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In diesel engines, the cylinder liner is one of the places more susceptible to have cavitation. The cavitation process consists in creation (vaporization) of steam bubbles of liquid, and consequence brusque disappearance (condensation) of the same ones in the liquid. When this disappearance or implosion occurs next to the liner surface provokes erosion of the same one. This phenomenon basically occurs from the liner vibration or strangulation of the water flow, that they provoke high speed of the cooling fluid (equation of Bernoulli) [1]. Along a stream line: In this paper we will analyze how the liner vibration is related to the cavitation process, what is the source and how the easiest way to solve it. The methodology used was: Crank domain analysis, Abusive test, in order to accelerate the failure reproduction, Counter measure check, by vibration analysis & validation, by abusive test.

Motion is not only essential for interacting with the environment but also for its understanding. It has many facets which go beyond simply reaching a goal. Motion information often serves as the basis for inferring interrelationships between events, states and intentions of an acting entity. Observers can often identify persons from afar from their movement alone with only a low resolution view. In this connection it is important to identify dominant factors influencing this sensation. It would also be important to analyze how this understanding of motion relates to our primarily technological, cybernetic understanding of the structure of motion. This paper addresses some issues in this field. By emphasizing the compositional aspect of motion it extends the common technological structuring approach into another dimension. It does not offer a solution but serves as a basis for further discussions. At a first step, a linguistic approach is used for structuring complex motion.

Lining life numerical evaluation is getting increasingly popular. Through numerical simulation, the impacts on lining life due to design changes can be easily evaluated. The numerical approach usually predicts rotor temperature first, and then uses the lining wear versus rotor temperature data derived from physical testing to further assess lining life. Therefore, the success in predicting lining life largely relies on the accuracy of predicted rotor temperature as well as the lining wear versus rotor temperature data incorporated afterwards. In this paper, a 1-D rotor thermal model is presented, which intends to better predict rotor temperature while not dramatically increasing computational time. Furthermore, the inputs that would greatly affect simulation results are discussed. After that, two lining life evaluation examples, which employ the 1-D rotor thermal model, are presented. Finally, the applicability of lining wear versus rotor temperature data is discussed.

New technologies, such as electrified powertrain and autonomous driving solutions, are transforming the automotive industry in such a way that achieving vehicle level performance requirements demands an increasingly intensive and detailed system integration exercise. Validation of the braking system, critical to any vehicle level project, must evolve so that the ever-increasing requirements cascade is answered in a way that ensures the highest level of safety and performance as the industry moves toward a new frontier of features. To support this evolution of integration methodology, critical-to-performance components, such as brake pads, must undergo a transformation in how performance metrics are characterized, communicated, and documented.

Due to the dependence of friction on speed, pressure and temperature at the sliding interface, the same friction material exhibits varying friction characteristics in different brakes. For this reason, lining selection is typically carried out with design-intent brakes to capture the true behavior of friction materials. However, doing so necessitates prototype brakes and entails a long lead-time and high development costs. This paper explores the feasibility of conducting friction, fade, and wear tests on brake dynamometers with readily available surrogate brakes. Both analytical scaling principles and experimental results are presented and discussed.

Accurate measurements of brake friction materials are critical to understanding brake behaviors during testing. Current methods typically utilize a hand gauge (or a machine, in some cases) to sample various discrete points on the brake lining. This approach limits measurements to planar wear characteristics, taper and thickness, and excludes more complex measurements such as cupping. The limited number of points means that a single errant point measurement or the choice of point locations can have a large impact on the reported wear measurement. This paper will describe a method for utilizing a Coordinate Measurement Machine (CMM) fitted with a laser line scanning tool to generate a point cloud of data that can then be compared to an earlier measurement of the same piece or to a math model. This method produces thousands of data points which allows for more accurate volumetric wear calculations and color maps of the entire friction face.

Cavitation formation and development inside Diesel injector nozzles suffering from erosion damage has been investigated using enlarged transparent nozzle replicas and computational fluid dynamics (CFD) simulations. Cavitation erosion has been observed at different locations within the nozzle. These have included the top surface inside the nozzle hole next to its entry, the 3o'clock and 9c'clock hole side-inlets as well as at the needle seat area. Instantaneous and time-averaged high-speed CCD images of cavitation have verified that cavitation erosion sites are found in areas of cavitation bubble collapse. This has been further supported by CFD predictions obtained using the measured injection pressure and needle lift traces, both for the pilot and main injection events. The cavitating flow regimes associated with these erosion sites correspond to geometrically-induced hole cavitation, the string cavitation and the needle seat cavitation, respectively.

Radial lip type exclusion devices of various elastomers and configurations have been available to designers for decades. In recent years the steel-encased polyurethane rod scraper has become popular in the most difficult service environments of hydraulic cylinders on mobile equipment. An adaptation of this proven cylinder component is now extending lubrication intervals and life of critical linkage pins and bushings at oscillating pivot points on off-road construction and materials handling equipment. Its purpose is to exclude foreign material such as dirt, water, stones while retaining lubricants at the pin and bushing interface. The polyurethane material with its high tear strength and abrasion resistance extends seal life. Yet, its configuration allows for lubrication at longer maintenance intervals. Current information is that maintenance intervals have been reduced by ninety per cent.

On August 9, 1995, Environmental Protection Agency (EPA) established the Agency's service information regulations. These regulations, in part, required each Original Equipment Manufacturer (OEM) to either provide enhanced information to equipment and tool companies, or make its OEM-specific diagnostic tool available for purchase by aftermarket technicians. In 2001, Ford Motor Company developed a Microsoft Access database containing tested and verified vehicle data providing necessary module information from Ford Motor Company's specific diagnostic tools. The database was presented to the Equipment and Tool Institute (ETI) during the 2001 ETI Tech Week in Detroit. The format is being considered a recommended practice by ETI, and could be used by any OEM seeking a guideline for providing the necessary On-Board Diagnostics (OBD) protocol information.

Link-X Stability System (“Link-X”) is a control arm geometry that forces the control arms to both locate the tire and control the orientation of the chassis. This is achieved via crossing the control arms in the elevation view without having the control arms touch one another. Link-X inverts the overturning moment at each tire and applies the inverted moments to the chassis. In terms of traditional suspension analysis, this geometry creates a high yet completely stable roll center. Changing the vertical distances between the attachment points on the chassis or the spindle changes the amount of anti-roll generated. Anti-pitch is created by shifting the line of intersection of the control arm planes toward the vehicle's center of gravity.

As a means of controlling vehicle brake pressures for varying axle loads and/or vehicle decelerations, link-less brake deceleration sensing valves are being used in addition to fixed split point and link type load sensing proportioning valves. These valves are a means of optimizing the ratio of front-to-rear wheel retarding forces for the full range of vehicle loadings and decelerations thereby improving brake balance and vehicle stability. The object of this paper is to describe a link-less proportioning valve designed and developed for passenger cars and light trucks. Also, included are dynamic simulation and vehicle test results.

Kinematic synthesis of linkage mechanisms is in a new era. Interactive graphics has allowed designers to optimize solutions from among thousands and thousands of possibilities. This order of magnitude change in the kinematic synthesis method over the "thumb-tack and cardboard approach" is yet another excellent example of computer aided design. The LINCAGES © package demonstrates the modern approach to linkage design.

Faced with competitive environments, pressure to lower development costs and aggressive timelines engineers are not only increasingly adopting numerical simulation techniques but are also embracing design optimization schemes to augment their efforts. These techniques not only provide more understanding of the trade-offs but are also capable of proactively guiding the decision making process. However, design optimization and exploration tools have struggled to find complete acceptance and are typically underutilized in many applications; especially in situations where the algorithms have to compete with existing swift decision making processes. In this paper we demonstrate how the type of setup and algorithmic choice can have an influence and make optimization more lucrative in a new product development atmosphere. We also present some results from a design exploration activity, involving linkage and structural development, of an earth moving machine application.

Several automated redesign methods have been proposed for static linear structures. Those methods that use approximate modes incorporate different length scales into the basis vectors, including the overall geometric scale, the loading scale and possibly vibration wavelength scales. The proposed approach uses Ritz vectors derived from pseudo-loads acting on linked-design-variable regions and hence bring a “redesign scale” into the set of base vectors. The results look promising for cases of redesign where substantial changes are required in regional parameters. As might be expected, “pseudo-force modes” due to loads at a regional length scale are best able to predict response of a structure with changes on that length scale. To date only the “forward” problem has been solved, and the fully automated redesign using nonlinear mathematical programming is underway.

Target setting at Body-In-White (BIW) level is typically done for natural frequencies of global modes. Target values are commonly set based on experience or from benchmark studies with competitor vehicles. A link between these targets at BIW level and the vibro-acoustic targets at Trimmed Body (TB) level is not yet well established. Therefore, it is not always guaranteed that the TB targets will be met when the targets at BIW level are reached. Also, the other way around, not reaching a frequency target for a certain BIW mode does not necessarily imply that TB targets will not be met. Hence, there is a clear need for getting more insights in the relation between BIW dynamic properties and TB vibration behavior. In this paper techniques will be presented that establish the link between BIW and TB dynamic behavior. In addition, a large DOE campaign has been carried out to further link these dynamic properties to specific areas in the body design.

Diagnostic tools and service information are often viewed and developed as separate tools for the automotive technician to use while repairing a vehicle. However, the service technician often uses both of them interactively when diagnosing and repairing a problem on a vehicle. Expert-system technology and electronic information retrieval technology are available to create tools that will help technicians improve their efficiency. However, the ultimate advantage of these technologies is not realized until the two applications are linked together so that they can be used interactively. Selecting the appropriate technologies and linking them together as an integrated system is critical to the ultimate effectiveness, acceptance, and success of the system.

High speed tires were measured on the road and in the lab, both on a rear wheel drive and a front wheel drive vehicle. The tests described refer to standard methods used in the tire industry. They include various tire patterns as well as direction-oriented patterns. Depending upon vehicle type and driven axle, the subjective test result in varying sequences in the main groups of tested parameters - slalom, curve behaviour, handling characteristics and steering response. Static, quasi-static and dynamic measurements on tires were performed in the Semperit lab. The data obtained in the lab did not result in distinct sequences. In case we have to decide which tire is best suited for the intended purpose, the basis for decisions in neither precise nor clear, and conventional engineering mathematics will not suffice. Therefore, “Fuzziness” has to be introduced. The basis of the Fuzzy-Set-Theory is a maximum/minimum principle.

Safety systems must have sound structural performance and, as safety performance targets and vehicle complexity rise to ever higher levels, the impact performance of vehicle structures comes under microscopic scrutiny. Full scale crash tests are used to demonstrate the impact performance of a vehicle's structure but the required number of expensive prototypes may not be available in the early stages of any vehicle programme. Hence a means is required to develop the structural performance under impact loading by using the minimum number of vehicles without reducing quality and performance or increasing costs and development timescales. Based on its experience of crash technology, MIRA has designed, developed and installed a new tool to address this issue, in the form of a barrier load cell array with significantly increased geometric resolution and superior data processing, called the Microcell Barrier.

Modeling and simulation have become integral parts of the engineering process and will assume an even greater role in the years ahead. DoD initiatives like Simulation-Based Acquisition mandate a central role of simulation in systems design and engineering. As system engineers and designers rely increasingly on simulation to address design issues, there is an increasing need to develop integrated simulation and modeling environments to support human factors analysis. This paper addresses how and why it would be beneficial to link human process models to human figure models. We discuss how the linked models promote visualization of human factors design concepts. For example, capturing timing and error information from a human figure model greatly enhances the validity of the human process model. Likewise, using human process models to represent the aspects of the process that do not require a human figure model allows larger, more complex processes to be modeled.

Measurements of the initial values lead to an inverse and mathematically unprecisely formulated problem. A precise definition of an inverse problem is possible. It is to state a mathematical model of a physical process with clearly defined initial and exit values for the system behind the process. One can grasp the idea of an inverse problem by considering the tire as a copy of the objects of nature in a room with observations. Interpretation of nature is generally a result of an inverse problem. On one hand, the tire may be represented through the sensory organs and the nervous system as well as the experiences of the developer''s existing apparatus of the projection of reality. On the other hand, it may be represented by a physical law or a model that can be confirmed or is to be refuted with teh help of suitable measurements.