The dropped objects are identified as one of the top ten causes of fatalities and serious injuries in the oil and gas industry. It is of importance to understand dynamics of dropped objects under water in order to accurately predict the motion of dropped objects and protect the underwater structures and facilities from being damaged. In this thesis, we study nondimensionalization of dynamic equations of dropped cylindrical objects. Nondimensionalization helps to reduce the number of free parameters, identify the relative size of effects of parameters, and gain a deeper insight of the essential nature of dynamics of dropped cylindrical objects under water. The resulting simulations of dimensionless trajectory confirms that drop angle, trailing edge and drag coefficient have the significant effects on dynamics of trajectories and landing location of dropped cylindrical objects under water.

All residential water meters have published flow rates for which they will operate as designed. These specifications include a maximum operating flow rate, which is recommended not to exceed. However, there are situations which may cause a meter to flow above the maximum flow rate. This thesis explores what effect these surge flows have on residential water meters. Twenty-one 5/8”x3/4” meters were tested in this study: three oscillating pistons, six nutating disks, nine ultrasonic, and three electromagnetic. Testing was done at the Utah Water Research Laboratory using a gravimetric test bench specifically designed for residential water meter testing. The results of this study showed that the ultrasonic meters decreased significantly in accuracy for tests above 35 gallons per minute. The nutating disk and oscillating piston meters were found to be accurate through nearly all surge flow rates tested. The electromagnetic meters were found to be accurate up to 55gallons per minute. Accuracy tests that were performed after surge flows showed that some nutating disk and oscillating piston meters decreased in accuracy at flow rates below two gallons per minute. The electronic meters had similar accuracy before and after surge flows.

<p>Since measurements in engine test cells are closely coupled with high costs it is of interest to use physically interpretable engine models instead of engine maps. Such engine models can also be used to do off-line tests of how new or altered components affects engine performance.</p><p>In the thesis an existing mean value engine model will be extended with a model of a compressor bypass valve. A controller for that valve will also be developed. The purpose with that controller is to save torque and boost pressure but at the same time avoid having the compressor entering surge during fast closing transients in the throttle position.</p><p>Both the extension and controller is successfully developed and implemented. The extension lowers the pressure after the compressor and increases the pressure before the compressor when the bypass valve is being opened and the controller shows better results in simulations than the controller used in the research lab. By using the proposed controller, as much as 5 percent higher torque can be achieved in simulations.</p><p>Finally there is a discussion on wastegate control alternatives and the use of TOMOC for optimization of wastegate control.</p>

<p>Samhällets utveckling i kombination med förändringar inom hälso- och sjukvården ökar risken att drabbas av en allvarlig händelse. Hälso- och sjukvården måste därför anpassas för att kunna hantera situationer med ett stort skadeutfall, i samma utsträckning som en oväntad minskning av tillgänglig kapacitet, till exempel vårdplatsbrist. Genom att hitta svagheter i verksamheten så ökar möjligheterna att åtgärda dessa och därmed förmågan att kunna upprätthålla de ordinarie målen för vård och behandling av patienter vid en allvarlig händelse. Syftet med denna studie var att utveckla och testa en arbetsmetod för att systematiskt kunna analysera och utvärdera katastrofmedicinsk beredskap, samt identifiera, orsaksbestämma, åtgärdsanalysera och mäta förmågan att hantera de för Landstinget i Östergötland (LiÖ) väsentliga områdena av katastrofmedicinskt beredskap. För detta ändamål utvecklades en arbetsmetod genom att kombinera en av Katastrofmedicinskt Centrum skapad strukturmall med den metod som Patientsäkerhetsenheten inom LiÖ använder sig av vid riskanalyser. Strukturmallen utgår ifrån Socialstyrelsens föreskrifter och allmänna råd (2005:13) om vad Hälso- och sjukvården särskilt bör uppmärksamma i relation till vad dess verksamhet skall baseras på. Resultatet visar att strukturmallen i kombination med patientsäkerhetsmetoden ger möjlighet att systematiskt utföra riskanalyser inom de identifierade områdena av katastrofmedicinsk beredskap. Arbetsmetoden bidrog till en samsyn om olika begrepps betydelse, samt identifiering och värdering av för den katastrofmedicinska beredskapen förekommande risker. En fortsatt utveckling av metoden krävs för att kunna analysera och utvärdera effekter av riskminskande åtgärder.</p> / <p>The aim of the study was to develop and test a new methodology for a systematic analysis of disaster preparedness in the County Council of Östergötland. The aim was also to identify, categorise and create measurability of the surge capacity within important fields of the disaster preparedness of the County Council of Östergötland.</p><p>The methodology is based on the use of a template developed by the Centre for Teaching and Research in Disaster Medicine and Traumatology (KMC), in combination with a validated patient risk assessment tool. The KMC template is based on national regulations and guidelines issued by the Swedish National Board of Health and Welfare. The template includes, in accordance with the board, what disaster preparedness should pay particular attention to in the planning process, in relation to the different components of disaster preparedness.</p><p>The results demonstrate that the template in combination with the risk assessment tool made it possible for an expert group to systematically conduct risk analysis within the identified areas of the disaster preparedness. Future development of this methodology will be needed in order to analyse and evaluate the effects of risk mitigation measures.</p>

No description available.

No description available.

Since measurements in engine test cells are closely coupled with high costs it is of interest to use physically interpretable engine models instead of engine maps. Such engine models can also be used to do off-line tests of how new or altered components affects engine performance. In the thesis an existing mean value engine model will be extended with a model of a compressor bypass valve. A controller for that valve will also be developed. The purpose with that controller is to save torque and boost pressure but at the same time avoid having the compressor entering surge during fast closing transients in the throttle position. Both the extension and controller is successfully developed and implemented. The extension lowers the pressure after the compressor and increases the pressure before the compressor when the bypass valve is being opened and the controller shows better results in simulations than the controller used in the research lab. By using the proposed controller, as much as 5 percent higher torque can be achieved in simulations. Finally there is a discussion on wastegate control alternatives and the use of TOMOC for optimization of wastegate control.

Dynamic compressors are susceptible to aerodynamic instabilities while operating at low mass flow rates. These instabilities, rotating stall and surge, are detrimental to engine life and operational safety, and are thus undesirable. In order to prevent stability problems, a passive technique, involving fuel flow scheduling, is currently employed on gas turbines. The passive nature of this technique necessitates conservative stability margins, compromising performance and/or efficiency. In the past, model based active control has been proposed to enable reduction of margin requirements. However, available compressor stability models do not predict the different stall inception patterns, making model based control techniques practically infeasible. This research presents active stability management as a viable alternative. In particular, a limit detection and avoidance approach has been used to maintain the system free of instabilities. Simulations show significant improvements in the dynamic response of a gas turbine engine with this approach. A novel technique has been developed to enable real-time detection of stability limits in axial compressors. It employs a correlation measure to quantify the chaos in the rotor tip region. Analysis of data from four axial compressors shows that the value of the correlation measure decreases as compressor loading is increased. Moreover, sharp drops in this measure have been found to be relevant for stability limit detection. The significance of these drops can be captured by tracking events generated by the downward crossing of a selected threshold level. It has been observed that the average number of events increases as the stability limit is approached in all the compressors studied. These events appear to be randomly distributed in time. A stochastic model for the time between consecutive events has been developed and incorporated in an engine simulation. The simulation has been used to highlight the importance of the threshold level tosuccessful stability management. The compressor stability management concepts have also been experimentally demonstrated on a laboratory axial compressor rig. The fundamental nature of correlation measure has opened avenues for its application besides limit detection. The applications presented include stage load matching in a multi-stage compressor and monitoring the aerodynamic health of rotor blades.

ABSTRACT SIMULATION OF FLOW TRANSIENTS IN LIQUID PIPELINE SYSTEMS Ko&ccedil / , Gen&ccedil / er M.S., Department of Mechanical Engineering Supervisor: Prof. Dr. O. Cahit Eralp November 2007, 142 pages In liquid pipeline systems, transient flow is the major cause of pipeline damages. Transient flow is a situation where the pressure and flow rate in the pipeline rapidly changes with time. Flow transients are also known as surge and Waterhammer which originates from the hammering sound of the water in the taps or valves. In liquid pipelines, preliminary design parameters are chosen for steady state operations, but a transient check is always necessary. There are various types of transient flow situations such as valve closures, pump trips and flow oscillations. During a transient flow, pressure inside the pipe may increase or decrease in an unexpected way that cannot be foreseen by a steady state analysis. Flow transients should be considered by a complete procedure that simulates possible transient flow scenarios and by the obtained results, precautions should be taken. There are different computational methods that can be used to solve and simulate flow transients in computer environment. All computational methods utilize basic v flow equations which are continuity and momentum equations. These equations are nonlinear differential equations and some mathematical tools are necessary to make these equations linear. In this thesis a computer program is coded that utilizes &ldquo / Method of Characteristics&rdquo / which is a numerical method in solving partial differential equations. In pipeline hydraulics, two partial differential equations, continuity and momentum equations are solved together, in order to obtain the pressure and flow rate values in the pipeline, during transient flow. In this thesis, MATLAB 7.1 is used as the programming language and obtained code is converted to a C# language to be able to integrate the core of the program with a user friendly Graphical User Interface (GUI). The Computer program is verified for different scenarios with the available real pipeline data and results of various reputable agencies. The output of the computer program is the tabulated pressure and flow rate values according to time indexes and graphical representations of these values. There are also prompts for users warning about possible dangerous operation modes of the pipeline components.

Many Climate Scientists believe that global warming will produce more extreme weather events such as tropical storms, hurricanes, intense rainfall, and flooding. These events are considered to be the most catastrophic natural events for transportation systems especially in coastal areas. Due to the severe damage from storm surge and flooding. Evaluating the magnitude of possible storm surges and their impacts on transportation systems in coastal areas is fundamental to developing adaptation plans and impact assessments to mitigate the damage. This thesis focuses on existing transportation systems in the Georgia coastal area that could be affected by several storm surges. An existing storm surge model is used to estimate the storm surges and the surge heights based on the category, direction, and forward speed of a storm. The ground elevation of the ports, interstates, state roads, railroads, and the principal airports on the Georgia coast are identified through a GIS analysis using the national elevation data set. Having the storm surge elevation and the elevation of the existing infrastructure, a GIS study is performed to identify those parts of the transportation system that will be affected by each type of storm giving results such as the length or sections of transportation assets under or above the surge elevation. A literature review of storm surge, rising sea levels, and their impacts on coastal bridges, roads, airports, ports, and railroads is presented in the thesis. Also, a description of the software used to analyze and estimate the impacts of climate change on transportation systems is described.