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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.

Turbulent premixed natural gas - air flame velocities have been measured in a stationary axi-symmetric burner using LDA. The flame was stabilized by letting the flow retard toward a stagnation plate downstream of the burner exit. Turbulence was generated by letting the flow pass through a plate with drilled holes. Three different hole diameters were used, 3, 6 and 10 mm, in order to achieve different turbulent length scales. Turbulent integral length scales were measured using two-point LDA and the stretching in terms of the Karlovitz number could be estimated from these measurements. The results support previous studies indicating that stretching reduces the flame speed.

Tightening of automotive particulate matter (PM) emission regulations, driven by health concerns over ultrafine (< 100 nm) and nano-sized (< 50 nm) particles, has focused attention on measurement of particle size and number at the tailpipes of diesel engines. This study presents an investigation of PM emissions by number from a Light-Duty Diesel Engine running on low sulphur fuel using different after-treatment systems. PM measurements by number and size were conducted over both transient and steady-state engine conditions using a standard CVS dilution tunnel. A Scanning Mobility Particle Sizer (SMPS), Electrical Low Pressure Impactor (ELPI), Differential Mobility Spectrometer (DMS) and an Engine Exhaust Particle Sizer (EEPS) were used for PM measurements. The performance of each particle size measurement instrument was assessed, and a comparison provided at similar experimental conditions.

New European motor vehicles must comply with emissions regulations which will soon include the exhaust produced during cranking and warm-up, when a catalyst is not active. This paper describes a technique of using rapid acting sampling valves to take measurements from the combustion chamber and exhaust pipe of a spark ignition engine during this period. The samples were analysed for both total hydrocarbons and individual species. Results obtained from an engine operating on propane fuel are presented. The concept of a storage parameter, developed previously from tests on an engine operating at the cyclic repeating condition (CRC) is used to help interpret the measurements. The total hydrocarbons readings show the behaviour of the engine to resemble that of the fully warmed state 15 seconds after start. Using the storage parameter indicates this similarity occurs closer to 50 seconds from start.

Sampling and analysis methods for unregulated exhaust constituents are discussed. Emission results for more than fifteen exhaust constituents from both gasoline- and diesel-powered automobiles are presented. It is shown that the catalytic converter substantially lowers the emission rates of aldehydes, benzene, benzo(a)-pyrene, hydrogen cyanide, and nitrogen dioxide. However, under certain rich-malfunction conditions, small increases in hydrogen sulfide, carbonyl sulfide, hydrogen cyanide, and ammonia occur. Particulate emissions are the primary concern for diesels since other unregulated emissions occur at the same low levels as from gasoline-powered vehicles. It is concluded that although steady improvements in chemical analysis technology have led to the detection of more and more minor impurities in exhaust, none of these substances are emitted at concentrations that can be considered dangerous.

The National Highway Traffic Safety Administration (NHTSA) routinely measures the force exerted on the barrier in crash tests. Thirty-six load cells on the face of the rigid barrier measure the force. This study examines the load cell barrier data collected during recent years of NCAP testing to determine how it can be used to assess vehicle compatibility in vehicle-to-vehicle front-to-side crashes. The height of the center-of-force measured by the columns of load cells is proposed as a metric for quantitatively describing the geometric properties of the crash forces. For front-to-side crashes, the geometric and stiffness properties of frontal structures during the early stages of crush are applicable. Consequently, geometric and stiffness measurements at a crush of 125 mm are presented in this paper. This paper shows the range of the compatibility and stiffness parameters measured on cars, pickups, vans, and multi-purpose vehicles.

An ionization probe head gasket (to IPHG) was used to investigate flame development in a 2.0L I4 engine with two in-cylinder fluid motions. A new technique was developed to display accurate flame contours at 2%, 10% and 50% mass fraction burned crank angles using the measurements of flame arrival time from the ion probes in conjunction with cycle simulations. The flame arrival and burn rate information is used to scale the relationship between flame radius and mass fraction burned from the cycle simulation to create accurate contours of the flame for each cycle. The tumbling motion inside the combustion chamber produced by the production intake ports convected the flame towards the exhaust side of the chamber. The geometry of the flame development was relatively unaffected by changes in speed and load.

The formation of fuel film in the combustion cylinder affects the mixing process of the air and the fuel, and the process of the combustion propagation in engines. Some models of film evaporation have been developed to predict the evaporation behavior of the film, but rarely experimental results have been produced, especially when the temperature is high. In this study, the evaporation behavior of the film of different species of oil and their blends at different temperature are observed. The 45 μL films of isooctane, 1-propanol, 1-butanol, 1-pentanol, and their blends were placed on a quartz glass substrate in the closed temperature-controlled chamber. The shape change of the film during evaporation was monitored by a high-speed camera through the window of the chamber. First, the binary blends film of isooctane and one of the other three oils were evaporated at 30 °C, 50 °C, 70 °C and 90 °C.

For the case of the in-plane vibration of a plate, the power is carried by shear and longitudinal waves generating an in-plane two-dimensional displacement field. The objective of this paper is to propose experimental techniques for the measurement of the in-plane vibration intensity (power flow per unit width of a cross section) of the plate. The theoretical basis is outlined for the experimental techniques. The experimental techniques have been implemented to measure the in-plane vibration intensity in the plate. The experimental results of the in-plane vibration intensity in the plate have been compared with the theoretical results. It is shown that the experimental techniques can be effectively used to measure the in-plane vibration intensity in the plate.

It is generally accepted that thermal (Zeldo'vich) chemical kinetics dominate NO formation in diesel engines, so control of temperature is critical for reducing exhaust NOx emissions. Recent optical engine data revealed that when the start of injection (SOI) was retarded to very late timings, combustion luminosity decreased while exhaust NOx emissions increased, causing a “NOx bump.” This data suggested that changes in radiative heat transfer from soot may affect in-cylinder temperatures and subsequent NOx formation. In this study, soot thermometry measurements of in-cylinder temperature and radiative heat transfer were correlated with exhaust NOx to quantify the role of radiative heat transfer on in-cylinder temperatures and NOx formation. The engine was operated at low-load conditions, for which the premixed burn was a significant fraction of the total heat release.