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The legibility and usefulness of liquid crystal displays (LCD’s) in automotive applications depends entirely on the type and control of the illumination technique chosen. The use of a fluorescent indicator panel (FIP) as an illumination source from the backside of an LCD is proposed. The LCD surface brightness levels and legibility over a wide ambient lighting range are discussed. Three operational modes (transmissive, reflective, and transflective) of the FIP-LCD system are considered.

Today, millions of liquid crystal displays are used in wrist watches, clocks, pocket calculators, and measuring instruments. For automotive application, many problems had to be solved. The present paper gives a survey of the most important results of VDO development work aiming at a display system which will be fully suited for automotive application.

Liquid crystal technology has been advanced to the stage that it is possible for it to be incorporated into glazing material. The use of liquid crystals allows visible light passing through glass to be “switched” from specular to diffuse with the application of an electrical field. This technology provides new design opportunities for glazing material in both architectural and transportation markets.

An optical access engine was used to image the liquid film evaporation off the piston of a simulated direct injected gasoline engine. A directional injector probe was used to inject liquid fuel (gasoline, i-octane and n-pentane) directly onto the piston of an engine primarily fueled on propane. The engine was run at idle conditions (750 RPM and closed throttle) and at the Ford World Wide Mapping Point (1500 RPM and 262 kPa BMEP). Mie scattering images show the liquid exiting the injector probe as a stream and directly impacting the piston top. Schlieren imaging was used to show the fuel vaporizing off the piston top late in the expansion stroke and during the exhaust stroke. Previous emissions tests showed that the presence of liquid fuel on in-cylinder surfaces increases engine-out hydrocarbon emissions.

The effects are described in aluminum brazing of a phenomenon known as Liquid Film Migration (LFM). This is primarily encountered when -O temper parts are formed and subsequently brazed. If the combination of material homogenization, alloy and cold work is such that the material does not recrystallize totally before the brazing temperature is reached, then the system begins to equilibrate by rapid solid state diffusional processes. These create a moving liquid interface which sweeps from the clad/core interface into the core of the material. This causes significant compositional changes in the volume through which the liquid film passes. Reduced brazeability (filler metal flow) results from the rapid diffusion of silicon into the core. Additionally, a coarse band of intermetallics is formed upon solidification of the enriched liquid zone which can impair corrosion resistance.

The objective of this project is to establish the feasibility of measuring the thickness of a thin dynamic liquid film using internally reflected light. The principle of the sensor operation is demonstrated through static calibration curves. The influence of various liquids is also explored by testing water, motor oil, Stoddard fluid, and finally skim milk to show the effect of a semi-opaque liquid. The response of the system to 1.25 millisecond impulse of light caused by a 500 Hz square wave is examined to demonstrate the dynamic range of the device. A wave machine is used to demonstrate the dynamic response of the sensor. These measurements are made with the early version of the film thickness sensor.

The effect of the presence of liquid fuel in the intake manifold on unburned hydrocarbon (HC) emissions of a spark-ignited, carbureted, air-cooled V-twin engine was studied. To isolate liquid fuel effects due to the poor atomization and vaporization of the fuel when using a carburetor, a specially conditioned homogeneous, pre-vaporized mixture system was developed. The homogeneous mixture system (HMS) consisted of an air assisted fuel injection system located approximately 1 meter upstream of the intake valves. The results from carburetor and HMS are compared. To verify the existence of liquid fuel in the manifold, and to obtain an estimate of its mass, a carburetor-mounted liquid fuel injection (CMLFI) system was also implemented. The conditions tested were 10% and 25% load at 1750 RPM, and 25%, 50%, and 100% at 3060 RPM. The results of the comparison show that the liquid fuel in the intake manifold does not have a statistically significant influence on the averaged HC emissions.

Liquid fuel flow into the cylinder an important source of hydrocarbon (HC) emissions of an SI engine. This is an especially important HC source during engine warm up. This paper examines the phenomena that determine the inflow of liquid fuel through the intake valve during a simulated start-up procedure. A Phase Doppler Particle Analyzer (PDPA) was used to measure the size and velocity of liquid fuel droplets in the vicinity of the intake valve in a firing transparent flow-visualization engine. These characteristics were measured as a function of engine running time and crank angle position during four stroke cycle. Droplet characteristics were measured at 7 angular positions in 5 planes around the circumference of the intake valve for both open and closed-valve injection. Additionally the cone shaped geometry of the entering liquid fuel spray was visualized using a Planar Laser Induced Fluorescence (PLIF) setup on the same engine.

The behavior of the liquid fuel impinging on the piston top of a direct-injected, spark-ignited (DISI) engine operating under stratified conditions is investigated using floodlight laser-induced fluorescence (LIF). The combustion chamber geometry offers wall-guided stratification using a high-pressure injector impinging on an inclined piston bowl. The LIF signal is collected through the bottom of the quartz piston, allowing observation of the footprint of the spray during and after spray development. Nitrogen gas is used to replace air in order to minimize oxygen quenching and increase the signal. The results show that at typical piston top temperatures expected in warmed-up operation (150-180 °C), a liquid film and ring around the area where the fuel jet impinges is present through the time of spark (20° before top center). The presence of the fuel film is not very sensitive to the surface temperature.

The occurrence of liquid fuel in the cylinder of automotive internal combustion engines is believed to be an important source of exhaust hydrocarbon (HC) emissions, especially during the warm-up process following an engine start up. In this study a Phase Doppler Particle Analyzer (PDPA) has been used in a transparent flow visualization combustion engine in order to investigate the phenomena which govern the transport of liquid fuel into the cylinder during a simulated engine start up process. Using indolene fuel, the engine was started up from room temperature and run for 90 sec on each start up simulation. The size and velocity of the liquid fuel droplets entering the cylinder were measured as a function of time and crank angle position during these start up processes. The square-piston transparent engine used gave full optical access to the cylinder head region, so that these droplet characteristics could be measured in the immediate vicinity of the intake valve.

The purpose of this paper is to describe a novel liquid fuel conditioning process incorporated within a 2-stroke internal combustion engine. The process takes place inside a small vaporization chamber integrated within the engine piston. The vaporization chamber inlet/outlet is located on the piston skirt. After an injected liquid fuel has evaporated and superheated inside the vaporization chamber, it is transferred into the cylinder to form a homogenous mixture with a fresh air charge. Combustion is triggered by compression-ignition of a pilot fuel spray. After combustion completion, hot combustion products enter the vaporization chamber via a transfer port formed in the cylinder wall. Thereafter, those products are entrapped inside the vaporization chamber with the inlet/outlet aperture sealed by the cylinder wall for a portion of the cycle.

The purpose of this paper is to describe a novel liquid fuel conditioning process that is incorporated within a Wankel type rotary engine. The process takes place inside three small vaporization chambers attached to the engine rotor. After an injected liquid fuel has evaporated and superheated inside a vaporization chamber, it is transferred via a transfer port into a moving chamber near the middle of a compression phase to form a stratified mixture with a prevailing fresh air charge. Combustion is triggered by a spark. Near the end of an expansion phase hot combustion products enter the vaporization chamber via an entrapment port. Thereafter, those products are entrapped inside the vaporization chamber during about 180° of rotor rotation. Unlike spark ignition, compression ignition or homogeneous charge compression ignition engines, here the liquid fuel is injected into the vaporization chamber during the exhaust phase of a preceding cycle.

The presence of liquid fuel inside the engine cylinder is believed to be a strong contributor to the high levels of hydrocarbon emissions from spark ignition (SI) engines during the warm-up period. Quantifying and determining the fate of the liquid fuel that enters the cylinder is the first step in understanding the process of emissions formation. This work uses planar laser induced fluorescence (PLIF) to visualize the liquid fuel present in the cylinder. The fluorescing compounds in indolene, and mixtures of iso-octane with dopants of different boiling points (acetone and 3-pentanone) were used to trace the behavior of different volatility components. Images were taken of three different planes through the engine intersecting the intake valve region. A closed valve fuel injection strategy was used, as this is the strategy most commonly used in practice. Background subtraction and masking were both performed to reduce the effect of any spurious fluorescence.

This paper considers the practical feasibilty of an overall vehicle power system and the likelihood of developing a fuel-cell electric car at an acceptable price in the next decade. High-temperature fuel cells are discounted because of long start-up time and the weight of the individual units. The most feasible direct-fueled fuel battery is the methanol/air and hydrazine/air systems. The advantages of this type fuel cell are simplicity, instantaneous start-up capability, instantaneous availability of reactants, and a simple control for maintaining the proper concentration of fuel. Methanol is the preferred soluble fuel since it is relatively inexpensive; whereas hydrazine is toxic and mildly corrosive. The fuel cell will be acceptable only when it is economically justified in the environment in which it is introduced. The sole criteria of reduced levels of atmospheric pollution will not be sufficient justification for development of a fuel-cell car.

Fuel Cell Auxiliary Power Units (APU) are more and more considered as having the potential to improve fuel economy, to be environmental friendly and to add new functions and features to vehicles. There are several APU system architectures combined with different fuels and power levels applied to various vehicles A liquid fuelled APU with a power of 5 kW can address a significant market potential in the field of transportation systems. The future higher voltage architecture and the increasing electrical power demand on board of vehicles are two of several drivers that make the APU solution interesting for many applications. XCELLSIS, The Fuel Cell Engine Company, is developing and manufacturing APUs for automotive application. In this paper, the potential of APUs, their market, and their application, are presented.

The liquid fuel entry into the cylinder and its subsequent behavior through the combustion cycle were observed by a high speed CCD camera in a transparent engine. The videos were taken with the engine firing under cold conditions in a simulated start-up process, at 1,000 RPM and intake manifold pressure of 0.5 bar. The variables examined were the injector geometry, injector type (normal and air-assisted), injection timing (open- and closed-valve injection), and injected air-to-fuel ratios. The visualization results show several important and unexpected features of the in-cylinder fuel behavior: 1) strip-atomization of the fuel film by the intake flow; 2) squeezing of fuel film between the intake valve and valve seat at valve closing to form large droplets; 3)deposition of liquid fuel as films distributed on the intake valve and head region. Some of the liquid fuel survives combustion into the next cycle.

The Hot Isostatic Pressing process on a commercial basis has been applied only to high cost castings (aerospace and racing). Porosity elimination is the application purpose, saving a casting from unacceptable levels of porosity. H.I.P. is very expensive. Manufacturing cost of aerospace and racing castings is very high so H.I.P. is accepted because economically convenient. This paper reviews and discusses: 1) The development of an innovative Hot Isostatic Pressing process named Liquid Hot Isostatic Pressing with the goal to overcame the cost issue of gas H.I.P., 2) L.H.I.P. effect on Mechanical Properties of Treated Specimens vs. not treated and Comparison of Treated Castings vs. not treated, 3) Range of Components this process can be applied to. The potential of high strength, very light and cost effective aluminum casting production can be achieved by utilization of the L.H.I.P. process.

There is a common understanding that hydrogen has a great potential to be the fuel of the future. In addition to the challenge of developing appropriate hydrogen propulsion systems the development of hydrogen storage systems is the second big issue. Due to its high potential in cost and weight and specific storage capacity, the BMW Group is focusing on the development of liquid hydrogen storage systems. In the next hydrogen 7-Series the BMW Group is about to make for the first time the step from demonstration fleets to cars used by external users with a liquid hydrogen storage system. To realize this significant goal, special focus has to be put on high safety standards so that hydrogen can be considered as safe as common types of fuel, and on the every day reliability of the storage system. Moreover, the development of strong partnerships with suppliers is a key factor to realize the design and identify appropriate manufacturing processes.

By fastening the two substrates together prior to sealing, a mated fit of the dry surface is achieved. With proper molding, machining or casting of the substrates a channel is created for an injection of gasketing material to follow, similar to the grove for a hand placed compression gasket. The material developed is flowable enough to fill the entire channel with small injection pressures. Once the channel is filled, the material cures in a very short time. This method allows for varying surface irregularities to be accounted for and sealed easily by the material. The material itself is designed to expand upon thermal exposure and exposure to the fluid it is sealing in or out. This swell then puts pressure within the channel and upon the opposing substrates increasing the seal force and enhancing the seal performance. Materials have been design to seal oils, coolants, water and transmission fluid. Other materials can be designed to meet different and new seal needs.

Liquid injection sealing (LIS) is an innovative sealing technique for the formation of static seals. Where hitherto preformed elastomer gaskets or prior to assembly wet applied sealants are used, LIS can contribute interesting advantages: It combines features both of liquid and preformed gaskets and can be applied within an automated process. Outstanding characteristics are first of all functionality of the sealant and secondly the application process. The sealant itself functions as an expansive sealant. Filling the channel and adapting to all mating surfaces, it forms a seamless seal that fits all assemblies. The seal pressure is generated by thermal expansion and predefined swelling by specific fluids. The second issue is connected to the application methodology: the process allows real-time quality control since injection pressure and volume are monitored. A deviation in sealant volume or in pressure progression reliably indicates faulty components early in the assembly process.