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This paper presents some of the history of the Spacemetal process development; a discussion of the core forming machine, a description of the welder where corrugated core and facing sheets are joined; the quality control process employed for inspecting the finished product; and some of the material properties and applications. FOREWORD Development of a production process and the machines for fabrication of a resistance welded steel sandwich was made by Missile Division, North American Aviation, Inc. Development was carried forward under contract AF 33(600)-26154 from the Manufacturing Methods Branch, Industrial Resources Division of the Air Materiel Command USAF.

Biofuel can enable a sustainable transport solution and lower greenhouse gas emissions compared to standard fuels. This study focuses on biodiesel, implemented in the easiest way as drop in fuel. When mixing biodiesel into diesel one can run into problems with solubility causing contaminants precipitating out as insolubilities. These insolubilities, also called soft particles, can cause problems such as internal injector deposits and nozzle fouling. One way to overcome the problem of soft particles is by filtration. It is thus of great interest to be able to quantify fuel filters’ ability to intercept soft particles. The aim of this study is to test different fuel filters for heavy-duty engines and their ability to filter out synthetic soft particles. A custom-built fuel filter rig is presented, together with some of its general design requirements. For evaluation of the efficiency of the filters, fuel samples were taken before and after the filters.

A method for the analysis of a damaged bearing is described. An emphasis is placed on obtaining complete and accurate application information; conducting a thorough visual examination; making physical measurements as necessary; and conducting metallurgical tests. The method has been used for tapered roller bearings as well as a variety of other components of various steel types and processing histories.

A combustion system has been developed to burn neat (pure) methanol in a direct-injection four-stroke-cycle engine. Primary objectives were to obtain low fuel consumption and long component life to make the engine suitable to replace heavy-duty diesel fueled engines. A glow plug was placed in a modified quiescent combustion chamber to ensure reliable methanol ignition at all engine operating conditions. The methanol engine provides thermal efficiency nearly equal to the diesel engine from which it is derived, in addition, nitrogen oxide emissions are reduced by 50 percent and exhaust smoke is negligible. Hydrocarbon emissions are still above the baseline diesel engine. Laboratory and field durability tests of over 2000 hours have been completed. Excellent cold-start capability has been established.

The internal combustion engines emit combustion gases which contain nano and micrometric particles that are harmful to human health, causing deleterious damages to the human's respiratory system. In Brazil, heavy vehicles, such as buses and trucks, have diesel engines that work under high loads and run through metropolitan areas or in intense traffic flow roads. They are considered, nowadays, the main solid particles emitter in several World's areas. There are already standard systems to analyze these particles quantitative and qualitatively at high prices collected from vehicle gases emissions in places such as bus stops. This paper presents a new method which retains solid micrometric particulate matter emitted by diesel engine. It is simple and has a relatively low cost. A sheet of textile element was encapsulated in a system for gripping micrometric particles emitted by diesel single-cylinder engine operating in a bench and coupled with a electrical generator.

The titanium alloy system offers a range of properties conducive to weight/space savings. These properties include high strength, low elastic modulus and low density, which uniquely suit them for spring applications. By utilizing titanium in various spring designs, suspension engineers can save up to 60% of the weight and 20-30% of the space for a comparable steel spring. The primary impediment to widespread titanium part production and use in the past was cost. A new low cost titanium alloy system designed specifically for suspension and drive train application has been tested and proved to limit this cost problem. Working with titanium in their suspension designs, engineers will save significant weight/space over comparable steel and aluminum components.

Developed to cut down on maintenance costs and increase the earning power of the vehicle, this family of suspensions provides for improved vehicular behavior - items such as stability, braking, cornering, and overall ride. The suspensions utilize a principle of providing a cushioned variable rate ride through the use of molded rubber springs. Floating walking beams distribute weight equally on both axles in the case of tandems. The axles are positively located by upper wishbones and lower torque rods. The parallelogram thus formed prevents windup and axle hop. The correct use of metals shows a substantial weight saving in the entire model range.

For the purpose of developing direct injection heavy-duty methanol engines which surpass diesel engines in purformace, this paper first clarifies the methanol concentration around the spark plug for achieving a high ignition stability by sampling the gas near the spark plug using a sampling valve. The combustion process of methanol is then observed by the method of high-speed Schlieren photography to clarify the mode of methanol combustion. A new methanol DISC combustion system having a protrusion in the combustion chamber is devised based on such results. This study clarifies that the methanol concentration at the point of ignition for high ignition stability is in the range of 6 to 22 vol%. The methanol mixture burns by flame propagation so far as the compression ratio is on the order of 16.5.

A new concept in conventional truck cab vibration isolation has been developed by Holland Neway International. The system provides a significant improvement in ride comfort for the truck cab occupants in the truck of the twenty-first century. The single point isolator incorporates inclined sleeve type air springs to achieve a very low natural frequency, typically 0.9 - 1.1 hertz. A unique variable geometry damping system is used in conjunction with the sleeve springs to allow the configuration to achieve significant improvements in vibration isolation. The passive variable geometry control operates essentially undamped until large displacement disturbances are encountered allowing maximum possible isolation performance. Since the isolator natural frequency occurs in a region where the human physiology is most tolerant of vibratory motion, a high level of ride comfort is achieved.

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.

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.

Presenting a brand new approach to heat exchangers for engines, transmissions, hydraulic systems, etc. This new heat exchanger is made of only two pieces of circular extruded aluminum profiles: Core and shell. No soldering: The core and the shell is assembled by a minimum of automated work. In an oil to water cooling application, the active surface on the oil side of the core is enlarged by fins 0.2 mm thick, 0.3 mm spacing, and 3 mm high. The fins are made in unique production machines and enlarge the active surface area approximately five times compared to a conventional heat exchanger of the same dimensions. The principle utilizes the low pressure drop at laminar flow and avoids the disadvantage of low heat transfer after a certain laminar flow length. The result is approximately three times higher oil heat dissipation, combined with very low oil pressure drop, compared to conventional technique.

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.

A farm tractor protection cab made of thin steel sheet pressings is described. The cab is designed and produced using entirely automotive-type procedures. Curved glasses and a dampening suspension of the glasses are found to be an important means of achieving a low noise level in the cab. Using the pressing technique when producing a steel cab makes it possible to give the various cab details rigidity with a minimum of material. When welded together, these details form a very stiff cab body, which gives the necessary mechanical strength. The curved surfaces, the radii, and the round forms, which from a tooling point of view are natural for pressed steel parts, also have a vibration-dampening effect on the entire cab construction, thus making it easier to design a quiet tractor cab. Mounted on a farm tractor of conventional design, the cab meets the noise rating number ISO N85.

Today’s growing commercial vehicle population creates a demand for fossil fuel surplus requirement and develops highly polluted urban cities in the world. Hence addressing both factors is very much essential. Battery electric vehicles are with limited vehicle range and higher charging time. So it is not suitable for the long-haul application. In further the hydrogen fuel cell-based electric vehicles are the future of the commercial electric vehicle to achieve long-range, zero-emission and alternate for reducing fossil fuels requirement. The hydrogen fuel cell electric vehicle range, it means the total distance covered by the vehicle in a single filling of hydrogen into the onboard cylinders. And here the prediction of the vehicle range is essential based on optimal parameters; vehicle acceleration, speed, trip time etc. before the start of the trip.

Abstract Due to the incoming phase out of fossil fuels from the market in order to reduce the carbon footprint of the automotive sector, hydrogen-fueled engines are candidate mid-term solution. Thanks to its properties, hydrogen promotes flames that poorly suffer from the quenching effects toward the engine walls. Thus, emphasis must be posed on the heat-up of the oil layer that wets the cylinder liner in hydrogen-fueled engines. It is known that motor oils are complex mixtures of a number of mainly heavy hydrocarbons (HCs); however, their composition is not known a priori. Simulation tools that can support the early development steps of those engines must be provided with oil composition and properties at operation-like conditions. The authors propose a statistical inference-based optimization approach for identifying oil surrogate multicomponent mixtures. The algorithm is implemented in Python and relies on the Bayesian optimization technique.

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.

Recent research on carburized steels has demonstrated a correlation between the toughness properties of a carburized steel and the fatigue performance in combined load testing (high-cycle fatigue plus overload). The data presented suggest that, for applications where loads above the fatigue limit are encountered, both processing and alloying must be considered. Results from a number of investigations are reviewed to illustrate that high-cycle fatigue properties are controlled primarily by the processing, whereas toughness characteristics, such as resistance to random cyclic loading, are a result of the alloying.

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.