Current Issue : October - December Volume : 2016 Issue Number : 4 Articles : 5 Articles
A total of 10,561 all-terrain vehicle (ATV) related deaths have been documented for the\nyears 1985 through 2009 in the United States, most of which were associated with overturns of the\nmachine. The current analysis addresses the question, ââ?¬Å?How effective is the QuadbarTM (QB) as\na crush prevention device (CPD) in preventing ATV overturn-related injuries?ââ?¬Â A CPD is designed\nas a guard against crushing injuries to the ATV rider in the event of an overturn. The analysis used\na prevention effectiveness model to address this question. Based on this analysis, the CPD and more\nspecifically the QB were found to potentially prevent serious injuries and death to ATV riders that\nresult from overturns. Systematic real-life studies are needed to evaluate the prevention potential\nof CPDs that are in use to guide the implementation of policies to better protect the public from\nthese injuries....
Vehicles as transportation are popular and mainly use among peoples around the\nworld for various kind of purpose either personal or not. Over hundreds of year internal\ncombustion engines widely used because of high efficiency and low maintenance compare to\nnew technology which are using cells of battery. Nevertheless, emission cause of incomplete\ncombustion such engine misfire normally occurs as well. For instances, some mechanical,\nsensors or actuators failure and environmental condition contribute to the engine misfire. The\nimportance of engine misfire detection (EMD) is to ensure engine emissions not harmful to the\nenvironments and avoid damage of catalytic converter. By using low cost narrowband oxygen\nsensor to acquire air to fuel ratio (AFR) signal behavior under misfire condition and analyst by\ndigital signal processing method using Discrete Fourier Transform (DFT) algorithm for Digital\nButterworth Filter designation is discussed in this paper....
Acoustic emission (AE) technique has recently been extensively used in machine health monitoring and\ndiagnosis of diesel engine. Although it offers many advantages for early detection of fault symptoms, it also comes\nwith many challenging problems. Due to its operation in high frequency range (stress waves), from a few kHz to MHz,\nit poses a problem of massive data storage and transmission. Furthermore, the non-linearity of AE sensors is also\nanother challenge as it does not provide any quantitative/comparative analysis if multiple sensors are used, such\nin multi-cylinder diesel engine. Hence, this short paper will present the work carried out in the author�s laboratory\nby introducing a simple and innovative data reduction process termed as Peak Hold down Sampling (PHDS) and a\nnormalization approach for diagnosis of diesel engine....
The increasing global environmental awareness, evidenced by recent worldwide calls for control of\nclimate change and greenhouse emissions, has placed significant new technical mandates for automotives to\nimprove engine efficiency, which is directly related to the production of carbon dioxide, a major greenhouse gas.\nReduction of parasitic losses of the vehicle, powertrain and the engine systems is a key component of energy\nconservation. For engine efficiency improvement, various approaches include improvements in advanced combustion\nsystems, component system design and handlingââ?¬â?such as down-sizing, boosting, and electrificationââ?¬â?as\nwell as waste heat recovery systems etc. Among these approaches, engine friction reduction is a key and\nrelatively cost-effective approach, which has been receiving significant attention from tribologists and\nlubricant-lubrication engineers alike. In this paper, the fundamentals of friction specific to the environments of\nengine components tribology are reviewed, together with discussions on the impact of developing vehicle\npowertrain technologies, surface and material technologies, as well as lubricant and additive technologies on\npromises of continuing friction and wear reduction trends. The international accords on climate change require\nfurther gains in fuel efficiency and energy sustainability from all industry sectors including those in the\nautomotive and the broader internal combustion engine industries, and the latter encompass off-highway,\npower generation, marine, and rail industries as well. This paper focsuses on friction reduction in mainly\nautomotive engines, however.\nThe paper starts with a clarification of the common descriptors of mechanical losses and friction in the\nengine, followed by the topic of lubrication fundamentals such as lubrication regimes. Then the lubrication of\nthe contacting surfaces in each of the major engine subsystems is discussed in turn. These subsystems include\nthe piston assembly: ring-pack/liner, piston-skirt/liner, and piston-pin/connecting-rod contacts; connecting rod\nand crankshaft bearings; and the valvetrain subsystem. The relative contributions to total friction from the\nvarious subsystems are discussed, with the piston-assembly contributing to about half of the total friction. The\nremainder of the friction comes from the crankshaft, connecting rod, camshaft bearings, and the valvetrain\noscillating parts. The bearings are in predominantly hydrodynamic lubrication, in contrast to the valvetrain\noscillating components, which are characterized to be mostly in the mixed/boundary lubrication regimes.\nDespite the title of the paper, a section on emerging powertrain technologiesââ?¬â?including that of combustion\nin gasoline and diesel enginesââ?¬â?is also given in the context of the trend towards clean and efficient propulsion\nsystems. The impact of these developing technologies on the reduction of friction and parasitic losses via\ncomponent, material, and lubricant deisgn will be discussed. These technologies include gasoline direct injection\n(GDI), turbocharged, and hybrid vehicles and will generate unique green environmental opportunities for\nfuture propulsion systems. These technologies are critical to meet fuel economy and reduced emission targets.\nSpecifically, this paper will address the impact of these emerging technologies on future lubricant requirements\nand advanced tribology research. The connection between these lubricant and tribological requirements will be illustrated by briefly describing the basic lubrication and friction processes at the major engine components\nincorporating the emerging technologies.\nLastly, besides new hardware and material science changes, several advanced additives such as advanced\nfriction modifiers, antiwear additive chemistries, low viscosity lubricants, and the introduction of new VI\nImprovers all represent possible tribological solutions to the challenge of meeting more stringent energy\nefficiency requirements and environmental legislation. As original equipment manufacturers (OEMs) seek to\naccomplish these goals, hardware and emission system changes will place new demands and even greater\nstress on engine oils. At the same time, engine durability, performance and reliability are of primary importance\nto vehicle owners and operators. The final section of this paper will discuss the future trends of engine friction\nreduction and wear control by surface modification such as friction-reducing coatings or surface textures in\nengine components. The impact of surface coatings or surface textures on engine friction will be reviewed.\nIn addition, the OEMs and lubricant formulation manufacturers will need to respond with novel engine oil\ntechnologies formulated to protect the engine, keeping the emissions system working at the optimal fuel\neconomy, while retaining engine durability.\nIn brief, the paper (i) reviews the characteristics of component friction in the environment of the internal\ncombustion engine and the relevant design considerations, (ii) addresses the impact of emerging technologies\non engine friction and the tribological changes and requirements, especially on lubricant and additives, and\nlastly (iii) discusses the interactions between lubricant-additive formulations and material surface engineering,\nand their effects on friction, wear and engine durability. The increasing importance and interplay between\nsynergistic advancements in component design, material and surface engineering, and advanced lubricant-additive\nformulation will be fully illustrated....
This paper presents a set of parametric studies of heat dissipation performed on automotive radiators.\nThe work�s first step consists of designing five radiators with different fin pitch wave distance\n(P = 2.5, 2.4, 2.3, 2.2, 2.1 mm). Then, we proceed to the fabrication of our five samples. The\npurpose of this work is to determine through our experiment�s results which one have the best\ncooling performance. This numerical tool has been previously verified and validated using a wide\nexperimental data bank. The analysis focuses on the cooling performance for automobile radiator\nby changing several dimensions of the radiator fin phase as well as the importance of coolant flow\nlay-out on the radiator global performance. This experience has been performed at Hubei Radiatech\nAuto Cooling System Co., Ltd. For the cooling performance experience, we use JB2293-1978\nWind Tunnel Test Method for Automobile and Tractor Radiators. The test bench system is a continuous\nair suction type wind tunnel; collection and control of operating condition parameters can\nbe done automatically by the computer via the preset program, and also can be done by the user\nmanually. The results show that the more we increase the fin phase, the better the cooling performance\nwill be and we also save material so the product cost will be cheaper....
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