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One of the most common PET isotopes, 18F, is mainly produced in liquid targets. The production yield depends linearly on the proton beam current used. However, for a fixed proton-beam energy increasing the current of the proton beam results in depositing increasing amounts of heat into the enclosed water target chamber and eventually in its failure. Hence, understanding the thermodynamics of a water target chamber could lead to a target optimization, removing the maximum amount of heat to balance the pressure, increasing the yield and guaranteeing the stability and durability of the system. Work in modeling the thermodynamic processes in a liquid target has also been per-formed by other groups [1-3] and others such as Steinbach [4] have performed analytical analyses of thermal behavior.

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Numerical dam break analyses of Kirazlik&ouml / pr&uuml / Dam are performed under various hydraulic scenarios. Kirazlik&ouml / pr&uuml / Dam is located on the G&ouml / kirmak River near the city of Bartin. The objective of these analyses is to investigate adverse effects of such dam break failure on the regions downstream of the dam. The numerical model used in the simulations is FLDWAV, which is developed by the National Weather Service (NWS) in the United States. It appears that most adversely effected regions are those that are closest to the dam location. The results of these simulations can be used sufficiently to prepare emergency action plans in case of possible failures.

In the present study,transint flow analyses of a long oil pipeline are performed.

In Santa Barbara County, Santa Maria Pacific (an exploration and production company) is expanding their cyclic steam project in a diatomite reservoir. The hilly or mountainous topography and cut and fill restrictions have interfered with the company's ideal development plan. The steep hillsides prevent well pad development for about 22 vertical well locations in the 110 well expansion plan. Conventional production performs poorly in the area because the combination of relatively low permeability (1-10 md) and high viscosity (~220 cp) at the reservoir temperature. Cyclic steam injection has been widely used in diatomite reservoirs to take advantage of the diatomite rocks unique properties and lower the viscosity of the oil. Some companies used deviated wells for cyclic steam injection, but Santa Maria Pacific prefers the use only vertical wells for the expansion. Currently, the inability to create well pads above 22 vertical well target locations will result in an estimated $60,000,000 of lost revenue over a five year period. The target locations could be developed with unstimulated deviated or horizontal wells, but expected well rates and expenses have not been estimated. In this work, I use a thermal reservoir simulator to estimate production based on five potential development cases. The first case represents no development other than the cyclic wells. This case is used to calibrate the model based on the pilot program performance and serves as a reference point for the other cases. Two of the cases simulate a deviated well with and without artificial lift next to a cyclic well, and the final two cases simulate a horizontal well segment with and without artificial lift next to a cyclic well. The deviated well with artificial lift results in the highest NPV and profit after five years. The well experienced pressure support from the neighboring cyclic well and performed better with the cyclic well than without it. Adding 22 deviated wells with artificial lift will increase the project's net profit by an estimated $7,326,000 and NPV by $2,838,000 after five years.

With the high costs of flight testing, especially at hypersonic speeds, ground based facility testing of scramjets becomes an attractive option. The expansion tube is the only facility currently that can offer full flight property duplication at the total pressures and total enthalpies required, while maintaining correct chemical composition. Due to difficulties with short test times and unsteady flow phenomena, scramjet testing in these facilities has not been thoroughly investigated. This study examines these issues, in order to explore the practicality of testing a full ’tip to tail’ scramjet engine at a true flight replication condition in an expansion tube facility. An investigation was initially undertaken on the large X3 expansion tunnel facility to maximise test time and core flow, aimed at producing a 30 km altitude, Mach 10 flow condition. This was identified as the limitation point of the T4 reflected shock tunnel, which has generally been accepted to produce reliable scramjet data for propulsion tests. Using a condition that is also able to be produced in the T4 facility, will permit direct comparison of data between the two facilities in the future, providing confidence in results from expansion tube facilities. Both experimental measurements and numerical calculations showed that the limitation of the test time was due to large boundary layer growth after transition, which engulfed the entire core flow 200 μs into the test time. This phenomenon is likely to affect all scramjet duplication conditions in expansion tubes, as the flow properties are conducive to boundary layer transition occurring. Two solutions where proposed and investigated in order to overcome the flow disruption caused by boundary layer transition; the use of a steady expansion nozzle at the acceleration tube exit; the use of hydrogen as an accelerator gas. Since the smaller X2 facility had a Mach 10 steady expansion nozzle and X3 was decommissioned for the free piston driver to be upgraded, the investigation was shifted to X2. Due to a restricted test time of 550 μs, the static pressure of the flow condition was increased to allow a reduction in the length of the scramjet (pressure-length scaling). A combination of experimental and numerical calculations of the facility was used to define the flow properties. With the confidence of overcoming the phenomenon associated with boundary transition in the X2 facility, numerical modelling of the X3 facility with a steady expansion nozzle was then undertaken to show a 1 ms condition could be produced. Although initially promising, the hydrogen accelerator gas solution requires further investigation. A two dimensional scramjet was designed with upstream injection for testing in X2. This was a three shock inlet with a constant area combustor and a planar thrust surface. Since the flow condition involved changes in flow properties during the test time, aninvestigation of the appropriateness of a quasi steady analysis was undertaken. Using a fuel off simulation of the scramjet duct with the transient inflow properties from the X2 facility nozzle exit, the convective terms for pressure were shown to be two orders of magnitude larger than local terms indicating the dominance of the convective terms change in flow properties at any location allowing quasi-steady flow to be assumed. A normalisation procedure was developed to deal with the transient nature of the data and to accurately represent the axial progression of the gas through the duct. The numerical simulations were also used to show that both flow establishment was achieved and that impulsive starting of the intake would occur. Experimentation with the scramjet using static pressure measurements throughout the body side of the engine provided verification of supersonic combustion. This was verified by the doubling of the static pressure from the start to the end of the combustor for an air test gas, whereas with a nitrogen test gas no significant change in pressure occurred. Effects of fuel equivalence ratio, injector size and cowl position were also investigated. A net inviscid thrust was predicted, using the quasi-steady flow analysis, indicating a specific impulse of 183 s. This work provides evidence to validate the use of expansion tube facilities for experimental testing of scramjets at flight duplication conditions. Limitations due to boundary layer transition flow effects has been shown to be avoidable. Numerical simulations of the facilities showed good agreement with experimental measurements, allowing definition of freestream properties and can now be applied to further scramjet conditions with confidence. Stable, supersonic combustion was shown to be produced for these expansion tube conditions. Coupling the transient simulation of the flow condition with a numerical calculation of the fuel off experimental scramjet has been useful in both verification of the design and performance predictions. Appropriate techniques have been presented to analyse scramjet pressure and thrust measurements where transient effects are present in the freestream.

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