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RADIATION can produce almost instantaneous failure of modern aircraft lubricants, tests at Southwest Research Institute show. Two types of failures demonstrated are rapid viscosity rise and loss of heat conductivity. Furthermore, it was found that lubricants can become excessively corrosive under high-level radiation. Generally speaking, the better lubricants appeared to improve in performance while marginal ones deteriorated to a greater extent under radiation. When the better lubricants were subjected to static irradiation prior to the deposition test, there was a minor increase in deposition number as the total dose was increased.

The purpose of this paper is to construct the thermal analysis model by measuring and estimating the temperature at the traction contact area. For measurement of temperature, we have used a thin-film temperature sensor. For estimation of temperature, we have composed the thermal analysis model. The thin-film temperature sensor was formed on the contact surface using a spattering device. The sensor is constituted of three layers (sensor layer, insulation layer and intermediate layer). Dimensions of the sensor were sufficiently smaller than the traction contact area. The sensor featured high specific pressure capacity and high speed responsiveness. The thermal analysis model was mainly composed of three equations: Carslaw & Jaeger equation, Rashid & Seireg equation and heat transfer equation of shear heating in oil film. The heat transfer equation involved two models (local shear heating model at middle plane, homogeneous shear heating model).

Radioactive tracer technology is an important tool for measuring component wear on a real-time basis and is especially useful in measuring engine wear as it is affected by combustion system operation and lubricant performance. Combustion system operation including the use of early and/or late fuel injection and EGR for emissions control can have a profound effect on aftertreatment contamination and engine reliability due to wear. Liner wear caused by localized fuel impingement can lead to excessive oil consumption and fuel dilution can cause excessive wear of rings and bearings. To facilitate typical wear measurement, the engine's compression rings and connecting rod bearings are initially exposed to thermal neutrons in a nuclear reactor to produce artificial radioisotopes that are separately characteristic of the ring and bearing wear surfaces.

Radioactive tracer technology (RAT) is an important tool in measuring component wear in an operating engine on a real-time basis. This paper will discuss the use of RAT to study and evaluate boundary lubricant and surfactant chemistries aimed at providing benefits in wear control. In particular, RAT was employed to study ring and bearing wear as a function of engine operating condition (speed, load, and temperature) and lubricant characteristics. Prior to testing, the engine's compression rings and connecting rod bearings were subjected to bulk thermal neutron bombardment in a nuclear reactor to produce artificial radioisotopes that were separately characteristic of the ring and bearing wear surfaces. The irradiated parts were installed in the test engine, after which testing to a specific test matrix was accomplished.

Several techniques have been developed to measure the relative amount of splash and spray produced by vehicles when driven on wet roads at highway speeds under controlled conditions. This paper discusses considerations in the development of measurement techniques such as those utilizing photographs, a photometer, densitometer, spraymeter, and spray collector. The development of each technique is described. Some test data utilizing the photometer and densitometer techniques are presented in a comparison of two different trucks run on two different road surfaces with new and worn tires, fully loaded and unloaded, and under light and heavy road moisture conditions.

For viscous couplings(VCs) as a driving force transmission system of vehicles, requirement of torque characteristics has been getting very stringent. Because the torque characteristics significantly affect four wheel drive vehicles' abilities such as traction performance and driving stability. Furthermore, the recent concerns on high fuel economy, low pollution and low cost require that design of VCs should be increasingly compact, light weighted and excellent in transmitted torque's stability. It is an easy way to increase viscosity of viscous coupling fluids(VCFs) for the compact design of the VC. But it might cause increase in heat load and wear of plates which resulted in degradation of the VCF. The degradation affects VCF's viscosity and impairs stability in torque transmission. Therefore it is indispensable to develop high viscosity VCF which is excellent in long-term viscosity's stability.

In the 1st generation Toyota "MIRAI" fuel cell stack, carbon protective surface coating is deposited after individual Ti bipolar plate being press-formed into the desired shape. Such a process has relatively low production speed, not ideal for large scale manufacturing. A new coating concept, consisting of a nanostructured composite layer of titanium oxide and carbon particles, was devised to enable the incorporation of both the surface treatment and the press processes into the roll-to-roll production line. The initial coating showed higher than expected contact resistance, of which the root cause was identified as nitrogen contamination during the annealing step that inhibited the formation of the composite film structure. Upon the implementation of a vacuum furnace chamber as the countermeasure, the issue was resolved, and the improved coating could meet all the requirements of productivity, conductivity, and durability for use in the newer generation of fuel cell stacks.

This paper discusses the techniques and diagnostic significance of atomic absorption, atomic emission, and infrared spectrometric analysis of crankcase lubricants, with the use of supplementary data where pertinent. The parameters affecting used oil analytical data are discussed in terms of examples from Army general purpose vehicle test engines. Wear metals in used gear oils are also discussed and examples are given. Analytical methods and their applications are fully described, and the equipment and procedures for infrared spectroscopy and gas chromatography techniques are outlined.

The reduction of CO2 emissions is one of the most important challenges for the automotive industry to contribute to address global warming. Reducing friction of internal combustion engines (ICEs) is one effective countermeasure to realize this objective. The improvement of engine oil can contribute to reduce fuel consumption by reducing friction between engine parts. Electrification of ICE powertrains increases the overall efficiency of powertrains and reduces the average engine oil temperature during vehicle operation, due to intermittent engine operation. An effective way of reducing engine friction is to lower the viscosity of the engine oil in the low to medium temperature range. This can be accomplished while maintaining viscosity at high temperatures by reducing the base oil viscosity and increasing the viscosity modifier (VM) content to raise the viscosity index (so-called “flat viscosity” concept).

The reduction of the heat loss from the in-cylinder gas to the combustion chamber wall is one of the key technologies for improving the thermal efficiency of internal combustion engines. This paper describes an experimental verification of the “temperature swing” insulation concept, whereby the surface temperature of the combustion chamber wall follows that of the transient gas. First, we focus on the development of “temperature swing” insulation materials and structures with the thermo-physical properties of low thermal conductivity and low volumetric heat capacity. Heat flux measurements for the developed insulation coating show that a new insulation material formed from silica-reinforced porous anodized aluminum (SiRPA) offers both heat-rejecting properties and reliability in an internal combustion engine. Furthermore, a laser-induced phosphorescence technique was used to verify the temporal changes in the surface temperature of the developed insulation coating.

The effects of carbon black∕diesel fuel slurries on fuel injection systems and performance of an EMD 567B two-cylinder locomotive research engine when operated on slurry fuel are presented in this paper. Without extensive modification to the diesel engine fuel transfer system, carbon black slurries cannot be run. Laboratory bench tests revealed clogged fuel filters, worn transfer pump components and frozen injector needle assemblies. Engine performance while running slurries resulted in reduced thermal efficiency and increased BSFC at rated power output. Upon engine disassembly, inspection revealed severe ring and liner wear. Severe wear resulted during only 40 hours of engine operation.

For over a decade and a half, Toyota Motor Corporation has been developing fuel cell vehicles (FCVs) and is continuing various approaches to enable mass production. This study used new methods to quantitatively observe some of the mass transfer phenomena in the reaction field, such as oxygen transport, water drainage, and electronic conductivity. The obtained results are applicable to the design requirements of ideal reaction fields, and have the potential to assist to reduce the size of the fuel cell.

In off-highway applications the engine torque is distributed between the transmission (propulsion) and other accessories such as power steering, air conditioning and implements. Electronic controls offer the opportunity to more efficiently manage the control of the engine and transmission as an integrated system. This paper deals with development of a steepest descent algorithm for maximizing the efficiency of hydrostatic transmission along with the engine in the presence of accessory load. The methodology is illustrated with an example. The strategy can be extended to the full hydro-mechanical configuration as required. Applications of this approach include adjusting for component wear and intelligent energy management between different accessories for possible size reduction of powertrain components. The potential benefits of this strategy are improved fuel efficiency and operator productivity.

SCR-on-filter, or SCRoF, is an emerging technology for different market segments and vehicle applications. The technology enables simultaneous particulate matter trapping and NOX reduction, and provides thermal management and aftertreatment packaging benefits. However, there is little information detailing the lubricant derived exposure effects on functional SCR performance. A study was conducted to evaluate the impact of various oil consumption pathways on a light duty DOC and SCRoF aftertreatment system. This aftertreatment system was aged utilizing an engine test bench modified to enable increased oil consumption rates via three unique oil consumption pathways. The components were characterized for functional SCR performance, ash morphology, and ash deposition characteristics. This included utilizing techniques, such as SEM / EDS, to evaluate the ash structures and quantify the ash elemental composition.

Since the invention of the internal combustion engine, the contact between piston ring and cylinder liner has been a major concern for engine builders. The quality and durability of this contact has been linked to the life of the engine, its maintenance, and its exhaust gas and blowby emissions, but also to its factional properties and therefore fuel economy. While the basic design has not changed, many factors that affect the performance of the ring/liner contact have evolved and are still evolving. This paper provides an overview of observations related to the lubrication of the ring/liner contact.

Galvannealed steel sheet (GA) is very extensively used for vehicle panels. However ζ-phase (FeZn13) in GA coat causes poor stamping formability. Previously, there were no easy methods to evaluate the influence of ζ-phase on the frictional characteristics other than the X-ray diffraction method. This study will discuss the development of a new testing method: Dr. STAMP Method that is both efficient and convenient with pin-on-disc tester.

Two types of new conceptual lead free overlays are developed for automotive internal combustion(IC) engine bearings. The overlays are consisted of molybdenum disulfide(MoS2) and polyamideimide(PAI) resin for binding. One of the overlays is suitable for diesel engines with higher unit load and the other overlay is suitable for gasoline engines with higher sliding velocity. Both overlays indicate good corrosion resistance and wear resistance comparing with conventional lead base overlay. Moreover, higher fatigue resistance is obtained in combination with high performance lead free bearing alloy. These new bearings have the potential to become alternative materials to conventional copper lead bearings with lead base overlay.

The API has established lubricant specifications, which include standard tests for ring and liner wear. The Mack T-10 is one such test, performed on a prototype engine with Exhaust Gas Recirculation (EGR). At EOT, the liner wear is measured by profilometry, while the ring wear is measured by weight loss. It was decided to monitor the wear of the rings and liners during a full-length T10 test in order to observe the evolution of the wears and wear rates over the course of the test, by using the Surface Layer Activation (SLA) and Bulk Activation (BA) techniques. Three different radioisotopes were created, one in the liners at the turnaround zone, one in the chromium-containing coating on the ring faces, and one in the iron bulk of the rings. This enabled us to observe the wear characteristics of these three components separately. In particular, we were able to separate the face and side ring wears, which cannot be done with simple weight-loss measurements.

Modifying the standard Sequence V-D test for alcohol fuels requires material changes in the fuel handling system addition of a fine mesh fuel filter and the provision for easy fuel drainage. Besides rejetting the carburetors the initial ring gaps of the 2.3L engine are reduced to maintain the blow by level of the standard test. Large oil consumption necessitates a modified oil leveling procedure. Precise measurements of the rings bores and valve-train components are essential to the evaluation of oil performance. Wear of a 2.3L engine using alcohols is larger than using gasoline. Special oils can be formulated to mitigate the wear problem. To test the 1.6L engine with the Sequence V-D procedure requires extensive modification to the production carburetor and some plumbing changes of the standard test stand. Load and initial oil charge are scaled to reflect the smaller engine requirements. Wear of the 1.6L engine is less severe than the 2.3L.

A technique for induction-hardening local portions of vehicle body reinforcements press-formed of thin sheet steel has been developed, with the aim of ensuring occupant safety in a side collision. This technique for increasing the tensile strength of sheet steel was practically applied to the front floor cross member and center pillar reinforcement. Owing to this method, the weight of body reinforcements can be decreased. New induction-hardening systems have also been developed for the present technique. One is an apparatus which allows induction-hardening a part with a three-dimensionally curved surface. Another is a straightening quench technique used to retain the same dimensional accuracy as the original press-formed part.