Spacecraft thermal control is entirely reliant upon radiative heat transfer for temperature regulation. Current methods are often static in nature and do not provide dynamic control of radiative heat transfer. As a result, modern spacecraft thermal control systems are typically 'cold-biased' with radiators that are larger than necessary for many operating conditions. Deploying a variable radiator as a thermal control technique in which the projected surface area can be adjusted to provide the appropriate heat loss for a given condition can reduce unnecessary heat rejection and reduce power requirements. However, the radiative behavior of the apparent surface representing the expanding/collapsing radiator changes in addition to the projected surface area size. This work experimentally quantifies the spectral, directional emissivity of an apparent surface comprised of a series of V-grooves (e.g. corrugated surface), as a function of angle and highlights its emission characteristics that trend toward black behavior. The experimental setup for quantifying this apparent radiative surface behavior is described and utilized to show the influence of surface geometry, direction and wavelength. The experimental design is validated and demonstrated using fully oxidized, nearly diffuse, copper, corrugated test samples. The results presented in this work demonstrate, for the corrugated oxidized copper surfaces tested, that (1) higher emissivity values correspond to higher wavelengths in the spectral range of 2.5 to 15.4 μm (2) apparent emissivity values increase with decreasing V-groove angle resulting in less spectral variation in emissivity and greater blackbody like behavior, (3) azimuth dependence can be relatively small despite the obvious pattern associated with a corrugated surface, (4) as the V-groove angle decreases, higher emissivity values are associated with θ→0° and ϕ→90°. Results provide a foundation for future radiator design, improved spacecraft thermal control methods, and improved emissivity testing methods for patterned or angular surfaces.

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Pallets are the foundation of unit loads and supply chains. They provide a way to store and transport products in an efficient manner. The load capacity of pallets greatly depends on the type of packages carried by the pallet; however, current pallet design methods do not consider the effect of packages on the load carrying capacity of the pallet. This results in excessive use of materials which reduces the sustainability of unit loads, drives costs up, and creates issues for people in the supply chain. The objective of this study was to investigate the effect of a corrugated box's size and head space on pallet deflection and stress distribution on the top of the pallet as a function of pallet stiffness across multiple pallet support conditions. Data analysis identified that box size had a significant effect on the deflection of the pallet. This effect was only significant for warehouse racking across the width and length support conditions. As much as a 53% reduction in pallet deflection was observed for high stiffness pallets supporting corrugated boxes with 25.4 mm headspace when the size was increased from small to large. Meanwhile, no significant effect of box size was found for other supports. The effect of headspace was significant in some scenarios but inconsistent thus more investigation with a larger sample size is recommended. In addition, redistribution of vertical compression stresses towards the supports was observed as a function of the increasing box size. The increased concentration of compression stresses on top of the supports and the resulting lower pallet deflection could significantly increase the actual load carrying capacity of some pallet designs. / Master of Science / Pallets are the foundation of unit loads and supply chains. They provide a way to store and transport products in an efficient manner. The load capacity of pallets greatly depends on the type of packages carried by the pallet; however, current pallet design methods do not consider the effect of packages on the load carrying capacity of the pallet. This results in excessive use of materials which reduces the sustainability of unit loads, drives costs up, and creates issues for people in the supply chain. The objective of this study was to investigate the effect of a corrugated box’s size and head space on pallet deflection and stress distribution on the top of the pallet as a function of pallet stiffness across multiple pallet support conditions. The data from the study identified that box size does have an effect on the deflection of the pallet but, it was only found to be significant for the warehouse racking supports. The highest reduction in pallet deflection was 53% on the high stiffness pallets carrying corrugated boxes with 25.4 mm of headspace as the boxes increased in size. The other support conditions showed no significant effect of the box size. Headspace showed some significant effect in some conditions but was found inconsistent, therefore an investigation with a larger sample size is recommended. In addition, the redistribution of vertical compression stresses towards the supports was observed as a function of increasing box size. This increase in stress on the supports resulted in lower pallet deflection that could significantly increase the actual load carrying capacity of some pallet designs.

Micro-direct methanol fuel cells (micro-DMFC) can be the power supply solution for the next generation of handheld devices. The applications of the micro-DMFCs require them to have high compactness, high performance, light weight, and long life. The major goal of this research project is to enhance the volumetric power density of direct methanol fuel cells (DMFCs). A performance roadmap has been formulated and showed that patterning the planar membrane electrode assembly (MEA) to 2-D and 3-D corrugated manifolds can greatly increase the power generation with very modest overall volume increases. In this project, different manufacturing processes for patterning MEAs with corrugations have been investigated. A folding process was selected to form 2D triangular corrugations on MEAs for experimental validations of the performance prediction. The experimental results show that the volumetric power densities of the corrugated MEAs have improved by about 25% compared to the planar MEAs, which is lower than the expected performance enhancement. ABAQUS software was used to simulate the manufacturing process and identify the causes of deformations during manufacture. Experimental analysis methods like impedance analysis and 4 point-probes were used to quantify the performance loss and microstructure alteration during the forming process. A model was proposed to relate the expected performance of corrugated MEAs to manufacturing process variables. Finally, different stacking configurations and issues related to cell stacking for corrugated MEAs are also investigated.

Kraftliners är något som används till att skapa bland annat ytskiktet till pappersprodukten wellpapp. Wellpapp består av ett lager kraftliner på antigen en- eller vardera sidan av ett vågigt papper, kallat flute. På uppdrag av SCA R&D undersöker detta kandidatarbete möjligheten till att skapa en konceptuell prototyp till en maskin som kan konstruera wellpappsprover på deras laboratorium. Detta för att via tester kunna prediktera hur variationer i wellpappens struktur påverkar dess egenskaper. Arbetet utfördes med hjälp av en iterativ metod där koncept först togs fram och sedan utvärderades repetitivt tills ett slutgiltigt koncept var framtaget. Konceptframtagningen bestod av fem iterationer med faserna konceptgenerering, modellering, prototypframtagning, tester av prototyp och utvärdering. Arbetet resulterade i ett slutgiltigt koncept som ledde till en illustrerad prototyp i mindre skala som visar hur wellpappsprover skulle kunna skapas i SCA’s R&D-laboratorium. / Kraftliners are used to create, among other things, the surface layer for the paper product corrugated board. Corrugated board consists of a layer of kraftliner on either one or both sides of a wavy paper, called flute. On behalf of SCA R&D this bachelor's thesis investigates the possibility of creating a conceptual prototype for a machine that can create corrugated board samples in their laboratory. This is to be able to predict, via tests, how variations in the structure of the corrugated board affect its properties. The work was carried out using an iterative method where concepts were first developed and then evaluated repetitively until a final concept was developed. The concept development consisted of five iterations with the phases of concept generation, modeling, prototype development, prototype testing and evaluation. The work resulted in a final concept that led to an illustrated prototype on a smaller scale that shows how corrugated board samples could be created in SCA's R&D laboratory.

This report investigates whether a FEM model can be used to assess the risk of crack growth in corrugated board. A set of box geometries with cracks at different locations were loaded and then compared using the evaluated J-integral within the FEM software. To validate the results, comparisons have been made between the FEM liner material and real liner material. It is described how the material model that is used in FEM is constructed as well as how the simulated box is built. The box is loaded in two load cases, and a simplification by using a linear elastic material model has been made. The answer seems positive that it may be possible to assess cracks in a corrugated box using FEM, but the model developed in this report needs further testing and improvements. / Den här rapporten undersöker om en FEM modell kan användas för att bedöma risken för spricktillväxt i wellpapp. Olika lådgeometrier med sprickor belastades och jämfördes med hjälp av FEM-program genom uppmätt J-integral. För validering av resultat så jämfördes resultat från linermaterial modellerad i FEM med materialtest av verkligt linermaterial. I rapporten beskrivs det också hur materialmodellen som används i FEM är konstruerad samt hur lådmodellen är byggd. För jämförelsen av J-integral är lådmodellen belastad med två olika lastfall, därutöver är materialmodellen förenklad så att en linjärelastisk modell används.Svaret till inledande frågan verkar vara att det är möjligt att bedöma sprickor i wellpapp genom användning av FEM. Dock behöver metoden som används i denna rapport fler tester för valideringar samt andra förbättringar.

The aims of the thesis were to study how washboarding (the undulations present on the surface of corrugated cardboard used to manufacture boxes) relates to the mechanical properties of paper and the board manufacturing conditions and to examine the impact of washboarding upon the structural integrity and printability of corrugated cardboard packaging. A digital image profilometry technique was developed to measure the washboarding profiles of corrugated board. This technique was used to measure the washboarding depth and profiles for a range of corrugated boards, some constructed manually and some machine manufactured. This enabled a study into how a change in the mechanical properties of paper and glue affect washboarding depth. The effect that the speed of machine manufacturing had upon the degree of washboarding was also determined. A study of how environmental conditions affect washboarding geometry was undertaken. The effects of the extent of washboarding upon a range of board performance measures were tested empirically and modelled using Finite Element Analysis. These were edgewise compression testing (ECT), three-point bend, and MD-Shear (an Amcor Ltd. proprietary test). A method was developed to measure full-tone print coverage of corrugated board and was used to study how washboarding affects the printing quality of corrugated board.