This thesis presents an experimental investigation of the fluctuating lift (or side force) coefficient on fixed two dimensional rectangular cylinders for various free stream turbulence intensities and scales. The measurements are made using turbulence producing devices such as grids and circular rods placed upstream of the stagnation line of the model. Measurements are reported for three fixed rectangular prisms with B/H of .5, .67 and 1 where H is the frontal dimension and B is the streamwise width of the body. The method of measurement made it possible to vary the body span so that the correlation of the fluctuating side force over the body span could be investigated. It was shown that for low turbulence intensity, the spanwise correlation of the fluctuating side force over the square cylinders decreases by a large amount with increasing span. For higher turbulence intensity this decrease was reduced, and for U'/U≃10% there was essentially no decrease of fluctuating lift coefficient with increase of span. / Applied Science, Faculty of / Mechanical Engineering, Department of / Graduate

This thesis deals with design of the lift frame with lift capacity1600kg and with calculation of distance between armatures of quides. Lift speed is 0.48 m / s. This thesis also includes final element analysis of the frame in software I-DEAS.

No description available.

This thesis describes the development of a generic design methodology for variable camber flap systems for transport aircraft, intended to be used for cruise and low-speed operations. The methodology was structured after several revisions were performed on conventional high-lift device design methodologies for existing transport aircraft. The definition and detail explanations are given at every phase of the methodology. A case study was performed in order to give an example of the implementation of the methodology where a transport aircraft called A TRA, a design study from previous PhD report, was taken as a model. Experimental work could not be performed, due to budget constraints, so the case study was only carried out using computer-based analyses. Software packages such as MSES-code (a Computational Fluid Dynamic software), CATIA and PATRANINASTRAN were used for this case study to analyse aerodynamic characteristics, layout as well as simulation and structure analyses respectively. The results obtained showed that it was practically feasible to deploy such a high-lift device to transport aircraft when the effect from aerodynamic loads gave minimum effect on structural deformation. The deflections of the flap as well as spoilers under critical loads were below the allowable limits, which had a minimal effect due to the additional lift force generated from the movable surfaces.

In the past, the oil and gas industry has typically used the single gradient system to drill wells offshore. With this system the bottom hole pressure was controlled by a mud column extending from the drilling rig to the bottom of the wellbore. This mud column was used to achieve the required bottom hole pressure. But, as the demand for oil and gas increased, the industry started exploring for oil and gas in deep waters. Because of the narrow margin between the pore and fracture pressures it is somewhat difficult to reach total depth with the single gradient system. This led to the invention of the dual gradient system. In the dual gradient method, heavy density fluid runs from the bottom hole to the mudline and a low density fluid from the mudline to the rig floor so as to maintain the bottom hole pressure. Several methods have been developed to achieve the dual gradient drilling principle. For this research project, we paid more attention to the liquid lift, dual gradient drilling (riser dilution method). This method of achieving dual gradient drilling was somewhat different from the others, because it does not utilize elaborate equipment and no major changes are made on the existing drilling rigs. In this thesis the technical feasibility of using the liquid lift method over the other methods of achieving dual gradient drilling was determined. A computer program was developed to simulate the wellbore hydraulics under static and dynamic conditions, injection rate and base fluid density required to dilute the riser fluid and finally, u-tubing phenomena. In this thesis we also identified some problems associated with the liquid lift method and recommendations were made on how these problems can be eliminated or reduced. Emphases were placed on the effect of u-tubing, injection rate of base fluid at the bottom of the riser and well control issues facing this system.

In the past, the oil and gas industry has typically used the single gradient system to drill wells offshore. With this system the bottom hole pressure was controlled by a mud column extending from the drilling rig to the bottom of the wellbore. This mud column was used to achieve the required bottom hole pressure. But, as the demand for oil and gas increased, the industry started exploring for oil and gas in deep waters. Because of the narrow margin between the pore and fracture pressures it is somewhat difficult to reach total depth with the single gradient system. This led to the invention of the dual gradient system. In the dual gradient method, heavy density fluid runs from the bottom hole to the mudline and a low density fluid from the mudline to the rig floor so as to maintain the bottom hole pressure. Several methods have been developed to achieve the dual gradient drilling principle. For this research project, we paid more attention to the liquid lift, dual gradient drilling (riser dilution method). This method of achieving dual gradient drilling was somewhat different from the others, because it does not utilize elaborate equipment and no major changes are made on the existing drilling rigs. In this thesis the technical feasibility of using the liquid lift method over the other methods of achieving dual gradient drilling was determined. A computer program was developed to simulate the wellbore hydraulics under static and dynamic conditions, injection rate and base fluid density required to dilute the riser fluid and finally, u-tubing phenomena. In this thesis we also identified some problems associated with the liquid lift method and recommendations were made on how these problems can be eliminated or reduced. Emphases were placed on the effect of u-tubing, injection rate of base fluid at the bottom of the riser and well control issues facing this system.

In the past, the oil and gas industry has typically used the single gradient system to drill wells offshore. With this system the bottom hole pressure was controlled by a mud column extending from the drilling rig to the bottom of the wellbore. This mud column was used to achieve the required bottom hole pressure. But, as the demand for oil and gas increased, the industry started exploring for oil and gas in deep waters. Because of the narrow margin between the pore and fracture pressures it is somewhat difficult to reach total depth with the single gradient system. This led to the invention of the dual gradient system. In the dual gradient method, heavy density fluid runs from the bottom hole to the mudline and a low density fluid from the mudline to the rig floor so as to maintain the bottom hole pressure. Several methods have been developed to achieve the dual gradient drilling principle. For this research project, we paid more attention to the liquid lift, dual gradient drilling (riser dilution method). This method of achieving dual gradient drilling was somewhat different from the others, because it does not utilize elaborate equipment and no major changes are made on the existing drilling rigs. In this thesis the technical feasibility of using the liquid lift method over the other methods of achieving dual gradient drilling was determined. A computer program was developed to simulate the wellbore hydraulics under static and dynamic conditions, injection rate and base fluid density required to dilute the riser fluid and finally, u-tubing phenomena. In this thesis we also identified some problems associated with the liquid lift method and recommendations were made on how these problems can be eliminated or reduced. Emphases were placed on the effect of u-tubing, injection rate of base fluid at the bottom of the riser and well control issues facing this system.

In the past, the oil and gas industry has typically used the single gradient system to drill wells offshore. With this system the bottom hole pressure was controlled by a mud column extending from the drilling rig to the bottom of the wellbore. This mud column was used to achieve the required bottom hole pressure. But, as the demand for oil and gas increased, the industry started exploring for oil and gas in deep waters. Because of the narrow margin between the pore and fracture pressures it is somewhat difficult to reach total depth with the single gradient system. This led to the invention of the dual gradient system. In the dual gradient method, heavy density fluid runs from the bottom hole to the mudline and a low density fluid from the mudline to the rig floor so as to maintain the bottom hole pressure. Several methods have been developed to achieve the dual gradient drilling principle. For this research project, we paid more attention to the liquid lift, dual gradient drilling (riser dilution method). This method of achieving dual gradient drilling was somewhat different from the others, because it does not utilize elaborate equipment and no major changes are made on the existing drilling rigs. In this thesis the technical feasibility of using the liquid lift method over the other methods of achieving dual gradient drilling was determined. A computer program was developed to simulate the wellbore hydraulics under static and dynamic conditions, injection rate and base fluid density required to dilute the riser fluid and finally, u-tubing phenomena. In this thesis we also identified some problems associated with the liquid lift method and recommendations were made on how these problems can be eliminated or reduced. Emphases were placed on the effect of u-tubing, injection rate of base fluid at the bottom of the riser and well control issues facing this system.

Thesis (doctoral)--Friedrich-Wilhelms-Universität zu Berlin, 1926. / "Sonderabdruck aus: Zeitschrift für angewandte Mathematik und Mechanik, Band 6, 1926, Seite 265 bis 283"--P. [1]. Vita. Includes bibliographical references.

Thesis (M.S. in Aeronautical Engineering)--Naval Postgraduate School, December 2003. / Thesis advisor(s): Raymond Shreeve, E.R. Wood. Includes bibliographical references (p. 41). Also available online.