Energy storage development is an important step for the energy transition, meanwhile Lithium-ion battery is the most common core component of electric vehicles. Over the past decade, investment has been poured into lithium-ion battery production, as a result, the production environment (Clean & Dry room) used for some processes such as Stacking, Electrolyte filling and so on and the energy consumption to maintain this special environment which precise control of air humidity and air cleanliness have become major concerns. In this study, only one production process is concerned: electrolyte filling. During this process, Volatile Organic Compounds(VOCs) are the substance that affects air quality, also it is the reason that no air recovery in this Clean&Dry room before investigating the air quality, which leads to huge energy consumption for treating 100% fresh air.  The main purpose of this thesis is studying the Volatile Organic Compounds(VOCs) distribution in the Clean&Dry room with electrolyte filling activity to check whether the air quality is good enough to be recycled. This part of the study was approached by combining ANSYS FLUENT and the onsite measurement. A secondary objective is studying the energy-saving of dehumidification system with air recirculation system, meanwhile do the environmental analysis and cost analysis. In the end, in order to safely recycle the air in the Clean&Dry room, the Building Automation System should be installed solve the worst case scenario. The conclusions drawn in this study include the Electrolyte Filling machine forms a ”negative pressure room” which means the Volatile Organic Compounds(VOCs) generated from the machine is not likely spreading to the room, and the energy-saving, carbon footprint decreasing, energy cost and the cost of Building Automation System were provided. / Utveckling av energilagring är ett viktigt steg för energiomställningen, samtidigt är litiumjonbatterier den vanligaste nyckelkomponenten i elfordon. Under det senaste decenniet har investeringar gjorts i produktion av litiumjonbatterier, som ett resultat av produktionsmiljön (Rent & torrt rum) som används för vissa processer som stapling, elektrolytfyllning och så vidare och energiförbrukningen för att upprätthålla denna speciell miljö där exakt kontroll av luftfuktighet och luftrenhet har blivit ett stort problem. I denna studie berörs endast en produktionsprocess: elektrolytfyllning. Under denna process är flyktiga organiska föreningar (VOC) ämnet som påverkar luftkvaliteten, vilket också är anledningen till att ingen luftåtervinning i detta rena&torra rum innan man undersöker luftkvaliteten, vilket leder till enorm energiförbrukning för behandling av 100% frisk luft.  Huvudsyftet med denna avhandling är att studera distributionen av flyktiga organiska föreningar (VOC) i Clean&Dry-rummet med elektrolytfyllningsaktivitet för att kontrollera om luftkvaliteten är tillräckligt bra för att kunna återvinnas. Denna del av studien togs fram genom att kombinera ANSYS FLUENT och mätningen på plats. Ett sekundärt mål är att studera energibesparing av avfuktningssystem med luftcirkulationssystem, samtidigt gjorde miljöanalys och kostnadsanalys. I slutändan, för att säkert återvinna luften i Clean&Dry-rummet, bör Building Automation System implementeras för att lösa det värsta scenariot. Slutsatserna som dras i den här studien inkluderar att elektrolytfyllningsmaskinen bildar ett ”negativt tryckrum” vilket betyder att de flyktiga organiska föreningarna (VOC) som genereras från maskinen sannolikt inte sprider sig till rummet, och det energibesparande, koldioxidavtrycket minskar, energi kostnaden och kostnaden för Building Automation System tillhandahölls.

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This thesis is based on the series of scholarly article dedicated to the issue of pumping in the differential scanning chamber of an environmental scanning microscope. The thesis is based on Danilatos’s study where the pumping of the differential pumped chamber is solved by means of the Monte Carlo statistical method. The thesis analyzes gas flow in the experimental chamber using the Pipot tube. The analyses will be used for the design of the experimental chamber which will serve for the experimental evaluation of the flow results in the chamber using the continuum mechanics.

The thesis is focused on the medium dynamics simulation in the environmental scanning electron microscope. Specifically, it researches (examines) the conical aperture location effect in the differential pumped chamber and the width of the pumping channel in this chamber. The theoretical part deals with the environmental scanning microscope generally and other tools used in this thesis, e.g. ANSYS Fluen software, fluid turbulence, medium free path of molecules and electrons scattering. In the practical part, the work is focused on data processing from the ANSYS Fluent program and on their evaluation.

The aim of this work is to create a computational model of radial industrial tumble dryers, to calculate and identify the amount of air that flows through the inside of the drum itself. The calculation will be performed via computational fluid dynamics (CFD). Furthermore, compile transient balance model of mentioned dryers. Perform simulation balance model and compare the results of simulations with experimental measurements. By comparing the experimental data and simulation to determine the degrees of freedom of balance model and evaluate their impact on the assembled transient model. For a better understanding of the drying process, there is constructed a system of differential equations describing heat and moisture within the material being dried on a simple model. In the section devoted to the computational analysis of fluid flow is analyzed existing geometry of the drum, which has a major impact on the flow of air inside the drum itself. Following describes how to simplify its complex geometry entering the computational fluid dynamics. Then, there is carried out a simulation of fluid flow inside the tumble dryers using MRF and Sliding Mesh models. Finally, there is an analysis of the data obtained and determined the average amount of air flowing through the drum itself. On the contrary, the aim of the work is not to create another text tool for students engaged in CFD theme.

Diploma thesis is focused on computational modelling of aerodynamic noise of flow past a solid body. Computation of flow around a cylinder is performed for different meshes and time steps in initial part of the thesis. Results from every computation are compared. Computation aerodynamic noise due to flow around a cylinder is simulated in other part of diploma thesis. In the second benchmark computation, turbulent models have to be considered, because flow with high Reynolds number is turbulent. Computation is based on two different ways: acoustic analogy and direct method. A few different turbulent models is described and is analyzed influence to modelling aerodynamic noise. The results and knowledge of the benchmarks computation have been used in compu-tational modelling of aerodynamic noise of flow around simplified side view mirror. Surface (2D) and spatial (3D) simulations are performed. Based on computation modelling of aerodynamic noise of flow around simplified side view mirror has been designed new geometry, that aim is reduced aerodynamic noise and improved aerodynamic parameters.

Wave energy technology is currently growing and gaining popularity. With around 100 separate technologies researched globally in over 25 countries wave energy are believed to soon be able to compete with other renewable sources such as wind energy. One of the new technologies is WaveTube; a wave energy converter currently under development and in need of technical verification. The basic idea of WaveTube is a partially submerged container with an enclosed fresh water volume. The kinetic energy of the ocean waves are transferred onto the floating container, creating an inner flow in the structure and electricity is generated as the fresh water flows through turbines. Previous small-scale model tests have confirmed the basic idea of WaveTube and an inherent continuation is visualizing and evaluating the inner flow using Computational Fluid Dynamics. A simplified 2D simulation where the WaveTube structure is subject to a pure sinusoidal, rotational motion was believed to be able to give useful information about the inner flow field. However, this Master Thesis project shows that a simulation using ANSYS Fluent of this case is not a successful approach. With inner moving parts a so called dynamic mesh was required, which updates the mesh as the boundaries move. In order for this method to be successful the mesh needs to be of high quality. However, for the complex geometry that WaveTube is no mesh was found to meet the requirements and the calculations using the Volume of Fluid method were not able to proceed.

The focus of this thesis is to analyse the flight characteristics of the blended wingbody (BWB) unmanned aerial vehicle (UAV) Green Raven currently being developed by students at the Royal Institute of Technology (KTH) in Stockholm,Sweden. The purpose of evaluating a BWB aircraft is due to its potential increasein fuel efficiency and payload compared to conventional aircrafts which would enable more sustainable flights. The analysis is conducted in ANSYS Fluent 2020R2 where the goals are to extrapolate lift, drag and pitching moment coefficients,aerodynamic efficiency and evaluate stall patterns. The analysis is conducted with free stream velocities from 5 m/s to 40 m/s with5 m/s increments at angles of attack from −4◦ to stall plus 4◦. The result of thisthesis is that an analysis have not been able to be conducted due to a lack ofcomputational power. Thusly, the conclusion to this thesis is that to be able toperform a complete analysis of the Green Raven, a more powerful computer needsto be used.

During the production of steel in the LD converter the refractory lining is exposed to high temperature emulsion of steel, slag and gas. It protects the steel body of the vessel to come in contact with the molten steel.The main purpose of this work was to observe the temperature distribution profile in converter refractory lining which is very important to understand the life of the refractory lining of the LD converter.In this study, a three dimensional (3D) heat transfer model for the refractory lining of converter was developed. The lining of the refractory material was considered as magnesite brick for inner lining, dolomite for intermediate lining and steel shell as outer part. In order to do the numerical modeling, the CFD software Ansys Fluent 13.0 was used. After considering the proper dimensions, meshing, properties of the lining material and boundary conditions, the modeling in Ansys was performed in two stages. In the first stage, the modeling was performed by assuming that the converter is already heated and the inside temperature of the furnace is 1923K and the outside temperature of the steel body is 300K. In the second stage, the temperature change of the molten steel, slag and the gas was considered as function of blowing time and slag height based on theories from different references. Firstly, the three dimensional (3D) heat transfer model was used for the refractory lining of the converter to show transient heat flow through the lining at different times. Secondly, 3D modeling results from fluent 13.0 was used to develop temperature distribution profile through the lining at different height for different time steps and at different positions with time and also along the converter height from the bottom to top. It has been noticed that refractories in the lining in contact with steel and slag must be of good quality for the reduction of wear cost and downtime and therefore the reduction of refractory cost per ton of steel production.

The near field blast–wave propagation dynamics has been a subject of intense research in recent past. Since experiments on a large scale are difficult to carry out, focus has been directed towards recreating these blast waves inside the laboratory by expending minuscule amounts of energy(few joules),which have been termed here as micro–blast waves. In the present study, micro-blast waves are generated from the open end of a small diameter polymer tube (Inner Diameter of 1.3 mm)coated on its inner side with negligible amounts of HMX explosive (~18 mg/m), along with traces of aluminium powder. Experimental, numerical, and analytical approaches have been adopted in this investigation to understand the generation and subsequent propagation of these micro–blast waves in the open domain. Time–resolved schlieren flow visualization experiments, using a high speed digital camera, and dynamic pressure measurements (head–on and side–on pressures) have been carried out. Quasi one dimensional numerical modeling of the detonation process inside the tube, has been carried out by considering the reaction kinetics of a single(HMX) reaction to account for the reaction dynamics of HMX. The one dimensional numerical model is then coupled to a commercial Navier– Stokes equation solver to understand the propagation of the blast wave from the open end of the tube. A theory that is valid for large scale explosions of intermediate strength was then used for the first time to understand the propagation dynamics of these micro–blast waves. From the experiments, the trajectory of the blast wave was mapped, and its initial Mach number was found to be about 3.7. The side–on overpressure was found to be 5.5 psi at a distance of 20 mm from the tube, along an axis, offset by 30 mm from the tube axis. These values were found to compare quite well with the numerically obtained data in the open domain. From the numerical model of the tube, the energy in the blast wave was inferred to be 1.5 J. This value was then used in the analytical theory and excellent correlation was obtained, suggesting the exciting possibility of using such theories, validated for large-scale explosions, to describe these micro–blasts. Considering the uncertainties in the approximate model, a better estimate of energy was obtained by working back the energy(using the analytical model) from the trajectory data as 1.25 J. The average TNT equivalent, a measure of its strength relative to a TNT explosion, was found to be 0.3. A few benchmark experiments, demonstrating the capability of this novel blast device have also been done by comparing them against the extant large–scale explosion database, suggesting the possibility of using these micro–blast waves to study certain aspects of large–scale explosions.