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The three velocity components and turbulence intensity were measured at the valve curtains around the two inlet valves of a four-valve s.i. engine with a pent-roof chamber. The measurements were made using hotwire anemometry in a steady-flow rig. Data were collected over a wide range of valve lifts and flow rates. The results show that the velocity profiles are strongly dependent on the valve lift and the surrounding geometry but almost insensitive to the flow rate. Flow separations are identified at certain azimuthal locations for large valve lifts. The turbulence intensity varies around the valve peripheries and across the valve gaps, as do the exit angles of the issuing flows. Their profiles are affected by flow separations from the valve seats and faces and by flow interferences between the two inlet valves. These detailed profiles can be used as boundary for multi-dimensional in-cylinder flow models.

Engine valves must operate in engines with very low failure rates. Long-term durability testing is expensive. This cost could be reduced by running only a final successful proof test, provided adequate data existed to demonstrate that potential life and failure modes have been identified and eliminated by short-term tests and analysis. This approach was applied to a 1983 DDA Model 4-53 engine valve. The results are used to estimate valve life and, further, to estimate the effects of tolerance variations on valve life. The techniques used to determine valve temperatures and strains at nominal and unusual operating conditions in firing engines are presented. The experimental study shows that combustion strains and closing strains are caused by two different loading conditions which affect different portions of the valve head, and also shows how these loads vary with their governing parameters. The theoretical basis for these observations and trends is also presented.

Conventional measuring systems are not able to measure the exactly valve timing on real engines. Due to their requirements, the measurement procedure and consequently their accuracy there are variances, which have a great influence on the measurement results. For an improvement of the gas exchange and finally the engine characteristics it is necessary to develop a new way to get the real valve timing on operating engines. Therefore the University of Applied Sciences Hannover developed a new measurement system to detect the exactly valve timing on real operating engines. This method uses the valve and the valve seat ring as an electrical switch, which is reached by an insulation of these parts against each other. The result is that the valve timing, the length of the opening time, valve overlapping and effects like valve bouncing are able to detect by this new measurement system.

The concentration of gasoline vapors was measured in the breathing zone of a person. refueling automobiles in both summer and winter. The concentrations of total hydrocarbons ranged from 5 to 1220 ppmC in summer and from 4 to 3210 ppmC in winter. Individual values were affected by wind speed and direction, as well as by body shielding caused by the refueler. Compared to the dispensed gasoline, the refueling vapors were enriched in hydrocarbons with normal boiling points below about 125°F, so that five light paraffins (n-butane, isopentane, iso-butane, n-pentane, and propane) constituted more than 70% of the total carbon in the vapors. The combination of the resulting low concentration of the heavier hydrocarbons in the vapor and the rapid dispersal and dilution of the vapor plume minimizes the brief exposure of refuelers to benzene and the C7, and C8 isoparaffins.

Global ethanol trade is forecast to increase 25-fold by 2020. Most of it will be blended with gasoline to make biofuel. However, blending ethanol with gasoline has a profound effect on the evaporation characteristics of the mixture. In particular, the thermodynamic properties of the blends can be significantly different than the constituents. A clear understanding of the blend's properties is essential for optimizing engine design, e.g. utilizing charge cooling effect. Data available in the literature is very limited, considering ethanol-gasoline blends will be used as a fuel in large scale worldwide. In this work, comprehensive measurements of vapor pressures were carried out. The enthalpies of vaporization were derived from vapor pressure data using the Clausius-Clapeyron equation. Maximum vapor pressure occurs with 20% ethanol-gasoline blend at which a positive azeotrope is formed. The trend is different in enthalpy of vaporization.

The antenna is an essential part of any audio system. The three quantities that characterize an antenna are gain, impedance, and antenna pattern. The purpose of this paper is to show how the antenna pattern is related to audio system performance and to describe how antenna pattern measurments are performed.

Soft tissue neck injury has become the most frequent type of injury sustained in motor vehicle accidents. Most of these injuries occur in rear-end impacts. Consequently, vehicle head restraint geometry has become an important issue in vehicle design and injury prevention. Vehicle crashworthiness and safety ratings are published by auto insurers around the world including ICBC, the Insurance Corporation of British Columbia (Canada), the Insurance Institute for Highway Safety (U.S.A.) and the New Car Assessment Program (Australia). These vehicle ratings include head restraint ratings based on static measurements of head restraint geometry. The authors developed a device for measuring head restraint geometry used in these ratings, and detail the results of measurements for 40 current vehicles in North America.

The more stringent regulations issued by the brazilian environmental agency CONAMA, regarding the controlling of vehicular noise emissions, indicates the use of the national standard NBR9714. The application of the criteria described in this standard to the normal procedures for fleet control is discussed in this work. Computer simulations are used to analyse the environmental influences to be expected. Actual measurements are done to validate the simulation results. An integrated system to automate the measurements and the report generation is presented.

A Constant Volume Sampler (CVS) compatible auto exhaust particulate sampling system has been built and successfully operated. The system can be used to sample exhaust isokinetically at constant temperature, yields internally consistent results, and can be operated conveniently and frequently. Studies with the sampling system have shown that vehicles equipped with oxidation catalysts convert some of the sulfur in the gasoline to sulfuric acid containing particulates. Bound water was shown to be a major component of the sulfuric acid exhaust particulate. Catalyst type and system design are believed to have a marked effect on the sulfuric acid conversion with additional research required to determine what features result in lower sulfate emissions. Emission tests have shown that platinum emission rates are lower than 2 × 10-5 g/mi. More sensitive analytical techniques will be required to obtain information on a more quantitative basis.

A set of safety-relevant performance qualities for the passenger car has been defined as a first step in the development of objective measures of precrash safety performance. Measures were sought that stress the performance produced by a passenger vehicle when it is operated under emergency crash-avoidance conditions. This goal has led to the identification of six limit maneuvers and associated limit responses to serve as a first-order means of assessing the safety quality of a motor vehicle. The viability and the discriminatory power of the proposed test procedures have been demonstrated by applying these procedures to four separate vehicles.

This study attempts to predict the effect of visual impairment from simulated levels of splash and spray on target vehicle identification distances. Five levels of hand held spray simulation frames were used to compare image digitization methods with visual performance (Snellen acuity or contrast sensitivity) assessment to predict a drivers ability to identify an oncoming target vehicle. The image digitization process was found to be highly correlated with actual target vehicle identification distances. Additionally, very high correlations were found between Snellen acuity and contrast sensitivity and identification distance. There did not seem to be any great difference in predictive power of either method of visual performance assessment over the other.

Among the various methods for measuring flow velocity vectors, multi-holed pitot tubes offer the advantages of facilitating pressure measurements, low cost and ease of use. On the negative side, the range of measurable flow angles is limited (e.g., to ± 40° with 5-hole tubes) and pitot tubes require time-consuming calibration before use. The authors have developed a new pitot tube with a spherical head and 13 holes arranged such that the pitot head shows a 5-hole pattern when viewed from different right angles. This hole arrangement is equivalent to having several multi-holed pitot tubes connected to one pitot head and expands the measurable range of flow angles substantially to ± 135°. In addition, a robot is used to achieve fully automatic calibration. These two improvements overcome the traditional drawbacks of multi-holed pitot tubes.

This paper reports on a non-intrusive method for measuring the liquid fuel film thickness in the intake manifold of a series production SI engine with multi-point fuel injection. The technique is based on laser-induced fluorescence. The optical set-up uses a bifurcated optical fibre bundle for transmission of the laser light for excitation of the fluid and for detecting of the fluorescence light. Due to the special design of the optical probe head it is highly sensitive for thin film measurements and it allows the accurate determination of the fuel film thickness even between a few and 100 μm. Special emphasis is placed on the selection of an adequate tracer added to the iso-octane fuel to achieve the correct film thickness even under vaporizing conditions, and on a detailed study of the parameters influencing the evaluated film thickness.

Aim of this article is to evaluate cavity ringdown spectroscopy (CRDS) as a suitable technique for the measurement of particulate matter concentration in diesel exhaust. The second harmonic of a Nd:YAG laser was used for pulsed cavity ringdown measurements of the optical extinction of diesel particulate matter. The investigation was carried out at the exhaust of a single cylinder prototype engine, derived from the Euro IV version of FIAT 1.9 JTD M-Jet 16V. Several steady state test points were investigated, corresponding to low and medium load conditions in the European emission test schedule for light duty cars. Unconventional diesel combustion regimes, aimed to get lower flame temperatures and overcome the NOx -soot trade off, have been also investigated.

The propagating flame in a 2-stroke gasoline engine under WOT or transient operating conditions was measured with up to 12 ion probes. Flame arrival time data obtained from multiple-ion probes were statistically compared between arrival time data obtained by different ion probes or between data obtained by the same ion probe for different cycles to investigate the spatial and temporal characteristics of flame propagation behavior. Spatial statistical data analysis revealed that the propagating flame is strongly influenced by the in-cylinder flow prior to ignition. Temporal statistical data analysis revealed that the state of flame propagation, starting from any given cycle and continuing in subsequent cycles, shows a tendency similar to that of the initial cycle for some time, and that the original tendency is completely lost after about 50 cycles.

The r-value is a very important parameter in the forming simulations of high strength steels, especially for steels with prominent anisotropy. R-values for sheet steels conventionally measured by extensometers were found neither consistent nor accurate due to difficulties in measuring the width strain. In this study, the Digital Image Correlation (DIC) technique was applied to determine r-values in Longitudinal (L), Transverse (T) and Diagonal (D) directions for cold rolled DP980 GI, DP780 GI, DP600 GI and BH250 GI sheet steels. The r-values measured from DIC were validated by finite element analysis (FEA) of a uniaxial tensile test for BH250. The simulation results of the load-displacement for two plasticity models were compared to experimental data, with one being the isotropic yield (von-Mises) and the other being an anisotropic model (Hill-48) using the r-value measured from DIC.

Driver’s hands modify the vibrational response of the steering wheel, hence car manufacturers are used to measure vibrations of the free steering wheel to ensure reproducibility. However, levels measured in this condition do not represent those perceived by the driver. The aim of this study is to predict the vibrational response of the hand-wheel coupled system from measurements of the non-held steering wheel, and of the mechanical impedance of the arm. The measurement of the biodynamic response (BR) of the hand-arm system has been studied many times in the bibliography and tested according to the position of the arm, the coupling force, the excitation level or the measurement protocol used. These extensive measurements have resulted in the ISO 10 068 standard and mechanical representation such as mass-spring-damper models, also presented in the ISO standard. A wide review of the literature is carried out and the most suitable model for driving is chosen.

Federal Motor Vehicle Safety Standard (FMVSS) 213 specifies a bench seat that is used in dynamic testing of child restraint systems. To assess the representativeness of the FMVSS 213 bench, data from 54 passenger cars, minivans, and SUVs were analyzed to quantify the side-view profile of the seat centerlines in second-row, outboard seats. SAE J826 H-point measurements were performed on all seats and on the FMVSS 213 bench. A landmark-based resampling method was used to obtain a meaningful average seat contour after aligning on H-point. Principal component analysis and regression were conducted to quantify the effects of seat cushion angle, cushion length, and back angle on the seat profile. When aligned on H-point, the cushion length and surface angles of the FMVSS 213 bench were similar to the mean contour, except that no seats were as flat as the bench profile.

Exhaust emissions and particulate matter (PM) from an engine with a conventional continuous regeneration diesel particulate filter (DPF) were measured to evaluate DPF performance under the Japan 13-mode cycle, European Stationary Cycle and various transient cycles: U.S. transient cycle, Japan Automobile Research Institute cycle, and World-wide Heavy Duty Cycle. The emission tendencies with and without DPF under these conditions were clarified. According to these experiments, accumulated PM in the DPF under the driving modes mentioned above has influence on measurement errors. It is necessary to estimate the amount of accumulated PM in the DPF to evaluate the PM reduction rate correctly. This study also measured particle size distribution of diesel exhaust particulates (DEP) downstream of the DPF using an electrical low-pressure impactor (ELPI). As a result, we determined that most of the particles not trapped by the DPF are less than 110nm.

This paper discusses the analysis and measurement of the dynamic centre of pressure of a brake pad during a normal braking event. The technique is unique in its design and implementation. The process is progressive whereby the interface static measurements are first taken and then dynamic testing is carried out under braking. Two different measurement systems are considered during the analysis with one used to measure the center of pressure. Both the in-board and out-board pads are measured for wear but the piston pad was selected for pressure measurements. Validation of the spragging process is undertaken on both test rigs and vehicle trials. Pad wear measurements complement the collective information. The results show the position of the centre of pressure to vary considerably during a braking event, both radially and axially along the pad.