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A new electric powertrain and axle for light/medium trucks is presented. The indoor testing and the simulation of the dynamic behavior are performed. The powertrain and axle has been produced by Streparava and tested at the Laboratory for the Safety of Transport of the Politecnico di Milano. The tests were aimed at defining the multi-physics perfomance of the powertrain and axle (efficiency, acceleration and braking, temperature and NVH). The whole system for indoor tests was composed by the powertrain and axle (electric motor, driveline, suspensions, wheels) and by the test rig (drums, driveline and electric motor). The (driving) axle was positioned on a couple of drums, and the drums provided the proper torques to the wheels to reproduce acceleration and braking. Additionally a cleat fixed on one drum excited the vibration of the suspensions and allowed assessing NVH performance. The simulations were based on a special co-simulation between 1D-AMESIM and VIRTUAL.LAB.

Low temperature Diesel exhaust operations such as during low-load cycles are some of the most difficult conditions for SCR of NOx. This, along with newer regulations targeting substantial reduction of the tailpipe NOx such as California-2024/2027 NOx regulations, adds to challenges of high efficiency SCR of NOx in low temperature operations. A novel design, low-cost, low-energy Electrically Heated Mixer (EHM™), energized via the 12, 24 or 48 V vehicle electrical system, is used to accelerate formation of reductants (ammonia, isocyanic acid) in low temperature exhaust (low load cycles), so to enable high efficiency SCR of NOx in most challenging SCR conditions, while also mitigating urea deposit formation. EHM™ is also used to heat the cooler exhaust flow during engine cold-start. It easily fits common exhaust configurations and can be utilized on light, medium or heavy duty Diesel aftertreatment systems, on- or non-road or in stationary systems.

A family of high-accuracy, solid-state instruments ideally suited for internal combustion engine and vehicular applications has been developed. The core of each instrument is a programmable custom integrated circuit which produces exceptionally precise performance in applications as demanding as off-road equipment. The instruments are compatible with any form of resistive, voltage or current-producing sensor. Instrument outputs include displays in light emitting diode or liquid crystal formats and electronic signals for remote warning or equipment shutdown. Inherently rugged construction permits operation in sustained high-shock and high-vibration environments over wide temperature ranges. Improvements over existing products are delivered at comparable costs.

Exhaust gas air-fuel ratio (A/F) sensors are common devices in powertrain feedback control systems aimed at minimizing emissions. Both resistive (using TiO2) and electrochemical (using ZrO2) mechanisms are used in the high temperature ceramic devices now being employed. In this work a new mechanism for making the measurement is presented based on the change in the workfunction of a Pt film in interaction with the exhaust gas. In particular it is found that the workfunction of Pt increases reversibly by approximately 0.7 V at that point (the stoichiometric ratio) where the exhaust changes from rich to lean conditions. This increase arises from the adsorption of O2 on the Pt surface. On returning to rich conditions, catalytic reaction of the adsorbed oxygen with reducing species returns the workfunction to its original value. Two methods, one capacitive and one thermionic, for electrically sensing this workfunction change and thus providing for a practical device are discussed.

A new method for detecting the low power conditions on electronically-controlled diesel engines used in on-road vehicles has been developed. The advantage of this method is that it uses readily available diagnostic tools and engine installed sensors with no necessity for a dynamometer test. Without removing the engine, it gives an estimate of the real engine power which is accurate to 5%.

To reduce heat transfer between hot gas and cavity wall, thin Zirconia (ZrO2) layer (0.5mm) on the cavity surface of a forged steel piston was firstly formed by thermal spray coating aiming higher surface temperature swing precisely synchronized with flame temperature near the wall resulting in the reduction of temperature difference. However, no apparent difference in the heat loss was analyzed. To find out the reason why the heat loss was not so improved, direct observation of flame impingement to the cavity wall was carried out with the top view visualization technique, for which one of the exhaust valves was modified to a sapphire window. Local flame behavior very close to the wall was compared by macrophotography. Numerical analysis by utilizing a three-dimensional simulation was also carried out to investigate the effect of several parameters on the heat transfer coefficient.

The reduction of particulate emissions from diesel engines is one of the most challenging problems associated with the exhaust air pollution control. Particulate emissions can be controlled by the adjustments of the combustion parameters of a diesel engine but these measures result in increased emissions of oxides of Nitrogen.Diesel particulate Filters (DPF) hold out the prospects of substantially reducing regulated particulate emissions but the question of the reliable regeneration of filters still remains a difficult hurdle. Many of the solutions proposed to date suffer from high engineering complexity, cost, thermal cracking, increased backpressure which in turn deteriorates diesel engine combustion performance. This paper presents an improved computer aided analytical approach for controlling Diesel soot particulate emission by Cyclone separator. Reduction of soot particles in the exhaust in turn reduces the Diesel Particulate Matter formation.

The design and development of a new four-stroke two-cylinder diesel engine family of 1.29 litre capacity for off road are discussed. The engine is in naturally aspirated and turbocharged and intercooled versions and rated from 11.9 kW/1500 rpm to 25.7 kW/2500 rpm. The engines were tuned for air and fuel flows, air utilisation, fuel air mixing, performance and emissions at steady state at a development lab and later certified in national labs. The high altitude capability of the TCIC was checked using a model. The engines rated at less than 19 kW satisfy India Generator set and off road norms of India and Europe equivalent to USTier4 standard, and at higher ratings, standard equivalent to US Tier4-interim. In the second part of the paper, the design of coolant and oil pumps, oil cooler for TCIC engine and the piston with steel oil control ring are discussed. The higher loaded TCIC engines use fillet hardened crankshafts of chromium molybdenum steel.

The performance of five positive k-factor injector tips has been assessed in this work by analyzing a comprehensive set of injected mass, momentum, and spray measurements. Using high speed shadowgraphs of the injected diesel plumes, the sensitivities of measured vapor penetration and dispersion to injection pressure (100-250MPa) and ambient density (20-52 kg/m3) have been compared with the Naber-Siebers empirical spray model to gain understanding of second order effects of orifice diameter. Varying in size from 137 to 353μm, the orifice diameters and corresponding injector tips are appropriate for a relatively wide range of engine cylinder sizes (from 0.5 to 5L). In this regime, decreasing the orifice exit diameter was found to reduce spray penetration sensitivity to differential injection pressure. The cone angle and k-factored orifice exit diameter were found to be uncorrelated.

Underwater bulldozers have been built for development of the ocean floor. Yet it is impractical for a diver to operate an underwater bulldozer from within the vehicle. Remote control of a bulldozer is extremely difficult due to complicated relationships between vehicle inclination, blade cylinder deflection, and the terrain profile in front of the bulldozer. In this paper a nonlinear automatic feedback blade control system is designed to replace direct operator control of the blade. To accomplish this design, mathematical models were developed for the vehicle dynamics and the hydraulic system dynamics of a typical bulldozer. Since both subsystem models are complicated nonlinear ones, the blade control system was designed using only a simplified hydraulic system model. The performance of the complete nonlinear system with the blade feedback control system added was then investigated using a hybrid computer simulation compared to available experimental data using a skilled operator.

In this paper, computation fluid dynamics (CFD) simulations are employed to describe the effect of flow parameters on the formation of soot and NOx in a heavy duty engine under low load and high load. The complexity of diesel combustion, specially when soot, NOx and other emissions are of interest, requires using a detailed chemical mechanism to have a correct estimation of temperature and species distribution. In this work, Multiple Representative Interactive Flamelets (MRIF) method is employed to describe the chemical reactions, ignition, flame propagation and emissions in the engine. A phenomenological model for soot formation, including soot nucleation, coagulation and oxidation with O2 and OH is incorporated into the flamelet combustion model. Different strategies for modelling NOx are chosen to take into account the longer time scale for NOx formation. The numerical results are compared with experimental data to show the validity of the model for the cases under study.

The objective of this study was to evaluate iso-butanol (C4H9OH) as an alternative fuel for spark ignition engines. Unlike methanol (CH3OH) and ethanol (C2H5OH), iso-butanol has not been extensively studied in the past as either a fuel blend candidate with gasoline or straight fuel. The performance of a single cylinder engine (ASTM=CFR) was studied using alcohol-gasoline blends under different input parameters. The engine operating conditions were: three carburetor settings (three different fuel flow rates), spark timings of 5°, 10°, 15°, 20°, and 25° BTDC, and a range of compression ratios from a minimum of 7.5 to a maximum of 15 in steps of one depending on knock. The fuels tested were alcohol-gasoline blends having 5%, 10%, 15%, and 20% of iso-butanol, ethanol, and methanol. And also as a baseline fuel, pure gasoline (93 ON) was used. The engine was run at a constant speed of 800 RPM.

By coupling a Personal Computer to process 1/0 hardware and adding realtime multitasking software, a low cost automated data acquisition and control system can be assembled. This paper describes such a system built in a 19 inch rack on wheels which has been used for diesel engine testing. The system is readily reprogrammable to customize the function of the system to the job at hand.

Compacted Graphite Iron (CGI) has been recognized for years as a unique material possessing a fortunate combination of properties intermediate between gray iron and ductile iron. This material, for reasons outlined in this paper, is ideal for cylinder blocks, heads and other cast iron components for diesel engines. It makes possible casting weight savings of up to 1/3 and/or increased power output. This paper will outline reasons why this is now possible, whereas it has seldom been applied in volume production heretofore. Physical and mechanical properties of CGI, which provide the opportunity for weight reduction and increased power, are discussed. Currently, most diesel engine cylinder blocks, heads, liners and many other castings are produced from gray iron, which requires relatively heavy sections to provide the strength, stiffness and durability necessary for commercial application.

This paper presents a preliminary study to estimate, using on-road and laboratory tests, the mileage range of liquefied petroleum gas (LPG) as an alternative fuel for diesel-fed public utility jeepneys in the Philippines. Data from the study would be used by the Philippine Department of Energy to formulate and implement alternative fuel programs for public transport. On-road fuel consumption, load factor, and GPS speed data from selected in-use LPG and diesel jeepneys plying a chosen urban route were gathered to develop corresponding drive cycles for chassis dynamometer testing at 100% load factor were conducted to estimate an upper limit for fuel consumption. Measured on-road diesel jeepney mileage was about 6.7 km/liter at 63.5% load factor while that for LPG jeepney was 3.8-4.2 km/liter at 59.8% load factor. Drive cycle tests yielded 5.2 km/liter for diesel and 2.6-3.1 km/liter for LPG.

A Rankine cycle system with ethanol as the working fluid was developed to investigate the fuel economy benefit of recovering waste heat from a 10.8-liter heavy-duty (HD) truck diesel engine. Recovering rejected heat from a primary engine with a secondary bottoming cycle is a proven concept for improving the overall efficiency of the thermodynamic process. However, the application of waste heat recovery (WHR) technology to the HD diesel engine has proven to be challenging due to cost, complexity, packaging and control during transient operation. This paper discusses the methods and technical innovations required to achieve reliable high performance operation of the WHR system. The control techniques for maintaining optimum energy recovery while protecting the system components and working fluid are described. The experimental results are presented and demonstrate that 3-5% fuel saving is achievable by utilizing this technology.

Waste heat recovery (WHR) has been recognized as a promising technology to achieve the fuel economy and green house gas reduction goals for future heavy-duty (HD) truck diesel engines. A Rankine cycle system with ethanol as the working fluid was developed at AVL Powertrain Engineering, Inc. to investigate the fuel economy benefit from recovering waste heat from a 10.8L HD truck diesel engine. Thermodynamic analysis on this WHR system demonstrated that 5% fuel saving could be achievable. The fuel economy benefit can be further improved by optimizing the design of the WHR system components and through better utilization of the available engine waste heat. Although the WHR system was designed for a stand-alone system for the laboratory testing, all the heat exchangers were sized such that their heat transfer areas are equivalent to compact heat exchangers suitable for installation on a HD truck diesel engine.

Despite the best preventative measures, ruptured hoses, spills and leaks do occur with the use of all hydraulic equipment. Although these releases do not usually produce an RCRA (Resource Conservation and Recovery Act) regulated waste, they are often reportable events. Clean-up and subsequent administrative procedures involve additional costs, labor, and work delays. Concerns about these releases, especially when they involve Sandia National Laboratories, New Mexico (SNL) vehicles hauling waste on public roads, prompted their Fleet Services Department (FS) to seek an alternative to conventional petroleum-based hydraulic fluids. Since 1996, SNL has participated in a pilot program, along with the University of Northern Iowa (UNI) Ag-Based Industrial Lubricants (ABIL) Research Program and selected vehicle manufacturers, to field test in twenty of its vehicles, hydraulic fluid produced from soybean oil.

Future fuels for internal-combustion engines will be derived increasingly from solids such as coal. An alternative to processing coal into liquid fuels is the direct use of solid coal by reciprocating, internal -combustion engines. Specific applications which would be especially suitable for solid fueled engines consist of stationary power plants, marine propulsion systems, and railroad locomotives. Agricultural, construction and mining equipment are examples of other possible applications. The objectives of this study were to review past research on the development of solid coal fueled engines and, from this review, to identify major technical problems and current research needs. The objectives also included comparing the energy usage of several fuels. This comparison indicated a possible 25% energy advantage by directly using solid coal fuels as opposed to using synfuels.

For over a decade engine manufacturers have been pursuing alternative fuel strategies for vehicle powertrains. First came the discussion of fuel selection. Next, whether or not these alternative fuels can provide the utility offered by traditional diesel. Finally, the footrace of technology and hardware to provide utility, reliability and maintainability with the use of alternative fuels. Now the day has come where many alternative fuels are a practical reality. The body of this paper will discuss the utilization of natural gas as an alternative fuel. This paper targets the fleet operator in an effort to provide a single source of information in a concise format. A discussion of emission standards, engine operational strategies, component technology, fuel characteristics and the utility of using natural gas as a fuel will be addressed. The understanding of present and future engine development is of great importance to a successful fleet operation.