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Advanced Vehicle Technologies (AVT), a Ballarat Australia based company, has developed the World's first diesel to 100% LPG conversion for heavy haul trucks. There is no diesel required or utilized on the trucks. The engine is converted with minimal changes into a spark ignition engine with equivalent power and torque of the diesel. The patented technology is now deployed in 2 Mercedes Actros trucks. The power output in engine dynamometer testing exceeds that of the diesel (in excess of 370 kW power and 2700 Nm torque). In on-road application the power curve is matched to the diesel specifications to avoid potential downstream power-train stress. Testing at the Department of Transport Energy & Infrastructure, Regency Park, SA have shown the Euro 3 truck converted to LPG is between Euro 4 and Euro 5 NOx levels, CO2 levels 10% better than diesel on DT80 test and about even with diesel on CUEDC tests.

The demand for improved fuel economy in both cars and trucks has emphasized the need for lighter weight components. The application of high strength steel to wheels, both rim and disc, represents a significant opportunity for the automotive industry. This paper discusses the Ranger HSLA wheel program that achieved a 9.7 lbs. per vehicle weight savings relative to a plain carbon steel wheel of the same design. It describes the Ranger wheel specifications, the material selection, the metallurgical considerations of applying HSLA to wheels, and HSLA arc and flash butt welding. The Ranger wheel design and the development of the manufacturing process is discussed, including design modifications to accommodate the lighter gage. The results demonstrate that wheels can be successfully manufactured from low sulfur 60XK HSLA steel in a conventional high volume process (stamped disc and rolled rim) to meet all wheel performance requirements and achieve a significant weight reduction.

The in-cylinder direct injection of fuels can be a further step towards cleaner and more efficient internal combustion engines. However, the injector design and its characterization, both experimental and from numerical simulation require accurate diagnostics and efficient models. This work aims to simulate the complex behavior of the gaseous and liquid jets through an outwardly opening injector characterized by optical diagnostics using a one-dimensional model without using three dimensional models. The behavior of the jet from an outwardly opening injector changes according to the type of fuel. In the case of the gas, the experimental investigations put in evidence three main jet regions: 1) near-field region where the jet shows a complex gas-dynamic structure; 2) transition region characterized by intense mixing; 3) far-field region characterized by a fully developed subsonic turbulent jet.

This paper describes the after-treatment technology that could be used to meet a future BS-VII standard, considering close-coupled SCR (cc-SCR) to help start NOx conversion earlier. Both active (Cu/Fe-SCR based) and passive (V-SCR based) systems have the potential to meet emission limits. V-SCR may be considered in the rear position because V-SCR shows a fast response with very low N2O formation. Next-gen V-SCR technology shows significantly improved performance and durability closer to Cu-SCR. The steady-state NOx conversions over Next-Gen V-SCR were better than BS-VI V-SCR in both fresh and aged-580°C/100h conditions. High durability was also observed after engine aging of 1000h (WHTC + high load). Another big challenge in BS VII could be the PN10 requirement. With enhanced filtration coating (EFC) technology, PN emissions drop drastically in comparison to Euro VI reference without EFC to meet a future BS VII.

Manufacturers of heavy-duty diesel engines are facing increasingly stringent, emission standards. These standards have motivated new research efforts towards improving the performance of diesel engines. The objective of the present program is to develop a comprehensive analytical model of the diesel combustion process that can be used to explore the influence of design changes. This will enable industry to predict the effect of these changes on engine performance and emissions. A major benefit of the successful implementation of such models is that engine development time and costs would be reduced through their use. The computer model is based on the three-dimensional KIVA-II code, with state-of-the-art submodels for spray atomization, drop breakup / coalescence, multi-component fuel vaporization, spray/wall interaction, ignition and combustion, wall heat transfer, unburned HC and NOx formation, and soot and radiation.

Health related problems in over populated areas are a major concern and as such, there are specific legislations for noise generated by transport vehicles. In diesel powered commercial vehicles, the source for noise are mainly related to rolling, transmission, aerodynamics and engine. Considering internal combustion engine, three factors can be highlighted as major noise source: combustion, mechanical and tailpipe. The tailpipe noise is considered as the noise radiated from the open terminations of intake and exhaust systems, caused by both pressure pulses propagating to the open ends of the duct systems, and by vortex shedding as the burst leaves the tailpipe (flow generated noise). In order to reduce noise generated by vehicles, it is important to investigate the gas interactions and what can be improved in exhaust line design during the product development phase.

The paper investigates the interaction between soil and tractor tires through a 2D numerical model. The tire is schematized as a rigid ring presenting a series of rigid tread bars on the external circumference. The outer profile of the tire is divided into a series of elements, each one able to exchange a normal and a tangential contact force with the ground. A 2D soil model was developed to compute the forces at the ground-tire interface: the normal force is determined on the basis of the compression of the soil generated by the sinking of the tire. The soil is modeled through a layer of springs characterized by two different stiffness for the loading (lower stiffness) and unloading (higher stiffness) condition. This scheme allows to introduce a memory effect on the soil which results stiffer and keeps a residual sinking after the passage of the tire. The normal contact force determines the maximum value of tangential force provided before the soil fails.

A pin and disc machine has been modified for the evaluation of silver-steel lubrication characteristics of railroad diesel oils. Use of silver pins on polished steel discs at selected loads and rubbing speeds allows good correlation with known engine behavior. In comparison with wear and friction data obtained by the four ball method, this pin and disc test gives better correlation with engine tests than the Modified Four Ball Test.

The Standard Multipass (Beta) Filter Method (ISO 4572) has been a highly recognized and widely accepted test throughout industry since its introduction in the early 1970's. In the past decade, the Beta Method has indeed made a major contribution in assisting users in selecting filters to meet system design requirements. However, many complaints have been voiced by users that filters normally produce a lower particle removal efficiency under field applications than they do during laboratory tests. Research results from work carried out at the Fluid Power Research Center at Oklahoma State University indicate that the degradation of the filtration (Beta) ratio in service depends mainly on the filter's retentivity characteristic. This paper highlights the theoretical basis of the Epsilon Rating Method and the concept of retentivity. Most important, the paper uses these concepts to correlate filter performance between laboratory tests and field operation.

Engine mounts are an integral part of the vehicle that helps in reducing the vibrations generated from the engine. Engine mounts require a simple yet complicated amalgamation of two very different materials, steel and rubber. Proper adhesion between the two is required to prevent any part failure. Therefore, it becomes important that a comprehensive study is done to understand the mating phenomenon of both. A good linking between rubber and metal substrate is governed by surface pretreatment. Various methodologies such as mechanical and chemical are adopted for the same. This paper aims to present a comparative study as to which surface pretreatment has an edge over other techniques in terms of separation force required to break the bonding between the two parts. The study also presents a cost comparison between the techniques so that the best possible technique can be put to use in the commercial vehicle industry.

This paper describes the results of a series of fatigue studies relating the lives of several weld geometries. Rotating beam and axially loaded specimens were used. A comparison between steel and plastic (polyvinylchloride scale models is made. Using plastic scale models of welded structures for fatigue life determination is the ultimate goal of this work.

“Today, wearing parts are regularly subjected to abnormal loading conditions. They must be able to accept these conditions without failure. In continuous operations, unscheduled downtime greatly increases maintenance costs, not to mention the cost of lost production. White iron castings offer premium abrasion resistance for many of these applications, but are often not used due to the possibility of brittle failure and the difficulty of mechanical attachment. This paper discusses the properties and applications of a composite of martensitic white iron and mild steel. This laminate will accept medium to high impact without loss of service failure, and can be installed by mechanical means or with welded attachment.”

Euro 6 emission norms are getting implemented in India from April 2020 and it is being viewed as one of the greatest challenges ever faced by the Indian automotive industry. In order to achieve such stringent emission norms along with top performance for vehicle, a good strategy should be incorporated to control system out NOx emissions and soot regeneration. Extruded Vanadium catalyst is deployed for this passive regeneration system with DOC (Diesel Oxidation Catalyst), DPF (Diesel Particulate Filter) and SCR (Selective Catalyst Reduction), where the amount of catalyst loading in DOC plays an apex role in deciding conversion efficiency of SCR and passive regeneration capabilities. This study mainly focuses on the impact of catalyst loading of DOC over SCR efficiency. NO2 to NOx ratio should be close to 0.5 for optimum conversion efficiency of SCR. Catalyst loading in DOC decides the amount of NO2 coming upstream to SCR.

Emissions and in-cylinder pressure traces are used to compare the relative importance of soot formation and soot oxidation in a heavy-duty diesel engine. The equivalence ratio at the lift-off length is estimated with an empirical correlation and an idealized model of diesel spray. No correlation is found between the equivalence ratio at lift-off and the soot emissions. This confirms that trends in soot emissions cannot be directly understood by the soot formation process. The coupling between soot emission levels and late heat release after end of injection is also studied. A regression model describing soot emissions as function of global engine parameters influencing soot oxidation is proposed. Overall, the results of this analysis indicate that soot emissions can be understood in terms of the efficiency of the oxidation process.

Current trends in environmental and emissions regulations are driving changes in new engine systems, and increasing the need for more effectively sealed joints in exhaust systems. At the high temperatures in these exhaust systems it is difficult for traditional gaskets to provide an effective seal, as they degrade at high operating temperatures. This paper introduces a coating that has both excellent temperature stability and good compliance, thus forming an excellent sealing enhancement for metallic layers in exhaust system gaskets. Temperature stability data is presented along with sealing data, which illustrate the superior performance of this material compared to current systems.

Heavy-duty diesel engines for transit bus applications are having to meet increasingly stringent emission standards. The new engines are significantly cleaner than they were just a few years ago. However, due to the long life of transit buses in Ontario (18 years), many buses still in service are powered by older engines which produce greater amounts of regulated exhaust emissions. The Ottawa-Carleton Regional Transit Commission (OC Transpo) has an interest in reducing emissions from older transit buses in their fleet. Eight Donaldson particulate trap systems were installed on transit buses. The purpose of the work, involving four different bus/engine combinations, was to assess the practicality and benefits of particulate traps in transit applications. This paper discusses the demonstration of diesel exhaust particulate traps in Ottawa-based transit buses.

A software tool has been developed to aid designers and process engineers in the development and improvement of heat treat processes. This tool, DANTE™, combines metallurgical phase transformation models with mass diffusion, thermal and mechanical models to simulate the heating, carburization, quenching and tempering of steel parts. The technology behind the DANTE software and some applications are presented in this paper.

Paper describes analysis of the design process of modern automotive LPG and CNG containers. Over decade experience in the field of both computer based analysis as well as in the real conditions testing has been collected and presented in the paper. Authors present the potentials of modern FEM methodologies in the optimization and production of lightweight steel containers. It has been proved that the most sophisticated numerical analysis have to be followed by the construction verification, particularly considering direct exposure to fire. Bonfire test have become obligatory for both liquid and compressed gases containers. Properly chosen fire protection system, together with the adequate level of quality of materials applied for its production together with proper directing of the gas flowing out from safety devices are the essential factors defining gas containers fire safety.

Diesel powered vehicles are characterized by two distinctives, of particulate, sensed by sight, and odor, sensed by smell. Dramatically reducing these distinctives would result in a “clean diesel”. A joint program of Yellow Freight System, Inc. (YFS) and the author's employer (DCI) has addressed one distinctive (particulate) and has resulted in an exhaust filtering system for the diesel forklift trucks YFS use to move freight at their terminals. This paper covers design, installation, and testing of the system to filter the particulate emissions emanating from these forklifts. The filters, designed to operate for one programmed maintenance (PM) cycle, are then cleaned in off-board equipment and returned to service for another cycle. All filter materials utilized are compatible with the 200°C normal maximum operating temperature, although short excursions to 260°C have not been detrimental.

The authors used a mass spectrometer to determine an SOF reduction mechanism of a diesel oxidation catalyst. The results indicate that SOF reduction lies in the catalytic conversion of high molecular organic matter to low molecular organic matter. And unregulated emissions are also reduced through this conversion. It is also found that the SOF reduction performance is highly dependent up on the condition of the wash coat. There is some limitation to improving diesel oxidation catalyst performance because of the sulfur content found in diesel fuel. Finally, the authors have determined what we think are the specifications of the presently best catalytic converter.