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Diesel engine exhaust aftertreatment components, especially the diesel particulate filter (DPF), are subject to various modes of degradation over their lifetimes. One particular adverse effect on the DPF is the significant rise in pressure drop due to the accumulation of engine lubricant-derived ash which coats the inlet channel walls effectively decreasing the permeability of the filter. The decreased permeability due to ash in the DPF can result in increased filter pressure drop and decreased fuel economy. A unique two-step approach, consisting of experimental measurements and direct numerical simulations using ultra-high resolution 3D imaging data, has been utilized in this study to better understand the effects of ash accumulation on engine aftertreatment component functionality.

The impact of market-fuel variations on the HCCI operating range was measured in a 2.3L four-cylinder engine, modified for single-cylinder operation. HCCI combustion was achieved through the use of residual trapping. Variable cam phasing was used to maximize the load range at each speed. Test fuels were blended to cover the range of variation in select commercial fuel properties. Within experimental measurement error, there was no change in the low-load limit among the test fuels. At the high-load limit, some small fuel effects on the operating range were observed; however, the observed trends were not consistent across all the speeds studied.

This paper presents an overview of the process Cummins uses to integrate the engine and aftertreatment systems with the vehicle. This is a system integration process which assembles various subsystems such as the engine, aftertreatment, drivetrain, electronics, and cooling systems into one vehicular end product. It requires close collaboration with vehicle manufacturers and their suppliers. Given the wide range of vehicle types and applications, a robust process is needed. A synopsis of this vehicle integration process is included.

As fuel prices continue to be unstable the drive towards more fuel efficient powertrains is increasing. For engine original equipment manufacturers (OEMs) this means engine downsizing coupled with alternative forms of power to create hybrid systems. Understanding the effect of engine downsizing on vehicle interior NVH is critical in the development of such systems. The objective of this work was to develop a vehicle model that could be used with analytical engine mount force data to predict the vehicle interior noise and vibration response. The approach used was based on the assumption that the largest contributor to interior noise and vibration below 200 Hz is dominated by engine mount forces. An experimental transfer path analysis on a Dodge Ram 2500 equipped with a Cummins ISB 6.7L engine was used to create the vehicle model. The vehicle model consisted of the engine mount forces and vehicle paths that define the interior noise and vibration.

An ideal industrial tractor is a loader-tractor combination with a high strength, durable frame, good maneuvering characteristics; easy operation; minimum maintenance; and low cost. The design and specifications of such a unit, the International 3414 loader tractor, is described in this paper.

The new 706 and 806 farm tractor series are described, including their appearance, operation, and engine specifications. A new clutch facing pad material is used - a sintered material used in high temperature aircraft brakes. The hydraulic system has three subdivisions: the front pump system, the rear pump system, and the independent power take-off.

The first part of the paper deals with the mathematical model and computer program for simulating a compression-ignition engine. The various assumptions used and the effects of these assumptions on the results are discussed. The second part of the paper evaluates results of the engine simulation program by comparisons with experimental data and with other simplified cycle calculations. The comparisons with experimental data include motoring, part load, and full load data for a speed range of 1400–3200 rpm. The simulation results show good agreement with experimental pressure-volume diagrams. The computed trends of volumetric efficiency, heat rejection, and metal part temperatures show reasonable agreement with experimental data.

Sound power measurements have been widely used as a means of classifying component noise of off-highway equipment. Traditional sound power measurements are accurate and repeatable but require specially designed acoustical rooms. These measurements require removal of the component from the vehicle and a means of powering, loading and monitoring the component. Sound intensity measurements have been proven as a valuable tool in the calculation of sound power. Measurements can be made directly on the vehicle, thus eliminating the need of external power supplies and loading devices. The sound intensity technique is quick, dependable and does not require the use of special acoustical rooms. This paper discusses an example of sound intensity for measurement of hydraulic pump noise. These measurements have been verified using conventional sound power measurements on the same pump.

The direct injection spark-ignition engine is the only internal combustion engine with the potential to equal the efficiency of the diesel and to tolerate a wide range of fuel types and fuel qualities without deterioration of performance. However, this engine has low combustion efficiency and excessive hydrocarbon emissions when operating at light load. In this paper, potential sources of hydrocarbon emissions during light load operation are postulated and analyzed. The placement of fuel away from the primary combustion process in conjunction with a lack of secondary burnup are isolated as important hydrocarbon emissions mechanisms. Analyses show that increasing cylinder gas temperatures can improve secondary burnup of fuel which would reduce hydrocarbon emissions. Practical means to achieve this include higher compression ratio and use of ceramic parts in the combustion chamber.

This paper presents nonlinear system identification of a variable oil pump for model-based controls and diagnostics of advanced internal combustion engines. The variable oil pump offers great benefits over the conventional fixed displacement oil pump in terms of fuel efficiency and functional optimality. However, to fully benefit from the variable oil pump, an accurate mathematical model that describes its dynamic behavior is foundational to develop an accurate and robust oil pressure control and diagnostic. Toward this end, Hammerstein and Wiener models that consist of a nonlinear static block followed by a linear dynamic block and a linear dynamic block followed by a nonlinear static block, respectively are developed. Under different operating conditions (oil temperature and engine speed), the oil pressure (output) is measured with the multilevel duty cycle (input) of the flow control valve.

This paper describes a systematic, physics-based approach in deriving engine performance requirements for a Diesel cold-start catalyst warmup strategy that would satisfy low NOx regulations. These requirements are valid for both conventional and hybrid vehicles. The requirements are driven by an understanding of catalyst and engine behavior. The paper defines a metric that can be used to design and evaluate the performance of technologies, controls and calibration strategies. Optimization strategies based on this metric are proposed. Some examples of the optimization are highlighted.

A Generator set is comprised of mainly an Engine, Alternator and Chassis. High Horse-Power Generator development is challenging, with lots of complexities in physical and virtual validations. Creating high fidelity analytical model is always beneficial and economical at the design stages as it avoids repetitive tests on various design concepts. This paper reports analytical methods of developing an FEA model of a Generator for locomotive application and its correlation with Test. Highlighted as well are some of the challenges faced in FE modeling of a large Generator model (60 liters engine capacity) with node count of around 4 million. In this technique, Modal Analysis is first performed to capture the dynamic behavior. More than 95 % correlation is achieved between the FEA and test natural frequencies (Bending modes). Harmonic Analysis with Modal Superposition is then applied to understand the dynamic response of a Chassis under the action of engine vibratory loads.

The NMFTA’s Vehicle Cybersecurity Requirements Woking Group (VCRWG), comprised of fleets, OEMs and cybersecurity experts, has worked the past few years to produce security requirements for Vehicle Network Gateways. Vehicle Network Gateways play an important role in vehicle cybersecurity – they are the component responsible for assuring vehicle network operations in the presence of untrustworthy devices on the aftermarket or diagnostics connectors. This paper offers security requirements for these gateways in design, implementation and operation. The requirements are specified at levels of abstraction applicable to all vehicle networks down to CAN networks specifically. These requirements were captured using the https://github.com/strictdoc-project/strictdoc requirements management tool and will be made available also as a ReqIF format along with the paper at https://github.com/nmfta-repo/vcr-experiment.