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This thesis has been conducted with the Life Science company Biotage. The purpose of this project is to develop a new concept of the framework structure for the Flash 400 system. The Flash 400 is a kilogram scale separation system, used for critical absorption purification. The product consists of welded stainless-steel components and include the base, hoist, control panels and the radial compression module and accompanying components. The base structure and control panels were redesigned with focus on cost reduction without major changes to the quality, durability or size. The project started with a pre-study to better understand the product, the current product, possible joining techniques and standard products where examined. The pre-study resulted in a requirement specification that became the base for the concept generation. CAD-files were created for the three concepts that were further developed. Simulations were conducted to find areas for improvements and to ensure the strength of the structure. A cost study with American and Swedish suppliers were executed to determine the cost reduction. The concepts were then evaluated against the current product with criteria from the requirement specification. The project resulted in a viable proposal for the framework design with assembly and manufacturing drawings. The final concept is manufactured with extruded aluminium profiles and screw joints and the cost study indicated a considerable cost reductions can be done. Before the product is altered, tests and further developing is recommended. This thesis is a good foundation for project improvements in the future. / Examensarbetet har genomförts på det medicintekniska företaget Biotage. Målet med projektet var att ta fram ett nytt koncept på utformningen av produkten Flash 400, som är en av företagets nuvarande produkter för kritisk absorptionsrening. Produkten består av en basställning, en lyftanordning, kontrollpaneler och en komprimeringsmodul med tillhörande komponenter och är tillverkad av mestadels svetsat rostfritt stål. I projektet har omkonstruktion av basställningen och kontrollpanelerna genomförts med fokus på kostnadsreducering utan förändring på konstruktionens kvalitet, hållbarhet eller storlek. Arbetet började med en informationsinsamling i form av en förstudie där den nuvarande produkten, potentiella material och komponenter undersöktes. Förstudien resulterade i en kravspecifikation som blev basen för konceptgenereringen. CAD-filer tillverkades för de tre koncept som undersöktes vidare och för att hitta förbättringar genomfördes jämnviktsoch hållfasthetssimuleringar. För att fastställa kostnadsreduceringen utfördes en kostnadsstudie med svenska och amerikanska leverantörer. Koncepten jämfördes utifrån hur väl de klarar av kriterierna i kravspecifikationen gentemot den nuvarande produkten. Projektet har resulterat i ett konstruktionsunderlag med detalj och monteringsritningar. Det vinnande konceptet tillverkas av extruderade aluminiumprofiler med skruvförband. Kostnadsstudien antyder att betydande kostnadsreduceringar kan genomföras. Fortsatt konstruktionsarbete och testning rekommenderas innan några ändringar av produkten genomförs. Rapporten är en god grund för framtida produktutveckling av Flash 400.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22755号 / 工博第4754号 / 新制||工||1743(附属図書館) / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 清野 純史, 教授 高橋 良和, 准教授 古川 愛子 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

The world is continually changing towards more energy efficient alternatives and less pollution. For the traction market, electric powertrains have become the go-to method, superior to both steam and diesel-electric hybrid systems. For subways and trams the natural development now is towards smaller motors with high power output, the goal is to use as much space as possible for the passengers and keep the performance of a larger motor setup. One problem with increasing the power density of the motors is that the accumulated heat from losses also increases per volume. All motors have different efficiency and different limits on temperatures in different parts. For this project a closed, self-ventilated traction motor with axis height 250mm (CSV250) was evaluated. The motor has an input power just above 140kW and the identified limiting factor is the temperature of the bearings, specifically the front bearing located at the fan side of the motor.   An already existing and partly validated ANSYS MotorCAD model was used for full system overview and as a guide to build a COMSOL Multiphysics model of the motor rotor. The COMSOL model could be effectively changed to represent different configurations of the solution. The COMSOL solver is based on the finite element method, FEM, whereas the MotorCAD model is built as a thermal network with lumped parameter method, LPM.    The proposed solution to the high temperature is implementation of heat-pipes in strategic positions. This project only contains evaluation of heat-pipes positioned in the center of the shaft deployed in three different configurations: a short heat-pipe transferring heat from the bearing to the fan, a long heat-pipe transferring heat from the active rotor parts to the fan and a long heat-pipe similar to previous case but with the heat-pipe insulted at the bearing section. The simulations yield performance specifications for the solution design that will give the expected result, complemented with theory this can then give the full appliable solution to the specified problem.   For the short heat-pipe case a decrease in temperature form 116.5 to 96.5°C was achieved in the front bearing by increasing the heat-transfer from the bearing towards the fan with 84.4W. This is well under the preferred temperature of maximum 110°C. In the long heat-pipe case a total of 360W was dispersed through the fan and this lowered the highest temperature point in the rotor from 172.2 to 160.8°C but with the negative effect of increasing the temperature of the front bearing. In the third case the insulation of the long heat-pipe in the bearing section managed to lower this increased temperature from 130.4 to 122.4°C while 360W were still transferred through to the fan. This is under the absolute maximum at 130°C but over 110°C. The results point towards the possibility to increase power density and keeping temperatures manageable using heat-pipes but further work and experiments is needed to prov the concept.

Measurements and predictions of railway-induced vibrations are becoming a necessity in today’s society where land scarcity causes buildings to be put close to railway traffic. The short distances mean an increased risk of the indoor vibration and noise disturbances experienced by residents. In short, the scope of the project is to investigate the transmission loss and vibration level decrease across various junction geometries. The junctions are modelled in both the Finite Element Method (FEM) and the Dynamic Stiffness Method (DSM). Resonances are avoided when possible by using semi-infinite building components. A two-dimensional model that included Timoshenko beams was set up by Wijkmark [1] and solved using the variational formulation of the DSM by Finnveden [2]. The model is efficient and user-friendly but there is no easy way to adjust the junction geometry since the depths of the walls and the floor slabs are the same. From that study, the current topic was formulated. The results presented in this paper indicate that both the Euler-Bernoulli DS model and the three-dimensional FE model have good potential in describing the vibration transmission across the different junction geometries. The two modelling types show more similar results in the analyses of the bending wave attenuation than in the analyses of the quasilongitudinal wave attenuation. One of the probable causes is that the set length of the Perfectly Matched Layers (PML) is not sufficient at such low frequencies. Larger PMLs require bigger geometries that lead to an increase of the computational time. The other proposed reason is the fact that bending waves are created above the asymmetrical junction when the lower beam is excited by a vertical harmonic force. The flexural displacements are neglected in those cases. The results however, were good enough to be satisfactory. Three junction models were investigated and the attenuation is the highest for both wave types in the case with a beam pair attached to the “middle” of an infinite plate. The attenuation is the second highest across the edge of a semi-infinite plate and the lowest across a junction corner of a semi-infinite plate. As part of the suggested future work, the wave transmission between beam and plate needs to be investigated when Timoshenko beams are included in the DS model. In the Euler-Bernoulli beam theory the cross-section remains perpendicular to the beam axis, which is different to the behaviour of solid elements in FEM.