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Pouch cells are increasingly popular form factors for the construction of energy storage systems in electric vehicles of all classes. Knowledge of the stress generated by these higher capacity pouch cells is critical to properly design battery modules and packs for both normal and abnormal operation. Existing literature predominantly offers data on smaller pouch cells with capacities of less than 10 Ah, leaving a gap in our understanding of the behavior of these larger cells. This experimental study aimed to bridge this knowledge gap by measuring loads and stresses in constrained 65 Ah pouch cells under both cycling and abuse conditions. To capture the desired responses, a load cell was located within a robust fixture to measure cell stress in real time after the application of a preload of approximately 30 kilograms or 294 N, equivalent to a pressure of 0.063 bar, with a fixed displacement.

There has been an ongoing interest in replacing mineral oil with more biodegradable and/or fire-resistant hydraulic fluids in many mobile equipment applications. Although many alternative fluids may be more biodegradable, or fire-resistant, or both than mineral oil, they often suffer from other limitations such as poorer wear, oxidative stability, and yellow metal corrosion which inhibit their performance in high-pressure hydraulic systems, particularly high pressure piston pump applications. From the fluid supplier's viewpoint, the development of a definitive test, or series of tests, that provides sufficient information to determine how a given fluid would perform with various hydraulic components would be of interest because it would minimize extensive testing. This is often too slow or prohibitively expensive. Furthermore, from OEM's (original equipment manufacturer's) point of view, it would be advantageous to develop a more effective, industry accepted fluid analysis screening.

The cost of human natural language translation of Service Information, Assembly Instructions, Training Materials, Operator Manuals and other similar documents is a major expense for manufacturers. One translation avoidance method involves replacing most of a document’s text with still and/or animated graphics. While the graphics with minimum text concept has savings potential, clarity of communication must be maintained for widespread application of this technique. The necessary clarity should be achieved if standards are established for the symbols and graphical conventions used. This paper provides an example of a repair procedure documented using the graphics with minimum text paradigm, describes many of the anticipated standards and provides an update on the progress towards achieving a standard development project.

In any machinery, avoiding noise and vibration completely is a difficult task due to the structural dynamic behaviors of components. To safeguard the operator, it is important to best isolate the operator station from NVH environment. Cabin isolation is an important aspect to minimize structure borne noise and tactile vibrations to be transferred into the cabin. Isolators are selected based on the isolation system inertial properties at mounting locations in the operating frequency range interested. The most important assumption to select isolators are that the active side and passive side of the isolators are nearly rigid so impedance mismatch is created for effective isolation. This paper describes the importance of dynamic stiffness of the structures on both the active and passive side for better NVH performance.

The U.S. Army's National Automotive Center has contracted with Illinois Institute of Technology Research Institute (IITRI), Southwest Research Institute (SwRI), and Advanced Propulsion, LLC, to evaluate the effects on fuel consumption and logistics that would result from hybridizing the powertrains of the Army's tactical wheeled vehicle fleet. This paper will outline the approach taken to perform that evaluation and present a synopsis of results achieved to date.

Most of the history of systems engineering has been focused on processes for engineering a single complex system. However, most large enterprises design, manufacture, operate, sell, or support not one product but multiple product lines of related but varying systems. They seek to optimize time to market, costs of development and production, leverage of intellectual assets, best use of talented human resources, overall competitiveness, overall profitability and productivity. Optimizing globally across multiple product lines does not follow from treating each system family member as an independently engineered system or product. Traditional systems engineering principles can be generalized to apply to families. This article includes a multi-year case study of the actual use of a generic model-based systems engineering methodology for families, Systematica™, across the embedded electronic systems products of one of the world's largest manufacturers of heavy equipment.

Light-weight 3-D models offer improved communication and visualization for advertising, marketing, service technicians, suppliers and other business partners. These models also may be a ready source of geometry and a window into a company's intellectual property for miscreants seeking to pirate designs and to produce counterfeit or will-fit parts. What approaches and tools are available to help protect a company's intellectual property while enabling it and its business partners to benefit from widespread distribution of 3-D animations and models? How should they be applied to effectively protect intellectual property? This paper provides a general survey of techniques available for protecting intellectual property in 3-D models when sending these files outside of a company and into broad distribution.

Increased concern for improving fuel mileage in today's vehicles has focused attention on powertrain component efficiencies. Currently, no efficiency standards exist for automatic transmissions but, uniform testing procedures do exist. Consequently, vehicle and transmission manufacturers have no basis for comparing transmission-to-transmission performance. In addition, manufacturers have no design targets from which to critique their product. This paper addresses this issue by developing an overall transmission efficiency rating. This rating is based upon average transmission operational torques and speeds, the percent time of operation in each gear for a representative duty cycle, and representative efficiencies at these conditions based on test data obtained from a cross section of current production transmissions.

The purpose in doing probabilistic structural analysis is to provide the designer with a more realistic ability to assess the importance of uncertainty in the structural response. This paper provides an overview of the methodology and discusses validation of modular structural analysis packages capable of predicting the probabilistic response distribution for key structural variables such as stress, displacement, natural frequencies, buckling loads, transient responses, etc. The structural analysis solution is in terms of the cumulative distribution function (CDF). Probabilistic structural analysis methods (PSAM) can be used to estimate structural safety and reliability, while providing the engineer with information on the confidence that should be given to the predicted behavior.

Upcoming regulations from CARB and EPA will require diesel engine manufacturers to validate aftertreatment durability with full useful life aged components. To this end, the Diesel Aftertreatment Accelerated Aging Cycle (DAAAC) protocol was developed to accelerate aftertreatment aging by accounting for hydrothermal aging, sulfur, and oil poisoning deterioration mechanisms. Two aftertreatment systems aged with the DAAAC protocol, one on an engine and the other on a burner system, were directly compared to a reference system that was aged to full useful life using conventional service accumulation. After on-engine emission testing of the fully aged components, DOC and SCR catalyst samples were extracted from the aftertreatment systems to compare the elemental distribution of contaminants between systems. In addition, benchtop reactor testing was conducted to measure differences in catalyst performance.

It is generally recognized chat methanol is the best candidate for long-term replacement of petroleum-based fuels at soma time in the future. The transition from an established fuel to a new fuel, and vehicles that can use the new fuel, is difficult, however. This paper discusses two independent investigations of possible transition uses of methanol, which, when combined, may provide an option for introduction of methanol that takes advantage of the existing industrial base, and provides economic incentives to the consumer. The concept combines the intermediate blends of methanol and gasoline (50%-70% methanol) with the Flexible Fuel Vehicle. In addition to a possible maximum cost effectiveness, these fuels ease vehicle range restrictions due to refueling logistics, and mitigate cold starting problems, while at the same time providing most of the performance of the higher concentration blends.

The dual-fuel combustion process of ethanol and n-heptane was characterized experimentally in an optically accessible engine and numerically through a chemical kinetic 3D-CFD investigation. Previously reported formaldehyde PLIF distributions were used as a tracer of low-temperature oxidation of straight-chained hydrocarbons and the numerical results were observed to be in agreement with the experimental data. The numerical and experimental evidence suggests that a change in the speed of flame propagation is responsible for the observed behavior of the dual-fuel combustion, where the energy release duration is increased and the maximum rate of pressure rise is decreased. Further, an explanation is provided for the asymmetrical energy release profile reported in literature which has been previously attributed to an increase in the diffusion-controlled combustion phase.

Building on two decades of expertise, a fourth generation fleet test protocol is presented for assessing the response of engine performance to gasoline additive treatment. In this case, the ability of additives to remove pre-existing deposit from the intake systems of port fuel injected vehicles has been examined. The protocol is capable of identifying real benefits under realistic market conditions, isolating fuel performance from other effects thereby allowing a direct comparison between different fuels. It is cost efficient and robust to unplanned incidents. The new protocol has been applied to the development of a candidate fuel additive package for the North American market. A vehicle fleet of 5 quadruplets (5 sets of 4 matched vehicles, each set of a different model) was tested twice, assessing the intake valve clean-up performance of 3 test fuels relative to a control fuel.

In 2020, CARB adopted the low NOX omnibus ruling, which provided revisions to on-road heavy duty engine compliance standards and certification practices. As part of the updates to the regulation, CARB has introduced a new in-use vehicle testing process that broadens the operation modes tested and considers the manufacturer’s intended vehicle application. Compared to the previous method, or the Not-to-Exceed approach, cold start and low ambient temperature provisions were included as part of the updates. The inclusion of low temperature operation requires the OEMs to design a robust engine and aftertreatment package that extends NOX conversion performance. The following work discusses the NOX emissions performance impact in a low temperature ambient environment. The engine and aftertreatment system evaluated was designed to comply with CARB’s low NOX regulations. The cycles tested included the CARB Southern NTE cycle and an FTP-LLC protocol.

The NOx reduction performance under lean conditions over γ-alumina was evaluated using a micro-reactor system and a non-thermal plasma-equipped bench test system. Various alumina samples were obtained from alumina manufacturers to assess commercial alumina materials. In addition, γ-alumina samples were synthesized at Caterpillar with a sol-gel technique in order to control alumina properties. The deNOx performances of the alumina samples were compared. The alumina samples were characterized with analytical techniques such as inductively coupled plasma (ICP) emission spectroscopy, temperature programmed desorption (TPD) and surface area measurements (BET) to understand physical and chemical properties. The information derived from these techniques was correlated with the NOx reduction performance to identify key parameters of γ-alumina for optimizing materials for lean-NOx and plasma assisted catalysis.

High-speed movie films, and laser-diffraction drop sizing were used to evaluate the structure, penetration rate, cone angle, and drop size distribution of diesel sprays in a constant volume pressure vessel. As further means of evaluating the data, comparisons are made between the film measurements, and calculations from a dense gas jet model. In addition to the high-speed film data that describes the overall structure of the spray as a function of time, a laser diffraction instrument was used to measure drop size distribution through a cross-section of the spray. In terms of the growth of the total spray volume (a rough measure of the amount of air entrained in the spray), spray impingement causes an initial delay, but generally the same overall growth rate as an equivalent unimpeded spray. Agreement between measurements and calculations is excellent for a diesel spray with a 0.15 mm D orifice and relatively high injection pressures.

Technical groups worldwide have been actively developing specifications and requirements for biodegradable hydraulic fluids for mobile applications. These groups have recognized that an industry-wide specification is necessary due to the increase in environmental awareness in the agriculture, construction, forestry, and mining industries, and to the increasing number of local regulations primarily throughout Europe. Caterpillar has responded to this need by publishing a requirement, Caterpillar BF-1, that may be used by Caterpillar dealers, customers, and industry to help select high-performance biodegradable hydraulic fluids. This requirement was written with the input of several organizations that are known to be involved with the development of similar types of specifications and requirements.

The key words in the marketplace for off-highway vehicles are durability, performance, and efficiency. A manufacturer of these vehicles recognizes that one way to successfully address these needs is by a well thought through electronics design. With the computer sophistication now being incorporated into off-highway vehicles, engineers must work closely to assure electromagnetic compatibility (EMC) of the entire system. A properly established EMC program extending from concept to final design will support each of a product's specified operations and still function as an integrated whole. This paper describes the process for designing the EMC for an off-highway vehicle.

Twelve different hole shapes for diesel injector tips were characterized with DF-2 diesel fuel for spray cone angle over a range of injection pressures from 21 MPa (3 kpsi) to 69 MPa (10 kpsi). A baseline and two of the most radical designs were also tested for drop-size distribution and liquid volume fraction (liquid fuel-air ratio) over a range of pressures from 41 MPa (6 kpsi) to 103 MPa (15 kpsi). All hole shapes were circular in cross-section with minimum diameters of 0.4 mm (0.016 in.), and included converging and diverging hole shapes. Overall hole lengths were constant at 2.5 mm (0.098 in.), for an L/d of 6.2. However, the effective L/d may have been less for some of the convergent and divergent shapes.

Southwest Research Institute (SwRI) utilizes the burner-based Exhaust Composition Transient Operation LaboratoryTM (ECTO-Lab) to accurately simulate transient engines and replicate real exhaust that is produced by light and heavy-duty engines for aftertreatment aging and evaluations. This system can generate and dose NOX over transient cycles from a range of 20 ppm to 1200 ppm where the NOX is generated by the in-situ decomposition and combustion of a fuel-bound, nitrogen containing compound. During the combustion and decomposition of the nitrogen containing compound over 95 % of the NOX generated is in the form of NO. To authentically simulate exhaust gases, it is necessary to account for the distribution of the NO to the NO2. Since previous work has established that the decomposition of nitric acid can be utilized as a method to generate NO2, the objective of this project was to develop control of NO and NO2 within SwRI’s ECTO-Lab through the decomposition of nitric acid.