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To reduce the number and severity of accidents, automakers have invested in active safety systems to detect and track neighboring vehicles to prevent accidents. These systems often employ RADAR and LIDAR, which are not degraded by low lighting conditions. In this research effort, reflections from deer were measured using two sensors often employed in automotive active safety systems. Based on a total estimate of one million deer-vehicle collisions per year in the United States, the estimated cost is calculated to be $8,388,000,000 [1]. The majority of crashes occurs at dawn and dusk in the Fall and Spring [2]. The data includes tens of thousands of RADAR and LIDAR measurements of white-tail deer. The RADAR operates from 76.2 to 76.8 GHz. The LIDAR is a time-of-flight device operating at 905 nm. The measurements capture the deer in many aspects: standing alone, feeding, walking, running, does with fawns, deer grooming each other and gathered in large groups.

Fuel consumption of vehicles has received increased attention in recent years; however one neglected area that can have a large effect on this is the energy usage for the interior climate. This study aims to investigate the energy usage for the interior climate for different conditions by measurements on a complete vehicle. Twelve different NEDC tests in different temperatures and thermal states of the vehicle were completed in a climatic wind tunnel. Furthermore one temperature sweep from 43° to −18°C was also performed. The measurements focused on the heat flow of the air, from its sources, to its sink, i.e. compartment. In addition the electrical and mechanical loads of the climate system were included. The different sources of heating and cooling were, for the tested powertrain, waste heat from the engine, a fuel operated heater, heat pickup of the air, evaporator cooling and cooling from recirculation.

A miniature noncontact torque sensor has been developed to be mounted on an engine for use in engine control systems. The sensor is installed in a last main bearing of the engine crankshaft. The principle is based on the measurement of torque-induced change in magnetic properties of a crankshaft due to the magneto-strictive effect. A new signal processing has also been developed. The method is very superior in linearity and stability of the output signal. Performance of the sensor examined on an engine-dynamometer arrangement is described.

This paper introduces a new measurement technique into the field of engine diagnostics. LlPA (Laser lnduced Photochemical Anemometry) is used to measure velocities and velocity gradients over a chosen plane in a motored two-stroke engine during scavenging. The LlPA technique consists of tracking a phosphorescing grid which is created by laser lines directed into the flow. A 308nm pulsed excimer laser beam is divided into 15 lines which are sent through the appropriate optics to create the grid. The grid energizes the seed chemical that is premixed in the carrier gas. The seed chemical used consists of a mixture of phosphorescent gases with nitrogen as the carrier. The results are not bias by out of plane motions, or the inertia or the charge of particles. In each plane forty-four simultaneous points of data are taken with an approximate grid mesh size of 3mm × 3mm. These measurements are taken over thirty consecutive cycles.

The maximum extent of liquid-phase fuel penetration into in-cylinder gases is an important parameter in compression-ignition (CI) engine design. Penetration of the fuel is needed to promote fuel-air mixing, but over-penetration of the liquid phase and impingement on the bowl wall can lead to higher emissions. This maximum liquid-phase fuel penetration, or “liquid length,” is a function of fuel properties, in-cylinder conditions, and injection characteristics. The goal of this study was to measure and correlate the liquid lengths of fuels with wide physical property variations. The fuels were injected into a large range of in-cylinder temperature (700 to 1300 K) and density (3.6 to 59.0 kg/m3) conditions, at an injection pressure (140 MPa) that is characteristic of those provided by current high-pressure injection equipment.

Fuel wetting in the inlet port of a gasoline engine was studied using Laser-Induced Fluorescence (LIF). The measurements were done directly on the metal wall surface. Quantitative results were be obtained using a special calibration procedure. The sensitivity of the technique was found to correspond to a fuel layer thickness in the order of 1 μm, and the accuracy was estimated to be approx. 10 %. The engine was run on iso-octane, and in order to obtain fluorescence a dopant (3-pentanone) was added to the fuel. Laser light with a wave length of 266 nm was generated by frequency doubling the light from a Nd-YAG laser in two steps. A laser sheet was directed into the intake port and the fuel layer on the wall could be studied along a line on the bifurcation wall. The fluorescence light was detected with an intensified diode-array camera. The measurements from the fuel film thickness were compared with measurements of the total fuel film mass using an A/F response method.

Initial measurements of water vapor temperature using a Fourier domain mode locking (FDML) laser were performed in a carefully controlled homogenous charge compression ignition engine with optical access. The gas temperature was inferred from water absorption spectra that were measured each 0.25 crank angle degrees (CAD) over a range of 150 CAD. Accuracy was tested in a well controlled shock tube experiment. This paper will validate the potential of this FDML laser in combustion applications.

Mixture preparation is a key contributor to both the combustion and emissions in automotive gasoline engines. The air-fuel ratio near the spark plug may have an effect on combustion characteristics since it is related to early flame development. Therefore, cycle resolved measurements of equivalence ratio near the spark plug is particularly important for better understanding of its contribution on combustion and emissions. This paper describes how we determined the in-cylinder equivalence ratio from the measured hydrocarbon concentration near the spark plug using a Fast Response Flame Ionization Detector (FRFID). The procedures established were then applied to a limited range of engine operating conditions, and the cycle resolved equivalence ratio near the spark plug was determined from the measured hydrocarbon concentration.

Total hydrocarbon concentrations in the exhaust products from a constant volume heated spherical combustion bomb have been measured using a flame ionization detector. Results were obtained for methane-air and propane-air mixtures as a function of equivalence ratio, initial pressure, wall temperature and inert gas diluent fraction. Although an effort was made to eliminate all crevice volumes and wall contamination, the results indicate that at initial pressures greater than 1 atmosphere, most of the hydrocarbon came from a crevice which was not perfectly sealed. At initial pressures less than 1 atmosphere, it was possible to correct for this and obtain an estimate of the hydrocarbon mass in the quench layer. For an equivalence ratio of unity and no diluent, the hydrocarbon mass per unit wall area was ≤0.02 μg/cm2.

The effects of surface materials and extent of insulation on the heat transfer to the head of an open-chamber diesel were studied. A large instrumentation plug designed to incorporate plates of various materials on the gas-side surface was utilized with a special research head. Instantaneous rates of heat transfer to the plate gas-side surface were measured. Measurement results obtained with a zirconia plate and an insulated metal plate are compared to data for an uninsulated metal plate. The insulation of the metal plate increased its gas-side surface temperature over the uninsulated case by about the same amount achieved with a 6.35-mm-thick zirconia plate. The magnitude of the surface temperature swing for zirconia is not as high as expected from conduction theory, but is substantially higher than that for the uninsulated metal. Significant reductions of steady state heat fluxes were achieved with both the zirconia and the insulated metal compared to the uninsulated metal.

A detailed investigation of the intake port mixing process was performed on a fired single cylinder port fuel injected research engine. The liquid fuel droplets were studied using several different methods of analysis ranging from spatially and temporally resolved to spatially and temporally averaged data. Comparisons of the port mixture preparation results were made to the combustion performance of the engine in order to develop correlations between the mixing process and resulting engine performance. It is suggested that while the nature of the fuel spray produced by the injector is important, there are several other factors that influence fuel delivery to the cylinder. Calculations are given that indicate drops must be very small to entrain in the flow and avoid wall wetting. Secondary drop formation mechanisms may ultimately determine the nature of the fuel delivery to the cylinder and have an impact on combustion performance.

An experimental and numerical investigation of commercial Gasoline (octane number = 90) with a reference fuel (PRF87) were accomplished. Laminar Flame Velocities and Markstein Numbers of these fuel air mixtures were investigated and compared with each other and with numerical results. PRF87 is presented as a reference fuel for Gasoline defined as 87 percent Iso-Octane and 13 percent N-Heptane by volume at ambient conditions. Spherical flames of Gasoline- and PRF87-Air-Mixtures at initial temperature of 373 K, initial pressure range from 10 bar to 25 bar and equivalence ratios from ϕ = 0.7 to ϕ = 1.2 were experimentally investigated using the Constant Volume Bomb Method.

This paper presents new measurements of liquid and liftoff lengths, vapor penetration, and ignition delay using the Engine Combustion Network (ECN) ‘Spray B’ injector in a 2.34 L skip-fired heavy-duty optical engine. The data from the Spray B injector, having three 90-micron holes, are compared with previously existing constant-volume vessel data using both the Spray B injector as well as the ECN Spray A injector, which has a single 90-micron axial hole. The new data were acquired using Mie scattering, OH* chemiluminescence imaging, schlieren imaging, and incylinder pressure measurements. This paper presents data from estimated isentropic-core top-dead-center conditions with ambient densities of 15.2 and 22.8 kg/m3, temperatures of 800, 900, and 1000 K, and for both non-reacting (0% and 7.5% O2) and reacting (13, 15, and 21% O2) injections of n-dodecane at fuel-rail pressures of 500, 1000, and 1500 bar.

The cycle-resolved fuel concentration near the spark plug in a firing SI engine has been measured using an infrared fiber optic instrumented spark plug probe. The probe can measure in-cylinder concentrations of hydrocarbons in the pre-combustion regions of the engine cycle and give qualitative results for unburned hydrocarbons in the post-combustion regions. The device consists of a spark plug body that has been modified to accept a pair of sapphire optical fibers in addition to a spark electrode. Radiation from an infrared source is coupled into one fiber and reflected from a minor on the spark plug ground electrode to the other fiber which carries the signal to a detector and data acquisition system. The probe measures the attenuation of the infrared radiation transmitted through a region in the vicinity of the spark gap. The attenuation results from the absorption of radiation by the fuel. The measurements were made in a CFR engine at 600 rpm using propane fuel.

This paper describes the theoretical principle for measuring total hemispheric emissivity by a conventional calorimetric method. A sample, whose emissivity is to be measured, is suspended within a vacuum chamber (pressure < 10−7 mbar). The heater-equipped sample radiates to a “cold” thermal environment. In equilibrium state, knowledge of the heater-dissipated electric power, of sample temperatures, and of the environment will yield the total hemispheric emissivity of the area. Optimizing the measurement's delicate transition from theoretical principle to practical implementation was made possible by fine analysis of the error budget related to this experiment, leading on to designing a total hemispheric emissivity bench capable of measurements over the 300 K-to-80 K ranges to within 0.04 and 0.03 accuracies at these respective temperatures.

Few studies have investigated pediatric head injury mechanics with subjects below the age of 8 years. This paper presents non-injurious head accelerations during various activities for young children (2 to 7 years old). Eight males and five females aged 2-7 years old were equipped with a head sensor package and head kinematics were measured while performing a series of playground-type activities. The maximum peak resultant accelerations were 29.5 G and 2745 rad/s2. The range of peak accelerations was 2.7 G to 29.5 G. The range of peak angular velocities was 4.2 rad/s to 22.4 rad/s. The range of peak angular accelerations was 174 rad/s2 to 2745 rad/s2. Mean peak resultant values across all participants and activities were 13.8 G (range 2.4 G to 13.8 G), 12.8 rad/s (range 4.0 rad/s to 12.8 rad/s), and 1375 rad/s2 (range 105 rad/s2 to 1375 rad/s2) for linear acceleration, angular velocity, and angular acceleration, respectively.

While adult head injuries have been studied over the past six decades, few studies have investigated pediatric head injury mechanics. This paper presents non-injurious head accelerations during various activities in a pediatric population. Six males and six females aged 8–11 years old were equipped with a validated head sensor package and head kinematics were measured while performing a series of playground-type activities. Maximum resultant values across all participants and activities were 25.7 g (range 3.0 g to 25.7 g), 16.0 rad/s (range 10.4 rad/s to 16.0 rad/s), and 1705 rad/s2 (range 520 rad/s2 to 1705 rad/s2) for linear acceleration, angular velocity, and angular acceleration, respectively. Mean maximum resultant values across all participants and activities were 9.7 g (range 2.1 g to 9.7 g) and 734 rad/s2 (range 188 rad/s2 to 734 rad/s2) for linear and angular acceleration, respectively.

In automotive air conditioning systems, the oil circulation rate (OCR) is known to affect performance at both the component and system levels. The OCR is the ratio of the mass of the oil in a representative sample of oil-refrigerant mixture from the system to the total mass of the sample taken during steady state operation. With the general industry trend towards low-OCR compressors, the OCR values of interest are getting smaller, and it is becoming increasingly important to acquire an accurate knowledge of OCR for proper system optimization. While there are different OCR measurement techniques available, they all require accurate calibration which is done using the ASHRAE Standard 41.4. The standard describes a sampling technique using an evacuated sampling cylinder with a dead end to draw a sample of oil-refrigerant mixture from the system liquid line.

An investigation into factors influencing top-ring oil film thickness at TDC, in a diesel engine, was carried out using capacitance probes and surface thermocouples installed in the liner. Short term and long term trends in the data were observed, and many unexpected features were found. Significant, consistent differences in the film thickness around the cylinder were detected, and the thermocouples showed that for this engine, the top ring unexpectedly cools the wall for a short time near TDC. Due to irreproducibility of the data, two different data acquisition techniques were used. Acquiring consecutive cycles, for a short period of time, provided a “high resolution snapshot” of the process. This method however, was not sufficient to characterize the data, and it was found that taking non-consecutive cycles, over a longer period of time, provided much more knowledge about the long term trends in the data.

A unique system which allows sampling of the entire contents of one of the cylinders of a 5.7-liter V-8 indirect-injection diesel engine has been developed. An explosively actuated cutter ruptures a diaphragm in the combustion chamber and allows the contents of the cylinder to rush out and be subsequently diluted and quenched with cool nitrogen. Particles are collected with a high-volume impactor/filter system. This system has been used to collect a series of particle samples at crankangles ranging from 5 to 40 degrees after top dead center. Particle samples from the exhaust were also obtained. The samples have been extracted to determine the soluble organic fraction. These extracts have been analyzed for five polycyclic aromatic compounds: pyrene, fluoranthene, benz(a)pyrene, benz(k)fluoranthene, and 1-nitropyrene. The results indicate significant removal of the first four between the combustion chamber and the exhaust manifold.