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Abstract Three-dimensional patterns representing crosshatched plateau-honed cylinder bores based on two-dimensional Fast Fourier Transform (FFT) of measured surfaces were generated and used to calculate pressure flow, shear-driven flow, and shear stress factors. Later, the flow and shear stress factors obtained by numerical simulations for various surface patterns were used to calculate lubricant film thickness and friction force between piston ring and cylinder bore contact in typical diesel engine conditions using a mixed lubrication model. The effects of various crosshatch honing angles, such as 30°, 45°, and 60°, and texture heights on engine friction losses, wear, and oil consumption were discussed in detail. It is observed from numerical results that lower lubricant film thickness values are generated with higher honing angles, particularly in mixed lubrication regime where lubricant film thickness is close to the roughness level, mainly due to lower resistance to pressure flow.

A new type of screw pump has inherent design features (e.g. balanced design, low bearing loads, wear-adjustable rotors, low rubbing loads, …) which may allow efficient, reliable, and maintainable operation in numerous applications, particularly for pumping low-viscosity fluids. Initial tests on an 87 gal/min prototype pumping lubricating oil at pressures up to 500 lb/in2 and speeds up to 1800 rev/min achieved good performance with little wear over 3400 hours of operations. Performance projections indicate volumetric efficiencies of 50 percent should be reached using the existing prototype pumping 1200 lb/in2 water in one stage.

Anybody knows that contamination in oil is always harmful to hydraulic and lubricating systems. Contaminants inevitably exist in the oils of hydraulic and lubrication systems and cause tribological problems. In order to prevent such tribological problems due to contaminants, various oil cleaners have been developed and applied to hydraulic and lubricating systems. They have greatly contributed to improving the reliability of the systems. Since sophisticated hydraulic systems with proportional valves or servo valves, which are sensitive to oil contamination, became popular, fine filters like 3 micron or 1 micron are additionally used. However contamination problems have been revived. The authors have investigated the causes of hydraulic and lubricating problems and found that polymerized oil oxidation products were as harmful as solid particles. They are of molecular size and cannot be removed by mechanical filtration.

Abstract Due to the incoming phase out of fossil fuels from the market in order to reduce the carbon footprint of the automotive sector, hydrogen-fueled engines are candidate mid-term solution. Thanks to its properties, hydrogen promotes flames that poorly suffer from the quenching effects toward the engine walls. Thus, emphasis must be posed on the heat-up of the oil layer that wets the cylinder liner in hydrogen-fueled engines. It is known that motor oils are complex mixtures of a number of mainly heavy hydrocarbons (HCs); however, their composition is not known a priori. Simulation tools that can support the early development steps of those engines must be provided with oil composition and properties at operation-like conditions. The authors propose a statistical inference-based optimization approach for identifying oil surrogate multicomponent mixtures. The algorithm is implemented in Python and relies on the Bayesian optimization technique.

The objective of this paper is to delineate the importance of pictures, i.e., graphical models, in documenting and communicating the high level functionality of a complex system, primarily for embedded software requirements and specifications. An overview is given of various graphical techniques and methodologies for modeling complex systems. The aspects (advantages and disadvantages) relating to different categories of modeling are outlined. Discussion of complex systems extends beyond the functional/software aspects of product design to both process and project modeling. The author shares personal observations and experiences with modeling, and tools used.

The performance of radial lip seals in either vehicular or industrial applications is a significant factor in the perceived quality of products. Lubricant leakage is high on the list of customer complaints or dissatisfaction. Radial lip seal suppliers have been working closely with vehicle manufacturers to improve the performance of their products. Much progress has been made. Advances from this point will depend not only on improvements in sealing technology but also on improvements in the control of the entire sealing system.

Extensive testing was performed on both the ring-gear and hypoid-gear churning used to move the oil in the axle bowl to lubricate tandem axles. The gear pump test results were used to establish the pump characteristics, as well as the volumetric and mechanical efficiencies. The churning test results were used to formulate an empirical model used in an analysis to predict the energy loss. All testing was done with SAE 90W and 140W lubricants. The results from these experiments, along with some analytical formulations, were used and incorporated into a computer program. The results of the component testing showed that the hypoid-gear churning loss is a large energy loss, amounting to as much as 1.5 horsepower per axle. Since the energy losses in the gear pump amounted to only 0.2 horsepower, around a one horsepower savings per axle is achievable by lubricating the entire axle with the gear pump.

Low heat rejection engine (LHRE) technology reduces the heat transfer from the gases in the cylinder of an internal combustion engine by insulating the walls of the combustion chamber. This technology has the potential for gains in fuel efficiency, cooling system size decrease, the use of alternative fuels, etc. Research on many experimental LHRE's has been reported in the literature. However, these engines have used ceramic material and they have two major problems that need to be overcome. They are: (1) the need for a high temperature lubrication system, and (2) brittleness of the ceramics. To overcome these limitations, a novel LHRE design has been developed in this study. In this design, a high temperature superalloy HAYNES®230™ (USN N06230)' is used instead of ceramics, and conventional low temperature lubrication can be employed. A 3.5 HP one cylinder low heat rejection Diesel engine was developed in this study and tested for 1001 hours without failure.

Effective requirements elicitation and management is a common need in supplier-OEM relationships, and continues to play a vital role in all aspects of the product development lifecycle. While traditional methods address the business goals for requirements and provide guidance in ensuring the accuracy of the “Descriptive-Prescriptive-Explanatory” outputs for requirements gathering and documentation, engineering organizations continue to encounter challenges with respect to capturing and communicating change, accommodating the addition of relevant design details and efficient propagation to inform development. These challenges become more difficult to overcome in mechatronic systems, which combine mechanical systems with integrated software. As software development can produce an overwhelming volume of information that requires accurate tracking and proliferation, it cannot be effectively managed using traditional hardware-centric systems.

Increased awareness of preserving the environment has motivated the development of a wide variety of environmentally compatible products. Such products include environmentally compatible lubricants. Sale and use of these types of lubricants illustrates diligence by the lubricant manufacturer, original equipment manufacturer (OEM), and the consumer in contributing to a cleaner environment. The use of this type of lubricant could enhance the image of the lubricant manufacturer and vendor as well as the equipment manufacturer who employs such a fluid. To base such a lubricant on a vegetable oil creates a product environmentally friendly by its farming origin and its ability to readily biodegrade if released. No machinery is so uniquely suited to using vegetable oil based lubricants as agricultural equipment. Since this equipment is particularly close to the environment, the lubricant can easily come in contact with the soil, ground water, and crops.

The thermal behavior of the electric axle is an essential indicator which requires certain attention during the development process. Due to the complexity of heat generation mechanism and heat transfer boundary conditions, it is difficult to accurately predict the axle’s temperature, especially in real driving conditions. In this paper, a comprehensive 1D model is developed to simulate its heat transfer process effectively and accurately. The heat transfer model is developed based on the thermal network method, and the electric axle is divided into thermal mass according to its heat transfer characteristics. The heat generation model, which accounts for meshing loss, bearing loss, churning loss, and windage loss, exchanges heat flux and oil temperature information with the heat transfer model to take into account the effect of lubricating oil temperature on power loss.

A new Artificial Intelligence (AI) “Expert System” software technology has been developed which shows real promise as the core platform of the Decision Support System for Truck Repair. The “Expert system” consists of a Model Based reasoning mechanism, and a Rule Based shell along with an on-line documentation and graphics capability. This technology combines the development speed and accuracy of Model Based technology, the precision of Rule Based expert systems along with the ease-of-use associated with a “Hypertext” information system.

Low crew productivity and extension of service intervals past design limits are the two major reasons so many heavy equipment PM programs are ineffectual. ALPM, or Assembly Line Preventive Maintenance is an innovative system for equipment servicing, providing management scheduling tools and the necessary controls. The system has a successful track record in a number of severe applications.

Determining pre-impact acceleration and braking performance values is an important aspect of reconstructing collisions. Collision analysts may have to rely upon performance testing of an exemplar vehicle for reliable data to use in traffic collision reconstruction cases. These performance characteristics are well documented for many vehicle classes, but are limited when discussing urban transit style buses. The constant stop and go urban driving conditions in which they operate constantly challenge the vehicle components. Because of the heavy weights and operating conditions, auxiliary braking systems are often installed to prolong the life of the service brakes. A series of idle acceleration, maximum acceleration, and maximum braking tests were conducted using urban transit style buses that are currently in-service in a large metropolitan area. The initial braking target speed for these braking tests was 64 kph (40 mph).

The analysis and description of field generated containment in fluid systems (hydraulic or lubricating oil, fuels, water, etc.) continues to be one of the best indicators of system “health.” The monitoring of the contaminant provides an effective health measure by accurate determination of the contributing factors to system degradation. These include solid particles, water, additive depletion, and a host of resultant synergistic effects such as sludges, gels, etc. Their are many options available for field fluid analysis. Five specific analyses have been found to provide an extensive description of field contaminants. They are particle counting, gravimetric level analysis, proton induced X-ray emission (PIXE) analysis, ferrographic wear debris analysis, and water content analysis. Thorough descriptions of this procedures is provided with detailed application considerations.

This SAE Recommended Practice establishes minimum performance requirements for new pneumatic valves when tested in accordance with the test procedure outlined in SAE J1409. The performance requirements will include: a Input-output performance b Leakage characteristics c Low temperature performance d Elevated temperature performance e Corrosion resistance performance f Endurance testing g Structural integrity

This SAE Recommended Practice establishes minimum performance requirements for new pneumatic valves when tested in accordance with the test procedure outlined in SAE J1409. The performance requirements will include: a Input-output performance b Leakage characteristics c Low temperature performance d Elevated temperature performance e Corrosion resistance performance f Endurance testing g Structural integrity

This SAE Recommended Practice establishes minimum tolerance requirements for pilot operated and mechanically actuated modulating type valves, and through type valves used in the service brake control system when tested in accordance with the test procedure outlined in SAE J1859. This document applies to the nominal input-output characteristics as specified by vehicle original equipment manufacturer and labeled by the valve manufacturer as outlined in SAE J1860. The tolerance requirements will include: a Crack (opening) pressure or force. Crack pressure may be measured at the initial output pressure or as the pressure differential before output pressure exceeds 14 kPa (2 psi). Crack force may be measured at initial output pressure or before output pressure exceeds 14 kPa (2 psi). b Pressure differential (input-output)

This SAE Recommended Practice establishes minimum tolerance requirements for pilot operated and mechanically actuated modulating type valves, and through type valves used in the service brake control system when tested in accordance with the test procedure outlined in SAE J1859. This document applies to the nominal input-output characteristics as specified by vehicle original equipment manufacturer and labeled by the valve manufacturer as outlined in SAE J1860. The tolerance requirements will include: a Crack (opening) pressure or force. Crack pressure may be measured at the initial output pressure or as the pressure differential before output pressure exceeds 14 kPa (2 psi). Crack force may be measured at initial output pressure or before output pressure exceeds 14 kPa (2 psi). b Pressure differential (input-output)