake system with ‘variable runner length’ is introduced to the 2015 racecar of KMUTT team. The values of intake lengths are determined from the wave equation with the goal of producing over 90% of the maximum torque of the baseline configuration over a range of engine RPM. Computer simulations are performed to determine the pressure at engine entry at various runner lengths. Finally, a prototype variable runner length intake system with linear motor actuators is constructed and installed on the racecar. Chassis dynamometer tests are performed to determine the engine torque for 3,000 – 10,500 RPM at all interested runner lengths.

A new model for corrective in-cylinder heat transfer has been developed which calculates heat transfer coefficients based on a description of the in-cylinder flow field. The combustion chamber volume is divided into three regions in which differential equations for angular momentum, turbulent kinetic energy and turbulent dissipation are solved. The resultant heat transfer coefficients are strongly spatially non-uniform, unlike those calculated from standard correlations, which assume spatial uniformity. When spatially averaged, the heat transfer coefficient is much more peaked near TDC of the compression stroke as compared to that predicted by standard correlations. This is due to the model's dependence on gas velocity and turbulence, both of which are amplified near TDC. The new model allows a more accurate calculation of the spatial distribution of the heat fluxes. This capability is essential for calculation of heat transfer and of component thermal loading and temperatures.

Existing methods for production ground testing the B-1B would create an undesirable and cumbersome work environment. The noise generated by the equipment along with hoses, cables and ducts on the floor produce a safety hazard. The information presented here deals with a new approach to meet the aircraft delivery rate requirement. Goals were established and a review of existing methods provided the “stepping stones” to the solution. The use of high technology computer applications is discussed along with the equipment types used on the B-1B bomber. This is the first automated approach to ground testing and checkout of complex aircraft mechanical systems.

Recent literature published by Toyota Motor Company[1] and Musashi Institute of Technology[2] have found that an offset crankshaft design has the potential for reducing friction and possibly increasing thermodynamic efficiency. In an effort to further evaluate this potential, a single-cylinder variant of a production GM 4.2L I6 engine was designed and tested. Cylinder pressure acquisition equipment and dynamometer torque measurements were used to quantify differences in combustion performance and firing friction between an offset crankshaft design and a standard baseline configuration. Extensive testing on the single-cylinder engine in both configurations found no significant frictional or thermodynamic differences to exist. Multiple tests of both design configurations were run in an effort to increase statistical confidence and test data showed good repeatability and precision.