As the aerospace industry moves into more automatic systems and fully automatic systems the need for automatic air to air refuelling is becoming essential to create an optimal aircraft system. It is not only needed for UAVs but also for piloted aircraft. For the aircraft to connect with the hose is a difficult procedure where a lot of things can go wrong. Creating an automatic system will remove any human error out of the procedure to create a more efficient refuelling procedure. This study is taking a look at relative navigation methods to connect the receiver aircraft with the hose in a probe and drogue refuelling system which can be used for an automatic aircraft system for refuelling.         To investigate different relative navigation methods a simulation environment was built using the relative position between each part of the system, the tanker, the hose, the drogue and the receiver. The system environment effects are also implemented to create an accurate environment that includes turbulence, wake effects, wind and bow wave effects. The complexity of each part differs from each other. The two aircraft, tanker and receiver, are modelled in 1 and 3 degrees of freedom where the hose and drogue is modelled in 5 degrees of freedom to simulate the procedure. Using this simulation environment two different methods were tested, a straight on approach where the probe of aircraft aimed to always be aligned with the drogue and an offset approach where the receiver aimed to try to predict the movement of the drogue.         The findings from the simulation showed that analysing the bow wave effect on the drogue to then predict its movement by approaching with an offset was the most optimal approach. It allowed the receiver to do fewer movements during critical parts of the refuelling procedure and also were able to successfully dock during turbulent environment        I can conclude that using relative navigation that using a probe and drogue air to air refuelling an automatic system should be able to work. The simulation can be expanded upon to create a more realistic environment that can give a more accurate representation of the real world dynamics. The aerodynamics of the aircraft need to be expanded upon and the aerodynamics of the disturbances can be more accurately implemented.

Industrial gas turbines reach temperatures of 1500-2000K at high rotational velocities which means that much effort is spent on the design of an efficient cooling system. With the recent advances of the additive manufacturing (AM) industry, new design opportunities have open up for many industries and applications, including the design of cooling systems. However, a significant surface roughness will be present in AM components compared to traditionally manufactured components. An increased surface roughness inside a channel will affect both the heat transfer and pressure loss. The performance of AM channels are therefore not fully known and needs to be examined experimentally on the actual material to fully capture the effects of the increased surface roughness. The aim with this project is to experimentally investigate the thermal performance and pressure losses experienced in AM channels due to surface roughness. This was done by using a Steady State Heat Transfer rig which was assembled and verified. AM and aluminium test channels were mounted in a copper block which was insulated and heated up by electrical heaters. The test channels were then subjected to an air flow of constant mass flow. Temperature and pressure measurements were made at the inlet and outlet together with mass flow measurements and copper block temperature measurements. The Nusselt number and Darcy friction factor were used to evaluate the heat transfer and pressure losses experienced in the channels. The results showed that the heat transfer and friction factor increased significantly for the AM channels compared to smooth channels. Both the heat transfer and friction factor increased when the relative roughness of the channels increased. This project was executed at Siemens Energy in Finspång at the Fluid Dynamic Laboratory and is a part of the work of obtaining thermal performance data for mini-channels manufactured by AM.

The thermal design of the spacecraft ensures the unobstructed and smoothoperation of the spacecraft under the harsh space conditions. As small satellitesare getting more accessible and standardized, their uses are growing more intomission scenarios which are conventionally used by larger satellites. High altitudeorbits are generally used by satellites which will need higher ground coverage, Deepspace observations,and missions that want to study the radiation belts around theEarth.In this thesis we study the impact of the space environment on a 6U CubeSatin a Highly Elliptical Orbit (HEO) around Earth. The Black Body loading andtemperature graphs of the spacecraft in various orbital seasons, the impact ofloading due to major heat sources and its variation with orbit perturbations, theimpact of orbital inclination and satellite rotation on the loading of the satelliteare studied.The orbital loading simulations are performed in NX space systemsthermal solver to study the loading profile on the spacecraft model, based on whichfurther studies are performed to find possible solutions that can be applicable forthe solution. Foresail-2 mission design is considered for the loading simulation inorbit with Foresail-1 mission as the heritage mission. The thermal solutions henceapplicable for consideration are presented.

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Propagation of laser beams through complex flow field caused by radar system housing has been an important topic for many years dating back to the mid 1960s. Applications for radar systems range from missile defense, directed energy to target designation and tracking. Complications are introduced when laser systems are no longer stationed on the ground, but instead mounted on airplanes traveling at subsonic, transonic and supersonic speeds. Housing systems have been developed with a variety of different designs with some designs more optimal for decreasing laser aberrations than others. The work presented strives to characterize flow around a hemispherical configuration (D = 10.16 cm) for a turret housing system in the supersonic flow regime. Multiple diagnostic tests were conducted at the Florida Center for Advanced Aero-Propulsion in the Polysonic Wind Tunnel Facility. Shadowgraph visualization, surface oil flow visualization, static pressure and unsteady pressure data characterized the complicated supersonic flow field around a hemisphere. Observations were conducted at Mach 2 while Reynolds number changed, ReD = 1.8 ∗ 106 and ReD = 3.6 ∗ 106. Complex shock system consisting of a lambda shock and detached bow shock were observed upstream of the hemisphere center through shadowgraph images. While a shock-let system was developed between the foot of the lambda shock and the detached bow shock from the unsteady boundary layer shockwave interaction. Surface oil flow visualization accented the development of an axisymmetric horseshoe vortex and the presence of a secondary shock location upstream of the hemisphere. A centerline static pressure distribution quantified the visualization techniques. A stagnation point of 30◦ was observed on the body for both ReD case. While, flow separation occurred at slightly different locations on the hemisphere; flow separated at 103◦ for ReD = 1.8∗106 and 107◦ for the ReD = 3.6 ∗ 106. Location of flow separation is further strengthen by the unsteady pressure data as the energy fluctuations are less on the separation line for the different Re cases. The study found that flow structures for different ReD cases were similar, except for the strength of the different flow features; as the flow feature magnitudes were greater for ReD = 3.6 ∗ 106 case. Also observed from the unsteady pressure measurement data, the wake structure behind the hemisphere were different in nature as the wake structure for the ReD = 1.8 ∗ 106 case was larger than the ReD = 3.6 ∗ 106 case. Planar Particle Image Velocimetry was conducted in the Pilot Wind Tunnel Facility at the Florida Center for Advanced Aero-Propulsion on a dynamically similar flow (M = 2,ReD = 1.8∗106). Planar PIV for different Z/D planes were also measured on a D = 19.05 mm hemisphere, which highlighted the presence of an expansion fan at the apex of the hemisphere with decreasing effects on the external flow field as flow moved further away from the centerline of the hemisphere. The results presented in this work characterized supersonic flow around a hemisphere and has laid the groundwork for the development of active or passive flow control techniques in order to minimize flow structures, which ultimately lead to less aero-optical aberrations. / A Thesis submitted to the Department of Mechanical Engineering in partial fulfillment of the requirements for the degree of Master of Science. / Fall Semester 2017. / November 9, 2017. / Characterization, Flow, Hemisphere, Supersonic / Includes bibliographical references. / Rajan Kumar, Professor Directing Thesis; Louis N. Cattafesta, III, Committee Member; Emmanuel G. Collins, Committee Member.

Natural convection is a phenomenon in which a flow of the fluid surrounding a body is induced by a change in density due to the temperature difference between the body and the fluid. This flow can be highly non-linear and turbulent, generating eddies. The complex interaction between the convective, viscous and buoyant forces requires the use of modern turbulent simulation tools for simulation. The accuracy of these tools, due to non-linearity, is difficult to assess. The present study investigates natural convection in nuclear fuel rod bundles using heated rods to simulate the storage of spent fuel in dry casks as a benchmark for simulation validation. Four heated, aluminum cylinders are instrumented and suspended in a rotatable, open-circuit wind tunnel. Particle Image Velocimetry (PIV) is used to non-obtrusively measure the velocity fields for various heating and flow conditions. The system response quantities (SRQs) and inflow conditions are acquired using PIV for use in validation of Computational Fluid Dynamics (CFD) models. All measurements are reported with uncertainties and are repeated for multiple flow conditions and heating scenarios. The boundary conditions, initial conditions and SRQs are compiled and made available for public use in validating CFD models.

Nanoparticles on a substrate have numerous applications in nanotechnology, from enhancements to solar cell efficiency to improvements in carbon nanotube growth. Producing nanoparticles in a cheap fashion with some control over size and spacing is difficult to do, but desired. This work presents a novel method for altering the radius and pitch distributions of nickel and gold nanoparticles in a scalable fashion. The introduction of alumina capping layers to thin nickel films during a pulsed laser-induced dewetting process has yielded reductions in the mean and standard deviation of radii and pitch for dewet nanoparticles. Carbon nanotube mats grown on these samples show a much thicker mat for the capped case. The same capping layers have produced an opposite effect of increased nanoparticle size and spacing during a solid state dewetting process of a gold film. These results also show a decrease in the magnitude of the effect as the capping layer thickness increases. Since the subject of research interest for using these nanoparticles has shifted towards producing ordered arrays with size and spacing control, the uncertainty in the values of these distributions needs to be quantified for any form of meaningful comparison to be made between fabrication methods. Presented here is a first step in the uncertainty analysis of such samples via synthetic images producing error distributions.

Precise flow measurement is a critical part of many industries including industrial, hydropower, petroleum, nuclear, and water/wastewater. Lengthy upstream piping is required for many flowmeters to obtain accurate results. Due to piping constraints, sub- optimal flow meter installations can occur. One of these conditions is the installment of a flow meter in close proximity downstream of a double elbow out of plane (DEOP). A DEOP can cause swirl to form in the flow and can cause inaccurate metering results due to the non-uniform flow and pressure conditions. This study investigated the effect of installing a differential pressure producing wedge flow meter downstream of a DEOP on the flow measurement. Computational Fluid Dynamics (CFD) was used for this study in conjunction with physical testing.

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