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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.

Improving the automobile fuel economy, it is necessary to measure the power loss of the drive train with high accuracy. The authors propose a new method for measuring the friction loss of automobile drive train. This method is based on the measurement of temperature rise of lubricant due to the friction in a drive train, and allows us to separate the friction loss into the lubricant churning loss and the gear friction loss. Applying the new method to a manual transmission and a rear axle, the friction loss of automobile drive train was measured with much higher accuracy, and effects of the gear ratio, input shaft speed, lubricant temperature, kinematic viscosity and differences of drive train on the friction loss have been revealed.

Studying the formation and distribution of residual stress fields will improve the wheel safety operational criteria among other gains. Many engineering specifications, manufacturing procedures, inspection and quality control have begun to require that the residual stress of a particular component to be evaluated. It is known that these residual stress fields could be added to the effects of a system load (tare weight plus occupation of vehicle, traction, braking and torque combined). The mathematical tools for modeling and simulations using finite elements had evolved following the increasing computing power and hardware cost reduction. On the other hand, the experimental testing, offers specific physical component behavior and with the use of statistical tools, it is possible to predict the real behavior of the component when in operation. The experiments undertaken used the X-ray diffraction technique and the drilling method with rosette type strain gages.

In the exhaust gas after-treatment, it is difficult to evaluate the oxidation process of diesel soot, because we cannot observe the variation of particle size and the number concentration directly. Moreover, characteristics of soot depend on fuel properties, gas component, and engine conditions. Then, we used carbon particles as model soot, and particle size and its number concentration were experimentally measured in the presence of NO2. The particle size was measured by SMPS, together with the measurement of CO and CO2. Results show that, in the presence of NO2, the oxidation rate is close to the value of diesel soot with catalyzed DPF.

An investigation has been carried out to measure the spatial structure of the turbulence in a model IC engine at near to BDC, inlet stroke. Flying hot wire anemometer measurements have revealed details of the effect of the inlet port angle and valve lift on the spatial turbulence structure. Cycle resolved turbulence intensity and integral length scale are presented at three cutoff frequencies of 10 Hz, 100 Hz, and 1000 Hz. Although the situation is transient, conventional analysis methods are shown to be useful. The inhomogeneity of the intake turbulence is found to be considerable. It is also shown that high turbulence energy content occurs at lower frequencies. The flow also exhibits high cycle-to-cycle variation in the mean velocity although this variation was not sensitive to the cutoff frequency. At low cutoff frequency the integral length scale of BDC turbulence was found to be comparable with the valve lift. The rôle of the inlet jet flow is shown to be crucial.

In Diesel injection Systems, cavitation often appears in the injection nozzle holes. This paper analyses how cavitation affects the Diesel spray behavior. For this purpose two spray parameters, mass flux and momentum flux, have been measured at different pressure. We know that cavitation brings about the mass flux choke, but there are few studies about how the cavitation affects the momentum and the outlet velocity. The key of this study is just the measurement of the spray momentum under cavitation conditions.

Structural properties of motorcycle riders are discussed in this paper. First, locations of center of mass and moment of inertia are measured in normal and forward -leaned riding positions. Secondly, two kinds of rider models are proposed, which describe the mechanical motions of rider's body without his control actions. One of these models has two degrees of freedom concerning leaning motion of upper body and lateral movement of lower part. The other describes the yawing motions of upper and lower parts of body. The spring constants and the damping coefficients of human body included in these models are estimated by means of excitation experiments on riders.

The present paper analyses the results from a series of experiments involving tests of catalysts under a stepwise constant engine idle speed schedule in the form of a step pyramid. This test speed schedule consists of an acceleration sequence formed by a number of abrupt speed increments followed by constant speed periods, and a deceleration sequence formed by the same speed changes executed in the reverse order. During the experiments the CO, HC, as well as the catalyst outlet - inlet temperature difference were monitored. The experimental results indicated that as the catalyst efficiency deteriorated with age, the rise of pollution levels was accompanied by significant changes in the CO and temperature difference signals. The HC signal was not as strongly affected. There are positive indications that the outlet - inlet temperature difference signal can be used as an input to a microcontrolled catalyst efficiency assessment system, capable of operating under driving conditions.

Time-resolved mass injection rates of an outward opening piezo-actuated and a solenoid actuated multi-hole GDI injector were measured to investigate (1) the influence of both hardware and software settings and (2) the influence on the injection rates from a wide range of operational parameters and (3) discuss limitations and issues with this measurement technique. The varied operating parameters were fuel pressure, back-pressure, electrical pulse width, single/double injection and injection frequency. The varied hardware/software parameters were injector protrusion, upstream fuel pressure condition and the cut-off frequency of the software's low-pass filter. Signal quality was found to be dependent on both hardware and software settings, especially the cut-off frequency of the low-pass filter. Measurements with high signal quality were not possible for back-pressures lower than 0.5 MPa.

A hydrocarbon trapping system for cold start emissions was constructed and tested using two types of carbonaceous adsorbents provided by Corning, Inc. One was made by combining activated carbon with an organic binder and extruding it into a honeycomb, and the other by depositing a carbon coating on a ceramic monolith. The tests were carried out on an engine in a dynamometer laboratory to characterize the performance of the carbon elements under transient cold start conditions. Performance was evaluated by continuously measuring exhaust gas hydrocarbon concentrations upstream and downstream of the trap, using conventional emissions consoles. Samples were also collected for off-line analysis of individual hydrocarbon species using gas chromatography to examine differences in adsorption of individual species. The speciated hydrocarbon data were used to distinguish between the mass trapping efficiency and a reactivity-based trapping efficiency of the adsorbant traps.

Exhaust emission rates of selected toxic substances were determined for two late model gasoline-powered passenger cars. These substances are listed, or are under review for listing, as toxic air contaminants under California's air toxics program and include volatile and semi-volatile halogenated hydrocarbons, 1,3-butadiene, acrolein, phenols, nitrobenzene, dialkylnitrosamines, and a number of other unregulated emissions. Regulated gaseous emissions and fuel economy were also measured. A literature search was performed to determine if any of these compounds had previously been measured in the exhaust of gasoline-powered vehicles and if appropriate analytical procedures were available. When unavailable, procedures were developed for sampling and analyzing the unregulated toxic emissions. The two vehicles were then tested to determine the emission rates of the targeted compounds.

The transmission of fluidborne pressure and flow pulsations through a hose assembly is dominated by a four-port transfer matrix equation. The potential of pulsation attenuation in the assembly is then related to the four parameters of the matrix by the concept of “Transmission Loss”. The paper presents the development of an accurate test system, based on the “Four Sensors/Two Systems” method, for measuring the transfer matrix and transmission loss of hose assemblies. Particular attention is paid to the solutions to some technical problems encountered during the development and measurement. Then presented is the application of the system to various types of flexible hose with or without tuning cables used in power steering hydraulic systems. The measurements are very valuable for developing the best tuning cable and hose devices, quieter power steering systems as well as the hoses used similarly in other fluid power systems.