The Stiller-Smith mechanism is a new mechanism for the translation of linear motion into rotary motion, and has been considered as an alternative to the conventional slider-crank mechanism in the design of internal combustion engines and piston compressors. Piston motion differs between the two mechanisms, being perfectly sinusoidal for the Stiller-Smith case. Plots of dimensionless volume and volume rate change are presented for one engine cycle. It is argued that the different motion is important when considering rate-based processes such as heat transfer to a cylinder wall and chemical kinetics during combustion. This paper also addresses the fact that a Stiller-Smith engine will be easier to configure for adiabatic operation, with many attendant benefits.
On-board emissions measurement for heavy-duty vehicles has taken on greater significance because new standards now address in-use emissions levels in the USA. Emissions compliance must be shown in a Motto-exceed (NTE) zone that excludes engine operation at low power. An over-the-road 1996 Peterbilt tractor was instrumented with the West Virginia University Mobile Emissions Measurement System (MEMS). The researchers determined how often the truck entered the NTE, and the emissions from the vehicle, as it was driven over different routes and at different test weights (20,740 Ib, 34,640 Ib, 61,520 Ib, and 79,700 lb) The MEMS interfaced with the truck ECU, while also measuring exhaust flowrate, and concentrations of carbon dioxide (CO 2 ) and oxides of nitrogen (NOx) in the exhaust. The four test routes that were employed included varying terrain types in order to simulate a wide range of on-road driving conditions. One route (called the Bruceton route) included a sustained hill climb. Another route (known as the Saltwell route) traversed more rolling hills throughout the duration of the test. For 34,640 lb and 79,700 lb, the vehicle was tested on a route that was a reasonably flat road (PA 43 route), and a route through city traffic (Stop-n-go). As an example of results from the study, on the Bruceton route at 20,740 lb, the truck spent only 8.24% of the time within the NTE, but at 80,000lb on the same route it spent 35.67% of test duration in the NTE. Distance-specific NOx and fuel consumption were typically 50 to 80% higher in the NTE zone than over the whole route.
A linear engine/alternator was simulated and designed, and a prototype was built at West Virginia University. This paper describes the engine and presents original operational data. The linear engine was a two-cylinder, two-stroke, common rail direct injection, compression ignition engine. The engine was built using off the shelf components to reduce cost where it was possible. Engine control, injection duration and timing, were achieved using a microcontroller with piston position as a control input. Experiments on the engine were performed to study its behavior. The studied variables included mass of the translator, amount of fuel injected, injection timing, load, and stroke with operating frequency and mechanical efficiency as the basis of comparison. At this point of development, the engine was far from optimized; however, the trends in engine behavior were clear. Increasing the translator mass resulted in decreased operating frequency. Increasing the stroke length also resulted in decreased operating frequency. Overcharging and increased fueling rate, both, resulted in increased power output, efficiency, and operating frequency. Advancing injection timing resulted in increased frequency, efficiency and power output, and decreased stalling frequency. This suggests that the engine operated in an HCCI-like fashion.
Abstract Results from a study directed towards identifying and measuring the mutagenicity of diesel exhaust particulate matter involved in mining exposures, especially those which may synergistically affect genotoxic hazard, are presented in this paper. Particulate matter emissions from a diesel engine, representative of the ones found in underground mines, were sampled and assayed to determine the genotoxic potential as a function of engine operating conditions. Diesel exhaust was diluted in a multi‐tube mini‐dilution tunnel and the particulate matter was collected on 70 mm fluorocarbon coated glass fiber filters as well as on 8” × 10” hi‐volume filters. A six node steady state duty cycle was used to relate engine operating conditions to the mutagenicity potential. Protocols developed for using a primary component of pulmonary surfactant as a medium for collecting and applying respirable particulate material to cells for mutagenicity testing offer a true representation of in‐vivo delivery of such respired aerosols to pulmonary cells and the genetic material within. The surfactant dispersion technique is discussed in this paper. Methods have been developed to sample and assay the diesel soot and diesel soot/mineral dust complexes which would not compromise the surface and physical properties of the particulate material.
A method exists to predict heavy-duty vehicle fuel economy and emissions over an "unseen" cycle or during unseen on-road activity on the basis of fuel consumption and emissions data from measured chassis dynamometer test cycles and properties (statistical parameters) of those cycles. No regression is required for the method, which relies solely on the linear association of vehicle performance with cycle properties. This method has been advanced and examined using previously published heavy-duty truck data gathered using the West Virginia University heavy-duty chassis dynamometer with the trucks exercised over limited test cycles. In this study, data were available from a Washington Metropolitan Area Transit Authority emission testing program conducted in 2006. Chassis dynamometer data from two conventional diesel buses, two compressed natural gas buses, and one hybrid diesel bus were evaluated using an expanded driving cycle set of 16 or 17 different driving cycles. Cycle properties and vehicle fuel consumption measurements from three baseline cycles were selected to generate a linear model and then to predict unseen fuel consumption over the remaining 13 or 14 cycles. Average velocity, average positive acceleration, and number of stops per distance were found to be the desired cycle properties for use in the model. The methodology allowed for the prediction of fuel consumption with an average error of 8.5% from vehicles operating on a diverse set of chassis dynamometer cycles on the basis of relatively few experimental measurements. It was found that the data used for prediction should be acquired from a set that must include an idle cycle along with a relatively slow transient cycle and a relatively high speed cycle. The method was also applied to oxides of nitrogen prediction and was found to have less predictive capability than for fuel consumption with an average error of 20.4%.
As mixed-reality (XR) technology becomes more available, virtually simulated training scenarios have shown great potential in enhancing training effectiveness. Realistic virtual representation plays a crucial role in creating immersive experiences that closely mimic real-world scenarios. With reference to previous methodological developments in the creation of information-rich digital reconstructions, this paper proposes a framework encompassing key components of the 3D scanning pipeline. While 3D scanning techniques have advanced significantly, several challenges persist in the field. These challenges include data acquisition, noise reduction, mesh and texture optimisation, and separation of components for independent interaction. These complexities necessitate the search for an optimised framework that addresses these challenges and provides practical solutions for creating realistic virtual representations in immersive training environments. The following exploration acknowledges and addresses challenges presented by the photogrammetry and laser-scanning pipeline, seeking to prepare scanned assets for real-time virtual simulation in a games-engine. This methodology employs both a camera and handheld laser-scanner for accurate data acquisition. Reality Capture is used to combine the geometric data and surface detail of the equipment. To clean the scanned asset, Blender is used for mesh retopology and reprojection of scanned textures, and attention given to correct lighting details and normal mapping, thus preparing the equipment to be interacted with by Virtual Reality (VR) users within Unreal Engine. By combining these elements, the proposed framework enables realistic representation of industrial equipment for the creation of training scenarios that closely resemble real-world contexts
Heavy-duty trucks account for a substantial portion of the atmospheric carbon dioxide (CO2) and nitrogen oxides (NOx) inventory. The data presented in this paper will help the research community be interested in developing models that predict the NOx and CO2 levels in real use. Continuous data of emissions were recorded from chassis dynamometer testing of five 2003-2005 model year (MY) heavy-duty trucks. The instantaneous emissions rate was plotted against axle power in all cases. The effect of vehicle test weight and the drive cycle employed on the relation between emissions rate (grams per sec) and axle power was studied. The NOx/CO2 ratio was found to be independent of the test cycle. The average NOx/CO2 ratio for the 2003-2005 MY trucks was found to be 0.0051, which agrees reasonably well with the estimated ratio of 0.0048, based on certification standards. The data were compared to those from 1994-2002 MY trucks; the average NOx/CO2 ratio for those trucks was 0.0141. For the 2003-2005 MY trucks, the distance specific NOx (grams per mile) and the fuel economy (miles per gallon) were less than those of 1994-2002 MY trucks.
Drawing on the work of Andrew Feenberg, Gilbert Simondon, Yuk Hui, Mary Helms and others, we develop a critical account of human 'technics'—understood broadly as the 'bringing forth' of the properties and potentialities of physical reality—as an enfolding of planetary and cosmic powers into the social world. We use the contemporary examples of synthetic chemicals and mineral extraction to explore how such a framing illuminates the dangers of modern technology in a new way. We then turn to the longer history of magico-mythical and ritualised ways in which human involvement in potentially dangerous technical activities has been understood and regulated. In the final section, we step back and consider the prospects for a new, 'spiritualised' or cosmological reimagining of technology in the contemporary world that draws on the insights of both western science and a-modern knowledge formations.
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