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The design of intake manifolds and valve ports in internal combustion engines is a fundamental aspect of obtaining high volumetric efficiency and originating in-cylinder flows of proper intensity. CFD calculations using the RANS approach may support steady-state flow measurements in the design of intake manifolds, valve passages, and combustion chambers. On the other hand, the geometrical complexity of these engine parts hardly allows to mesh them by means of fully hexahedral grids and the accuracy of computations is strongly compromised. The paper presents the results of an experimental and numerical study performed on the head of a motorbike high-speed spark ignition engine. The work aims at investigating the reliability of CFD RANS computations performed on polyhedral grids of different size and assessing the mesh size required for accurate computations on such a type of grid.

A laser-induced fluorescence (LIF) system has been developed to obtain measurements of the instantaneous lubricant film thickness in the piston-cylinder assembly of a firing single-cylinder, direct-injection diesel engine. Measurements were made at top-dead-centre (TDC), mid-stroke and bottom-dead-centre (BDC) position by means of three fibre optic probes inserted into the cylinder liner and mounted flush with its surface. Following extensive repeatability tests, the cycle-averaged lubricant film thickness was estimated for different multi-grade oils as a function of engine speed, load and temperature. The results quantified the dependence of the film thickness ahead, under and behind the piston rings on oil chemistry and viscometric properties, thus confirming the important role of the LIF technique in the development and formulation of new engine oils.

We compare measurements of the space radiation environment from particle detectors aboard Mir and Strv-1b (Geostationary Transfer Orbit) with the NASA AE8/AP8 radiation belt models. The two orbits cover a large area of space which allows to test the standard models in a number of key regions and point out their defficiencies.

A hot-wire anemometer was used to study the air motion in a motored i.c. engine. Measurements were made of the mean velocity, turbulence intensity, and integral scales of turbulence. The engine speed was varied from 500 to 2500 rpm, and the hot-wire probe was traversed both across the combustion chamber clearance volume and down into the piston sweep volume. The latter traverse was accomplished by probe-accommodating “wells” built into the piston crown, which were subsequently shown to severely disrupt the flow during the compression and expansion strokes. The results show the mean velocity and turbulence intensity to vary linearly with engine speed, and the turbulence scales to be a function of geometry only. The structure of turbulence was found to be inhomogeneous in the clearance volume and the upper portion of the sweep volume.

This paper reports measurements of the effective tensile strength (or ‘cavitation threshold’), Fc, of Newtonian silicone oils over a range of shear viscosities, and of a multigrade oil over a range of temperatures, T, in the range 20°C ≤ T ≤ 140°C. These measurements are the first to be obtained for a lubricant under dynamic stressing by tension, over a range of temperatures representative of those encountered under its normal operating conditions. This work introduces a method of estimating Fc from direct measurements of static positive pressures: it thereby eschews the reliance in previous related work upon direct measurements of dynamic negative pressures by transducers designed for use in the range of positive pressures.

The three components of the velocity were measured by laser Doppler velocimetry at 35 locations in each of the six intake ports of a single-cylinder I.C. engine motored at 600, 900, and 1200 rpm. The intake ports were designed to impart both swirl and roll to the air. Pressure was also measured at the intake and exhaust. The detailed information is valuable mostly for computations of engine flows and for the assessment of multidimensional models. However the following trends were observed. The intake velocity is affected by resonant pressure waves. The flows in the six ports tend to be similar. The three components of the ensemble-averaged velocity generally have uniform profiles across the port area, whereas the fluctuation intensities are higher at the top of the port. All velocities tend to be higher at the beginning and end of intake.

The flow rate meter based on the Laser Doppler Anemometer (LDA) has been developed to evaluate the fuel injection rate. The flow rate meter is called as LDA flow rate meter. The instantaneous flow rate has been measured at the upstream of an injector. The measured results of instantaneous flow rate are influenced by reflection pressure waves from the end of pipe. The effects of the pressure waves appear as undesirable oscillations in the results of the instantaneous flow rate. A reducing method of the oscillations is proposed as data correction. Corrected data of LDA flow rate meter have similar profiles to the results by the BOSCH-Type injection indicator. The results indicate the instantaneous injection rate can be evaluated by using the LDA flow rate meter.

To remain competitive the United States must change its way of doing business. We must learn to produce the highest quality product at a competitive cost. There are many things that must be done to attain this goal. This paper addresses only one - measurements. The role of measurements in the decision making process will be addressed. The main thrust is the discussion of the elements of a measurement, modeling a measurement and error analysis.

The potentiality in the competition of its products determines the existence and development of a plant by and large. But all in all, it is the competition of talented personnel that has the last word. The cultivation and enhancement of the basic quality of staffs and workers is of primary importance. Some measures adopted in connection with the education of staffs and workers are presented (ESW). The guiding principle in ESW is to lay emphasis on the task of al-post training (APT), and the core of APT is skill training. The efficiency and fruitfulness of the service for the plant is the indisputable criterion for judging whether or not the APT is a success and the efficiency is expressed in the form of promoting productivity, tackling difficult problems and improving skills. Only when the necessary measures are taken can we really enhance the basic quality of the plant through ESW.

The growing awareness of health relevance of fine dust emissions beyond traditional combustion engines becomes more and more important for state of the art research activities. Already existing emission regulations, which are exclusively dedicated to combustion engines, can also be helpful to regulate brake particle emissions since they are nearly in the same range of size and distribution. Another driver is customer satisfaction like surveys such as J.D. Power are showing. It can be stated that a major reason for complaints is the elevated wheel soiling by braking-caused emissions. The major goals of research activities are the development, realization and evaluation of countermeasures dedicated to brake particle emissions. For the development of measures a possibility is shown, which allows the characterization of particle loaded flows as well as the realization of countermeasures. Therefore numerical flow simulation (CFD) is used.

New parameters which characterize aircraft dynamic maneuvering performance in air-to-air combat have been developed. The parameters are functions of both the time to perform the task and the spatial aspects of the maneuver. They have been developed for a point-and-shoot engagement and roll reversal maneuver, although the procedure is sufficiently general that it can be applied to most combat maneuvers. The parameters can be used to predict the outcome of air-to-air engagements and the time advantage that one aircraft has against another aircraft.

Remote diagnostic systems support diagnostic communication by having the capability of sending diagnostic request services to a vehicle and receiving diagnostic response services from a vehicle. These diagnostic services are specified in diagnostic protocols, such as SAE J1979, SAE J1939 or ISO 14229 (UDS). For the purpose of diagnostic communication, the tester needs access to the electronic control units as communication partners. Physically, the diagnostic tester gets access to the entire vehicle´s E/E system, which consists of connectors, wiring, the in-vehicle network (e.g. CAN), the electronic control units, sensors, and actuators. Any connection of external test equipment and the E/E system of a vehicle poses a security vulnerability. The combination can be used for malicious intrusion and manipulation.

Remote diagnostic systems support diagnostic communication by having the capability of sending diagnostic request services to a vehicle and receiving diagnostic response services from a vehicle. These diagnostic services are specified in diagnostic protocols, such as SAE J1979, SAE J1939 or ISO 14229 (UDS). For the purpose of diagnostic communication, the tester needs access to the electronic control units as communication partners. Physically, the diagnostic tester gets access to the entire vehicle´s E/E system, which consists of connectors, wiring, the in-vehicle network (e.g. CAN), the electronic control units, sensors, and actuators. Any connection of external test equipment and the E/E system of a vehicle poses a security vulnerability. The combination can be used for malicious intrusion and manipulation.

Impulsive sound events (i.e. door closing) are often characterized as being undesirably sharp sounding. A high degree of perceived sharpness is normally related to large amounts of high frequency energy relative to the low frequency energy. In this project third octave data generated from a filterbank was used to calculate the center of gravity (cg) of the third octave bands. The result is the frequency corresponding to the centroid of the third octave data. Sounds with substantial high frequency energy have a centroid location that occurs at a higher frequency. The mean of the third octave cg over the duration of the transient event was investigated, in addition to sharpness as defined by Aures [1] and calculated on a commercially available analyzer. Correlation analyses to subjective data indicate that the mean third octave cg and the commercially available method produce comparable results for the vehicle closure sounds studied here.

Particulate emission reduction has long been a challenge for diesel engines as the diesel diffusion combustion process can generate high levels of soot which is one of the main constituents of particulate matter. Gasoline engines use a pre-mixed combustion process which produces negligible levels of soot, so particulate emissions have not been an issue for gasoline engines, particularly with modern port fuel injected (PFI) engines which provide excellent mixture quality. Future European and US emissions standards will include more stringent particulate limits for gasoline engines to protect against increases in airborne particulate levels due to the more widespread use of gasoline direct injection (GDI). While GDI engines are typically more efficient than PFI engines, they emit higher particulate levels, but still meet the current particulate standards.

This paper describes a technique which can accurately measure firing-cylinder full-load absolute pressure during critical intake events, thereby providing useful cylinder-pressure data for valve-timing optimization. To achieve this, an absolute-pressure transducer is connected to a port drilled through the cylinder wall at an axial location uncovered approximately midway through the piston stroke. This placement spares the transducer from thermal shock caused by flame-front impingement upon the diaphragm, since the combustion is normally completed by the crank angle of passage exposure. The described technique was used to study valve-timing and manifold-runner design effects on the intake process of a V-8 engine and to determine thermal-shock magnitudes and their effect on conventionally-measured pumping-loop data.

As the active chassis technology becomes more and more sophisticated, it becomes increasingly important to have a repeatable and objective environment for testing to accelerate the deployment of active chassis control systems. Track testing is a highly subjective and expensive method for testing and validation of active chassis control algorithms. It is often difficult to recreate a critical condition that a vehicle chassis experiences within its possible operation range during track testing. Therefore an environment with capability to create a critical condition in a repeatable and objective manner is highly desirable. This paper presents a repeatable and objective method for developing as well as measuring performance of active chassis systems.

In evaluating appearance of anodized aluminum, the most important kinds of glossiness are commonly termed distinctness of image, bloom, and haziness. To obtain a simple, meaningful set of quantitative numbers, the various kinds of glosses are related to specific portions of a goniophotometric curve. The technique is applicable to mirror-like metal finishes, to etched and patterned metal surfaces, and to ceramic and paint coatings. This method agrees well with visual ratings, is sensitive to minimum visually detectable differences within products, and provides a means for numerically classifying different products without need for material standards for calibration.

We have elicited a reliable Raman spectral signature for glucose in rabbit aqueous humor across mammalian physiological ranges in a rabbit model stressed by recent myocardial infarction. The technique employs near infrared Raman laser excitation at 785 nm, multivariate analysis, non-linear artificial neural networks and an offset spectra subtraction strategy. Aqueous humor glucose levels ranged from 37 to 323 mg/dL. Data were obtained in 80 uL samples to anticipate the volume constraints imposed by the human and rabbit anterior chamber of the eye. Total sample collection time was 10 seconds with total power delivered to sample of 30 Mw. Spectra generated from the aqueous humor were compared qualitatively to artificial aqueous samples and an excitation offset technique was devised to counteract broadband background noise partially obscuring the glucose signature.