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Regulations governing diesel engine emissions into the atmosphere have led to changes in engine design resulting in increased soot loading of the oil. The largest contaminant in diesel engine lubricating oil on a mass percentage basis is soot. A new instrument named LEM, designed to measure the concentration of soot in diesel engine lubricating oil and the existing methods of measuring soot are described. Comparisons of measurements of the amount of soot in diesel engine oil by the test methods have been conducted. The test results are compared to the expected theoretical results to allow a comparison of the accuracy of the test methods.

An optical measurement named the “transmissive light extinction method” was carried out to investigate soot behavior in a diesel combustion chamber. First, the theoretical principle was discussed, and some preliminary experiments to examine the applicability of the method were performed. The method was applied successfully to the measurement of actual soot density in an experimental engine with a facility to observe the inside of the combustion chamber. However, some limitations were noticed in the method, as it was essentially a matter of local measurement. Then a simple but unique optical arrangement was made to enable simultaneous highspeed photographing of shadowgraphs and direct images of the combustion flame. As a result, a total picture of the combustion process, though it was not sufficiently quantitative yet, was obtained, including fuel spray, flame and soot behaviors.

The consistent measurement of airbag deployment noise places special demands on the enclosure in which the measurements are performed. The acoustical characteristics of the enclosure must be stable over long periods. It must also be sufficiently robust to withstand the loads involved. The use of a standardized enclosure provides a uniform basis for comparable measurements in different laboratories. The reasons for selecting a specific small cabin as the standard enclosure are discussed in this paper. Some examples of tests performed in the small cabin with a wide range of airbag systems are presented. High-speed film recordings of the deployment of the airbags were made simultaneously with the acoustic measurements. The stability of the acoustic environment and of the enclosure were important factors in obtaining reliable and comparable results.

Intake, exhaust, and heating / air conditioning systems in automobiles consist of various common duct elements. Noise arises primarily due to the source and is attenuated using common elements like expansion chambers and resonators. This attenuation is straightforward to predict using plane wave simulation and more advanced numerical methods. However, flow noise is often an unexpected important noise source. Predictions require computer intensive analyses. To better understand the aeroacoustic sources in duct systems, a flow rig has been developed at the University of Kentucky. The flow rig consists of a blower, a silencer to attenuate blower noise, external noise sources, and then the test duct. The flow rig can be equipped with an anechoic termination to measure transmission loss or may be used to measure insertion loss directly. In the latter case, the sound power is measured from the pipe outlet inside of a hemi-anechoic chamber.

Dimethyl ether (DME) is a promising alternative fuel for compression ignition (CI) engines. DME features good auto ignition characteristics and soot-free combustion. In order to develop an injection system suitable for DME, it is necessary to understand its fuel properties. Sound speed is an important fuel property that affects the injection characteristics. However, the measurement data under high-pressures corresponding to those in fuel injection systems are lacking. The critical temperature of DME is lower than that of diesel fuel, and is close to the injection condition. It is important to understand the behavior of the sound speed around the critical point, since the sound speed at critical point is extremely low. In this study, sound speed in DME in a wide pressure and temperature range of 1 MPa to 80 MPa, 298.15 K to 413.15 K, including the vicinity of the critical point, was measured. The sound speed in DME decreases as either the pressure falls or the temperature rises.

Several methods have been established to measure the normal incidence transmission loss of noise control materials using the standing wave tube. In the automotive NVH field, multi-layered systems are common-place, for example in the interaction between the traditional mass-decoupler dash insulator and the front dash sheet metal. Most of the sound transmission loss studies utilizing the standing wave tube have so far been focused on single layer systems with only a limited number of studies on multi-layered systems. Therefore there is only some degree of information on the correlation between this said method and the more widely accepted two-room methods of determining sound transmission properties in these systems.

Advanced high strength steels (AHSS) are increasingly used in automotive industry. A major issue for AHSS stamping is edge cracking. This failure mode is difficult to predict by conventional forming limit curve (FLC). The material edge stretchability is mainly evaluated using the hole expansion test. In this study, digital Image Correlation (DIC) is applied for strain measurement. DIC is a non-contact, full field, high accuracy and direct measurement technique that provides more detailed information for the evolution of strains on the sheet surface. Tests were conducted for five AHSS and nine cases. This paper will explain in detail the DIC technique and its results.

This paper presents digital speckle correlation technique to study the strain at the macroscopic level during a tensile test. Digital Speckle Correlation (DSC) is a full-filed and non-contacting optical technique. It offers a significant advantage over conventional techniques such as extensometer for tensile test of materials. It has a high sensitivity and accuracy and thus helps in determining the true mechanical properties of the material for a better understanding of component behavior. From the measured data, we see that the accuracy of the system is sufficient enough to track the initiation and development of strain concentration in the necking region by computing the strain contours in full field environment. True Strain-stress data is presented with a comparison of the measured data with the traditional method. Initiation of the necking region has been identified using the full field data measured.

Structural attenuation of a running diesel engine measured by a new technique showed a constant value regardless of engine speeds. It was verified by this result that structural attenuation is a physical quantity unique to the structure of each engine and, therefore, a good indicator for evaluation of low noise engine structure. In addition, a hydraulic excitation test rig was devised to measure structural attenuation directly and to make effective use of it for noise reduction. Based on the accurate measurements by the excitation test rig, modal analysis and system simulation were conducted for implementation of countermeasures against noise.

Engine research has increasingly focused on emission of sub 23 nm particulates in recent years. Likewise, current legislative efforts are being made for particulate number (PN) emission limits to include this previously omitted size range. In Europe, PN measurement equipment and procedures for regulatory purposes are defined by the particle measurement programme (PMP). Latest regulation drafts for sub 23 nm measurements specify counting efficiencies with a 65% cut-off size at 10 nm (d65) and a minimum of 90% above 15 nm (d90). Even though alternative instruments, such as differential mobility spectrometers (DMS), are widely used in laboratory environments, the interpretation of their sub 23 nm measurements has not yet been widely discussed. For this study, particulate emissions of a 1.0L gasoline direct injection (GDI) engine have been measured with a DMS system for low to medium speeds with two load steps.

The research on health effects of soot particles has demonstrated their toxic impact on humans, especially for the smallest ones that can pass through the lungs into the bloodstream and be transferred to other parts of the body. Since the Euro 5b regulation, the total particle number (PN) at the exhaust is limited, but the associated protocol developed by the Particle Measurement Program (PMP) group defined a counting efficiency at the 23 nm cut-off particle diameter to avoid measurement artefacts [1][2]. Recent studies have demonstrated that the last generation Euro 6 engines can emit as many particles in the range 10-23 nm as beyond 23 nm [3]. The SUREAL-23 project (Understanding, Measuring and Regulating Sub-23 nm Particle Emissions from Direct Injection Engines Including Real Driving Conditions), funded by Horizon 2020 EU-program, aims to develop sampling, conditioning and measuring instruments and associated methodologies to extend the existing protocol down to at least 10 nm.

Foaming of thermoplastic polyolefins (TPO) and thermoplastic elastomers (TPE) is gaining interest because of the lightweight and high performance to weight ratio of foamed automotive parts. Since foaming will occur mainly in the PP matrix in these PP-based automotive materials, understanding of the thermophysical properties of PP/gas mixtures is critically important. This paper will present a proposed methodology for measuring the swelling of polymer/gas mixtures. The preliminary experimental measurement of PP/N2 swelling at elevated temperatures and pressures will be discussed.

ONE of the standards adopted earliest by the Society is the list of taper fittings. This standard was adopted in 1914, and has been in use ever since with little revision. Saying that the indicated method of dimensioning and stating limits for taper fittings is not practical, at least in some cases, the author suggests various methods for expressing the tolerance in terms of the longitudinal position of a basic diameter. Another point brought out is that the sides of the keyway are not parallel to the taper. In the 2-in. size, for instance, if the bottom of the keyway is made parallel to the extreme element of the taper as it existed before cutting the keyway, the depth at the side is computed to be 0.0318 in. at the large end of the taper and 0.0392 in. at the small end, a variation of 0.0074 in. between the two ends.

Temperature distribution as the flame propagated and contacted to the wall of the combustion chamber was measured by real-time holographic interference method, which mainly consisted of an argon-ion laser and a high-speed video camera. The experiment was done with a constant volume chamber and propane-air mixture with several kinds of equivalence ratios. From the experimental results, it can be found that the temperature distribution outside the zone from the surface of the combustion chamber to 0.1mm distance could be measured by counting the number of the interference fringes, but couldn't within this zone because of lacking in the resolution of the used optical system. The experimental results show that the temperature distribution when the heat flux on the wall increases rapidly and when the heat flux shows the maximum value are quite different by the equivalence ratio.

Lithium-ion batteries, which are nowadays common in laptops, cell phones, toys, and other portable electronic devices, are also viewed as a most promising advanced technology for electric and hybrid electric vehicles (EVs and HEVs), but battery manufacturers and automakers must understand the performance of these batteries when they are scaled up to the large sizes needed for the propulsion of the vehicle. In addition, accurate thermo-physical property input is crucial to thermal modeling. Therefore, a designer must study the thermal characteristics of batteries for improvement in the design of a thermal management system and also for thermal modeling. This work presents a purely experimental thermal characterization in terms of measurement of the temperature gradient and temperature response of a lithium-ion battery utilizing a promising electrode material, LiFePO4, in a prismatic pouch configuration.

Taking advantages of high speed RGB video cameras, the two-color method can be implemented with a relatively simple setup to obtain the temporal development of the two dimensional temperature and soot (KL) distributions in a reacting diesel jet. However, several issues such as the selection of the two wavelengths, the role of bandpass filters, and the proper optical settings, etc. should be known to obtain a reliable measurement. This paper, at first, discusses about the uncertainties in the measurement of temperature and KL distributions in the diesel flame by the two-color method using the high speed RGB video camera. Since n-butanol, as an alternative renewable fuel, has the potential application in diesel engines, the characteristic of spray combustion of diesel-butanol blends under the diesel-like ambient conditions in a pre-burning constant-volume combustion chamber is studied.

The measurement of temperatures in pistons was always a very important activity for the people involved in tests and development of engines. The method by NTC's allows this measurement in real time and with great precision.

The Instron Capillary Rheometer, with special extremely fine capillaries, has been used to measure the apparent viscosities of non-Newtonian polymer-thickened multigrade oils at temperatures from 100°F to 320°F and shear rates to 106 sec-1. The same apparatus can produce permanent shear under extreme conditions. Temporary shear data at 100°, 150°, 210°, 280° and 320°F are reported for eight commercial oils and five experimental oils formulated with different VI improvers in the same base oil. Permanent shear data are given for a larger set of oils.

Measurement of thermal emittance of hardanodized coating on aluminium sample at different temperatures from −80°C to +100°C has been made using steady state calorimetric method. The measurement sample consists of two aluminium circular discs hardanodized on all surfaces except on assembly contact areas. A thin circular heater was sandwiched between the discs. The assembled sample was suspended inside a vacuum chamber with LN2 cooled shroud and maintained at different temperature levels using electrical power. The thermal emittance of the sample is determined from the sample equilibrium temperatures and from the elect rical power input. An error estimation has been performed, it shows a maximum uncertainty of ±3.3% on the emittance.

Shearography is an interferometric, non-contact and full field method for direct measurement of first derivatives of deformation (strain). It is relatively insensitive to environmental disturbances and has been proven to be a practical measuring tool for nondestructive testing and evaluation (NDT/NDE). In this paper it has been employed to study the thermal residual strains produced during the reinforcement of a composite to a sheet metal. The reinforced composite is used as an additive to provide extra strength to the sheet metal. The reinforcement process involves gradual heating of the glued composite to a temperature of around 175°C - 180°C and then allowing it cool down to room temperature. During the heating process both the composite and the sheet metal are strained, but during the cooling process some amount of strain is left behind in the sheet metal and it has a key role to play when the product is used for critical parts in automobile and aircraft industries.