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Diesel Cylinder Deactivation (CDA) has been shown in previous work to increase exhaust temperatures, improve fuel efficiency, and reduce engine-out NOx for engine loads up to 3 bar BMEP. The purpose of this study is to determine whether or not the turbocharger needs to be altered when implementing CDA on a diesel engine. This study investigates the effect of CDA on exhaust temperature, fuel efficiency, and turbocharger performance in a 15L heavy-duty diesel engine under low-load (0-3 bar BMEP) steady-state operating conditions. Two calibration strategies were evaluated. First, a “stay-hot” thermal management strategy in which CDA was used to increase exhaust temperature and reduce fuel consumption. Next, a “get-hot” strategy where CDA and elevated idle speed was used to increase exhaust temperature and exhaust enthalpy for rapid aftertreatment warm-up.

The most recent 2010 emissions standards for heavy-duty engines have established a tailpipe limit of oxides of nitrogen (NOX) emissions of 0.20 g/bhp-hr. However, it is projected that even when the entire on-road fleet of heavy-duty vehicles operating in California is compliant with 2010 emission standards, the National Ambient Air Quality Standards (NAAQS) requirement for ambient particulate matter and Ozone will not be achieved without further reduction in NOX emissions. The California Air Resources Board (CARB) funded a research program to explore the feasibility of achieving 0.02 g/bhp-hr NOX emissions.

Historically, heavy-duty diesel (HDD) engine designs have evolved along the path of increased power output, improved fuel efficiency and reduced exhaust gas emissions, driven both by regulatory and market requirements. The various technologies employed to achieve this evolution have resulted in ever-increasing engine operating cylinder pressures, higher than for any other class of internal combustion engine. Traditional HDD engine design architecture limits peak cylinder pressure (PCP) to about 200 bar (2900 psi). HDD PCP had steadily increased from the early 1970's until the mid 2000's, at which point the structural limit was reached using traditional methods and materials. Specific power output reversed its historical trend and fell at this time as a result of technologies employed to satisfy new emissions requirements, most notably exhaust gas recirculation (EGR).

While the engine mount rates need to be optimized to achieve the required frequency alignment and modal decoupling for quality performance, the robustness of the system needs to be studied as well. If a system exhibits acceptable modal characteristics with nominal optimized rates, the sensitivity of the system to variation of the rates from their nominal values affects the robustness of the system. Different factors can cause variation of the rates. Among them are rate changes from part to part arising from manufacturing process. In this paper the effect of mount rates variability on the modal characteristics is discussed. Monte Carlo simulation is used to predict how the rigid body modes and their couplings vary when the rate for each mount changes according to its statistical parameters. Through different examples the statistical variability of the modes to the rates variability is presented.

Commercial vehicles are moving in the direction of improving brake thermal efficiency while also meeting future diesel emission requirements. This study is focused on improving efficiency by replacing the variable geometry turbine (VGT) turbocharger with a high-efficiency fixed geometry turbocharger. Engine-out (EO) NOX emissions are maintained by providing the required amount of exhaust gas recirculation (EGR) using a 48 V motor driven EGR pump downstream of the EGR cooler. This engine is also equipped with cylinder deactivation (CDA) hardware such that the engine can be optimized at low load operation using the combination of the high-efficiency turbocharger, EGR pump and CDA. The exhaust aftertreatment system has been shown to meet 2027 emissions using the baseline engine hardware as it includes a close coupled light-off SCR followed by a downstream SCR system.

Some communication buses are too powerful and expensive for simple digital on/off operations such as activating lights, wipers, windows, etc. For these applications the LIN bus is currently the most promising communication protocol across the world's automotive industry. This paper addresses a study using LIN (Local Interconnect Network) for Ford South America vehicles. This will propose a new electrical architecture designed with LIN network, which will be replacing the conventional rear and front lights cables in Trucks, where other higher protocols, such as CAN, are not cost effective. LIN is a new low cost serial communication system intended to be used for distributed electronic system that will allow gaining further quality enhancement and cost reduction on cables, connectors and switches.

The driver judges his vehicle based on subjective aspects. Vehicle dynamics characteristics including ride and handling have a major impact on this evaluation. For this reason, vehicle manufactures have grown investments in order to improve vehicle dynamics behavior. Subjective evaluation and customer satisfaction research show which dynamic characteristics need to be improved. CAE models, after being validated based on experimental measures, give a good insight on vehicle dynamic behavior and guide change proposals. At end, new subjective evaluations and measures are carried out in order to check the real improvement of CAE proposals. This work shows the use of the described methodology for a pickup vehicle dynamics evaluation. One of the major complains of pickup drives is related to ride quality. Thinking of that feature the evaluation process considers several phenomena, such as abruptness, front topping, front bottoming, head toss and rear aftershake.

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.

An investigation was performed to determine the effects of applying on-highway heavy-duty diesel engine emissions reduction technology to an off-highway version of the engine. Special attention was paid to the typical constraints of fuel consumption, heat rejection, packaging and cost-effectiveness. The primary focus of the effort was NOx, reduction while hopefully not worsening other gaseous and particulate emissions. Hardware changes were limited to “bolt-on” items, thus excluding piston and combustion chamber modifications. In the final configuration, NOx was improved by 28 percent, particulates by 58 percent, CO and HC were also better and the fuel economy penalty was limited to under 4 percent. Observations are made about the effectiveness of various individual and combined strategies, and potential problems are identified.

Commercial vehicles are being developed for long decades in Brazil creating a deep background on manufacturing process. With the current scenario a variety of different vehicles specifications (weight capacity, load distribution, torque, size, etc.) are being required by the market. Joints with bolts and nuts are the engineering solution for the most of the problems found in automotive engineering regarding commercial vehicles. Screw processes were made during the last 150 years. Nowadays current frame modifications on aftermarket are made with arc weld process that affects directly the material properties and the process needs to be performed by critical personal with training and capacity. In addition cost and timing does not fit for the best equation on how to proceed with the modifications. The solution proposed brings more flexibility on frame assemblies that can be extended to other products.

It is projected that even when the entire on-road fleet of heavy-duty vehicles operating in California is compliant with 2010 emission standards of 0.20 g/bhp-hr, the National Ambient Air Quality Standards (NAAQS) requirements for ambient ozone will not be met. It is expected that further reductions in NOX emissions from the heavy-duty fleet will be required to achieve compliance with the ambient ozone requirement. To study the feasibility of further reductions, the California Air Resources Board (CARB) funded a research program to demonstrate the potential to reach 0.02 g/bhp-hr NOX emissions. This paper details the work executed to achieve this goal on the heavy-duty Federal Test Procedure (FTP) with a heavy-duty natural gas engine equipped with a three-way catalyst. A Cummins ISX-12G natural gas engine was modified and coupled with an advanced catalyst system.

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.

Several new or significantly upgraded heavy duty truck engines are being introduced in the North American market. One important aspect of these new or revised engines is their noise characteristics. This paper describes the noise related characteristics of the new DD15 engine, and compares them to other competitive heavy truck engines. DD15 engine features relevant to noise include a rear gear train, isolated oil pan and valve cover, and an amplified high pressure common rail fuel system. The transition between non-amplified and amplified common rail operation is shown to have a significant noise impact, not unlike the transition between pilot injection and single shot injection in some other engines.

As fuel economy becomes increasingly important in all markets, complete engine system optimization is required to meet future standards. In many applications, it is difficult to realize the optimum coolant or lubricant pump without first evaluating different sets of engine hardware and iterating on the flow and pressure requirements. For this study, a Heavy Duty Diesel (HDD) engine was run in a dynamometer test cell with full variability of the production coolant and lubricant pumps. Two test stands were developed to allow the engine coolant and lubricant pumps to be fully mapped during engine operation. The pumps were removed from the engine and powered by electric motors with inline torque meters. Each fluid circuit was instrumented with volume flow meters and pressure measurements at multiple locations. After development of the pump stands, research efforts were focused on hardware changes to reduce coolant and lubricant flow requirements of the HDD engine.

Southwest Research Institute (SwRI) converted two small air-cooled, gasoline engines to operate on LPG (sometimes called propane since propane is LPG's major constituent). Typical two- and four-cycle engines were chosen for this investigation. The two-cycle engine used was a McCulloch string trimmer engine with 28 cc displacement. The four-cycle engine used was an L-head, Tecumseh TVS90 with 148 cc displacement. These are typical of engines found on lower cost lawn mowers and string trimmers. The engines were baseline tested on gasoline, converted to LPG, and tested to determine equivalence ratios at which the engines could be operated without exceeding manufacturers' recommended spark plug seat or exhaust temperatures. Engine startability and throttle response was maintained with the LPG conversion. The emissions of the four-cycle engine were measured following the CARB 6-mode emissions test procedure.

Hydroformed truck frame side rails from circular tubes are studied for gage variations and pre-strain to be used in crash FEA modeling practice. This study provides simplified models that achieve feasible correlation with actual tests. Meanwhile, from plasticity theory we derive a forming equation in conjunction with forming limit diagrams to estimate material properties for hydroformed rails.

Recent surveys of customer satisfaction with full size pickup trucks have raised the standards for passenger comfort and refinement of such vehicles. Customers for this type of vehicle demand performance levels for attributes such as NVH, ride, and handling that previously belonged to luxury passenger cars. Along with the increased passenger comfort, full size pickup trucks must retain a tough image and be as durable as the previous generation trucks. The challenge is to design for NVH performance that can match and surpass many well behaved and “good” NVH passenger cars without any compromise in durability performance. One aspect of “good” NVH is a steering wheel which is free from vibration. As part of the development of a new design for a full sized pick up truck, an NVH subjective rating of 8-9 (10 is maximum) was targeted for the design of steering column/ instrument panel assembly.

The growing competition of the automotive market makes more and more necessary the reduction of development time and consequently, the increase of the capacity to quickly respond to the launching of the competitors. One of the most costly phases on the vehicle development process is the field durability test, both in function of the number of prototypes employed and the time needed to its execution. More and more diffused, the fatigue life prediction methods have played an important part in the durability analysis via CAE. Nevertheless, in order they can be reliable and really being able to reduce the development time and cost, they need to be provided with load cases that can accurately represent the field durability tests. This work presents a CAE approach used for light trucks in order to get a reasonable understanding of component durability behavior due to payload increase. In general, road load data is not available for a new payload condition.

Heavy-duty (HD) internal combustion engines (ICE) have achieved quite high brake thermal efficiencies (BTE) in recent years. However, worldwide GHG regulations have increased the pace towards zero CO2 emissions. This, in conjunction with the ICE reaching near theoretical efficiencies means there is a fundamental lower limit to the GHG emissions from a conventional diesel engine. A large factor in achieving lower GHG emissions for a given BTE is the fuel, in particular its hydrogen to carbon ratio. Substituting a fuel like diesel with compressed natural gas (CNG) can provide up to 25% lower GHG at the same BTE with a sufficiently high substitution rate. However, any CNG slip through the combustion system is penalized heavily due to its large global warming potential compared to CO2. Therefore, new technologies are needed to reduce combustion losses in CNG-diesel dual fuel engines.

This paper discusses the possible impact of the FM tape recorder and servo-hydraulic actuators on the testing of automotive structures. The use of tape recorders and automatic data reduction systems will permit more accurate definition of service conditions and properly “set-the-stage” for laboratory testing. Servo-hydraulic strokers should encourage better laboratory simulation because of their great flexibility. Test set-up time is reduced, fixtures can be simplified and load control is more precise. Simultaneous multiple inputs can be controlled as to amplitude and phase relationships.