Installation and testing of a Cummins QSK19 lean burn natural gas engine

2013 Spring.Includes bibliographical references.The goal for a more efficient engine will never disappear. Over the years many different techniques have been explored within the common goal of higher efficiency. Lean combustion has proven to be effective at increasing efficiencies as well as reducing emissions. The purpose of this thesis is to install a modern Cummins QSK19G and perform certain test that will explore the lean combustion limits and other methods that could possibly increase efficiency even more. The entire installation and instrumentation process is documented within this thesis. The engine was installed in the Engines and Energy Conversion Laboratory at Colorado State University. The engine was installed with the hopes of instilling the desire for endless future tests from Cummins as well as other companies seeking this type of research engine. The lean limit was explored in the most detail. Cummins supplied a test plan that satisfied their desired stopping at a lean limit when the coefficient of variance of indicated mean effective pressure reached 5%. For the curiosity of others involved and this thesis, the lean limit was explored further until the engine could no longer ignite the ultra-lean combustion mixture. Friction accounts for a significant loss in a modern internal combustion engine. One role of the engine oil is to reduce these frictional losses as much as possible without causing increased wear. A test was conducted on the QSK19G to explore the effects of varying the engine oil viscosity. Frictional losses of two different viscosity oils were compared to the stock engine oil losses. The fact that reducing oil viscosity reduces frictional losses was proven in the test

“How Do We Actually Do Convergence” for Disaster Resilience? Cases from Australia and the United States

In recent years there has been an increasing emphasis on achieving convergence in disaster research, policy, and programs to reduce disaster losses and enhance social well-being. However, there remain considerable gaps in understanding “how do we actually do convergence?” In this article, we present three case studies from across geographies—New South Wales in Australia, and North Carolina and Oregon in the United States; and sectors of work—community, environmental, and urban resilience, to critically examine what convergence entails and how it can enable diverse disciplines, people, and institutions to reduce vulnerability to systemic risks in the twenty-first century. We identify key successes, challenges, and barriers to convergence. We build on current discussions around the need for convergence research to be problem-focused and solutions-based, by also considering the need to approach convergence as ethic, method, and outcome. We reflect on how convergence can be approached as an ethic that motivates a higher order alignment on “why” we come together; as a method that foregrounds “how” we come together in inclusive ways; and as an outcome that highlights “what” must be done to successfully translate research findings into the policy and public domains

Delineation of geological problems for use in urban planning

Activities of the University of Alabama in support of state and local planning commissions are reported. Demonstrations were given of the various types of remotely sensed images available from U-2, Skylab, and LANDSAT; and their uses and limitations were discussed. Techniques to be used in determining flood prone areas were provided for environmental studies. A rapid, inexpensive method for study was developed by which imagery is copied on 35 mm film and projected on existing topographic maps for measuring delta volume and growth

Analytical Investigation of Saddle Connections for Overhead Sign Trusses with Respect to Strength and Fatigue Performance

Bridge-type overhead truss sign structures (OHTSS) are widely used over active highways across the states. An OHTSS is comprised of a 3D truss and two support frames at each end. The structures are usually made of steel or aluminum. Many state DOTs use their own types of connections that are not documented in specifications. Since 2015, the Kansas DOT has used a type of ‘saddle connection’ at the joints of truss chords and support frame pipes. Wind loads are the primary type of load a sign structure resists besides the gravity load. Since wind loads are periodic, fatigue properties are important in the design of OHTSS. As a newly developed connection, the Kansas DOT sought information regarding the mechanical performance of the saddle connection. Studies were needed to verify the safety of the connections, particularly regarding its fatigue susceptibility. This report present a study mainly aimed at evaluating the fatigue susceptibility of the saddle connections using finite element analysis (FEA). The study consisted of the following four parts: Part 1 - Global behavior analysis: an analysis aimed at determining the global behavior of the structures and the location of critical connections. Linear-elastic material properties were used. Part 2 - Structural Hot Spot Stress analysis: an analysis was performed to determine structural Hot Spot Stresses along each weld in the critical connections identified in Part 1. Linear- elastic material properties were used. Part 3 – Effective notch stress analysis: a linear-elastic analysis using the effective notch stress method to evaluate three welds identified to have larger stresses in Part 2. Linear-elastic material properties were used. Part 4 – Extreme loading analysis: An analysis to evaluate the behavior of the saddle connections and the overall structures under extreme loading and provide comments regarding the strength-related safety of the saddle connections. Elastic-perfectly plastic material properties were used. Sign structures of four span lengths, including 60 ft, 83 ft, 110 ft, and 137 ft, were analyzed in Part 1 and Part 2. The 137 ft span structure was analyzed in part three using the effective notch stress method. The 60 ft and 137 ft span structures were analyzed in part four. In Parts 1 and 2, AASHTO fatigue loads, including natural wind gusts and truck-induced gusts, were applied in six load modes. They included: natural wind blowing from the back, front, and side of sign structures; and truck-induced gusts acting on the right, middle, and left 12 ft of sign trusses. In Part 3, the AASHTO fatigue load of the natural wind blowing from behind the sign structure was applied. In Part 4, the overall structures and the saddle connections were loaded until the analysis terminated. The termination of analysis was governed by loss of stiffness due to the yielding of material. The study resulted in conclusions that the natural wind in the direction facing the sign panel almost always governed the fatigue demand. The bottom saddle connections were more susceptible to fatigue damage than the top saddle connections, especially the stiffener-to-pipe weld in the bottom saddle connection. Fatigue failures of the saddle connections are not likely to occur in expected real use, but attention should be paid to the stiffener-to-pipe weld in the bottom saddle connection. The analysis of the structures under extreme loading suggests that the ultimate strength of saddle connections do not govern the strength of the overall structures.The Kansas Department of Transportatio

Determination of Fatigue Resistance of Coupler Connections in Aluminum Overhead Truss Structures

Overhead truss sign structures (OHTSS) are widely used over highways across the nation. An overhead truss sign structure is comprised of a truss and two supporting frames at each end, and can be made using aluminum or steel. Aluminum overhead truss sign structures are generally more prone to vibration issues due to their light weight (Fouad, et al. 2003). Before 2015, aluminum overhead truss sign structures constructed in Kansas used an identical type of coupling assembly to provide connection between vertical poles and horizontal trusses. There are approximately 450 sign structures that use this type of connections over active highways in the State of Kansas. The coupler connection was designed in the early 1970s. At that time, experimental tests were conducted to determine the static strength of the connection (McCollom 1973), however, no prior research has been conducted to evaluate the fatigue performance of the coupler connection. Many of these connections have now been in service for 30-40 years and research is needed to evaluate the fatigue performance of the connections. This report presents a study aimed at evaluating the fatigue performance of the coupler connections used in bridge-type overhead truss sign structures. It consists of two parts. The first part describes a series of finite element (FE) analyses that were used to determine the behavior of the coupler connections in expected real use. The results indicated that among all loading cases analyzed in this study, the out-of-plane responses of the sign structures were more significant than in-plane responses. The coupler connections behaved like idealized pinned connections, with little to no capability to transfer moments; therefore, the rivets connecting the interior two couplers were found to undergo mostly direct tension and shear. A rational experimental testing plan was developed according to the findings of the finite element analyses. The second part of this study included performing 22 fatigue tests on newly-fabricated coupling assemblies obtained from Steve Johnson Fabrication, Inc. (Wichita, KS), the company that manufactures most OHTSS in Kansas. The experimental tests were conducted to characterize the fatigue performance of the coupler connection, utilizing AASHTO S-N curves. The fatigue tests were conducted in three directions, such that the rivet was loaded in: 1) tension, 2) vertical shear, and 3) horizontal shear. These loading conditions on the rivet represented, respectively: 1) truss out-of-plane shear, 2) truss in-plane shear, and 3) truss chord axial force. The testing program revealed that the coupler connection has much better fatigue resistance when loaded in shear than in tension. Despite poor tensile fatigue performance, fatigue failure is still considered to be unlikely in OHTSS applications, due to very low stress demands found from finite element analyses.The Kansas Department of Transportatio

Lightweight Modular Steel Floor System For Rapidly Constructible And Reconfigurable Buildings

Rapid construction, modularity, deconstruction, and reconfiguration facilitate economy and sustainability allowing for changes in a building’s use over time. Typical one-way composite steel/concrete floor systems lend themselves to terminal construction practices that make assumptions about the occupancy and usage needs that must last through the life of the structure. To address this, a lightweight rapidly constructible and reconfigurable modular steel floor (RCRMSF) system that utilizes two-way bending behavior and cold-formed steel building materials has been developed. RCRMSF improves upon the efficiency benefits of traditional composite steel/concrete flooring systems, reducing beam and girder usage and size, and allowing for highly flexible building configurations and mobility. The system con- sists of a series of prefabricated panels composed of a grid of cold-formed steel channels running in orthogonal directions sandwiched together by steel plates. A simple performance assessment has been formulated and a finite element model parametric study has been carried out in the Abaqus finite ele- ment analysis (FEA) software. The results of the developed performance assessment and FEA study show that RCRMSF systems are suitable for rapidly constructible buildings in terms of strength and serviceability, providing an initial step to fully modular and reconfigurable steel buildings

Ground-truthing AVIRIS mineral mapping at Cuprite, Nevada

Mineral abundance maps of 18 minerals were made of the Cuprite Mining District using 1990 AVIRIS data and the Multiple Spectral Feature Mapping Algorithm (MSFMA) as discussed in Clark et al. This technique uses least-squares fitting between a scaled laboratory reference spectrum and ground calibrated AVIRIS data for each pixel. Multiple spectral features can be fitted for each mineral and an unlimited number of minerals can be mapped simultaneously. Quality of fit and depth from continuum numbers for each mineral are calculated for each pixel and the results displayed as a multicolor image

Measuring User Satisfaction for the Natural Hazards Engineering Research Infrastructure Consortium

The User Forum is a Natural Hazards Engineering Research Infrastructure (NHERI)-wide group focused on providing the NHERI Council with independent advice on community user satisfaction, priorities, and needs relating to the use and capabilities of NHERI. The User Forum has representation across NHERI activities, including representatives working directly with the Network Coordination Office (NCO), Education and Community Outreach (ECO), Facilities Scheduling, and Technology Transfer efforts. The User forum also provides feedback on the NHERI Science Plan. As the community voice within the governance of NHERI, the User Forum is composed of members nominated and elected by the NHERI community for a specified term of 1–2 years. User Forum membership spans academia and industry, the full breadth of civil engineering and social science disciplines, and widespread hazard expertise including earthquakes, windstorms, and water events. One of the primary responsibilities of the User Forum is to conduct an annual community user satisfaction survey for NHERI users, and publish a subsequent Annual Community Report. Measuring user satisfaction and providing this feedback to the NHERI Council is critical to supporting the long-term sustainability of NHERI and its mission as a multidisciplinary and multi-hazard network. In this paper, the role and key activities of the User Forum are described, including User Forum member election procedures, User Forum member representation and roles across NHERI activities, and the processes for measuring and reporting user satisfaction. This paper shares the user satisfaction survey distributed to NHERI users, and discusses the challenges to measuring community user satisfaction based on the definition of user. Finally, this paper discusses the evolving approaches of measuring user satisfaction using other methods, including engaging with the twelve NHERI research infrastructures

Social Aggregation in Pea Aphids: Experiment and Random Walk Modeling

From bird flocks to fish schools and ungulate herds to insect swarms, social biological aggregations are found across the natural world. An ongoing challenge in the mathematical modeling of aggregations is to strengthen the connection between models and biological data by quantifying the rules that individuals follow. We model aggregation of the pea aphid, Acyrthosiphon pisum. Specifically, we conduct experiments to track the motion of aphids walking in a featureless circular arena in order to deduce individual-level rules. We observe that each aphid transitions stochastically between a moving and a stationary state. Moving aphids follow a correlated random walk. The probabilities of motion state transitions, as well as the random walk parameters, depend strongly on distance to an aphid\u27s nearest neighbor. For large nearest neighbor distances, when an aphid is essentially isolated, its motion is ballistic with aphids moving faster, turning less, and being less likely to stop. In contrast, for short nearest neighbor distances, aphids move more slowly, turn more, and are more likely to become stationary; this behavior constitutes an aggregation mechanism. From the experimental data, we estimate the state transition probabilities and correlated random walk parameters as a function of nearest neighbor distance. With the individual-level model established, we assess whether it reproduces the macroscopic patterns of movement at the group level. To do so, we consider three distributions, namely distance to nearest neighbor, angle to nearest neighbor, and percentage of population moving at any given time. For each of these three distributions, we compare our experimental data to the output of numerical simulations of our nearest neighbor model, and of a control model in which aphids do not interact socially. Our stochastic, social nearest neighbor model reproduces salient features of the experimental data that are not captured by the control