В данной магистерской диссертации представлены разработки и результаты исследования влияния конструктивных решений на теплоотвод при точении резцом с внутренним воздушным охлаждением. Разработана конструкция резца с увеличенным теплоотводом. Она позволяет существенно расширить область использования резцов с внутренним воздушным охлаждением вместо традиционных резцов с охлаждением СОЖ. Результаты диссертационной работы опубликованы в V номере инженерного журнала «Справочник». Также по результатам проведенного исследования был получен патент на полезную модель №209971 «Металлообрабатывающий инструмент с внутренним охлаждением». Магистерская диссертация состоит из введения, 5 глав, заключения. Объем диссертационной работы – 72 страниц, в том числе 33 рисунка, 6 таблиц. Библиографический список содержит 25 источников. / This master's thesis presents the developments and results of a study of the influence of design solutions on heat removal when turning with a cutter with internal air cooling. A cutter design with increased heat sink has been developed. It allows you to significantly expand the scope of use of cutters with internal air cooling instead of traditional cutters with coolant. The results of the dissertation work were published in the 5th issue of the engineering journal Spravochnik. Also, based on the results of the study, a patent for utility model No. 209971 "Metalworking tool with internal cooling" was obtained. Master's thesis consists of introduction, 5 chapters, conclusion. The volume of the dissertation work is 72 pages, including 33 figures, 6 tables. The bibliographic list contains 25 sources.

Given the coinciding growth-trend in the production of consumer electronics and generation of data, the increase in server halls and data centers, as a means for hosting storage capacity for the generated data, has been prominent over the last decades. The establishment of data centers in already existing infrastructure can entail major changes in terms of energy system design. The activity of data processing and storage is power intensive and as the centers demonstrate substantial heat generation, one of the most important fractions of the energy use comes from the need to provide cooling. The study is a techno-economic analysis purposed for determining the feasibility of different cooling systems for a data center in Sweden. The investigated building currently hosts an industrial printing press hall in which paper printing has been conducted for the several decades. This press hall is subject to a refurbishment process to eventually be converted into a data center. In order to achieve the objectives, a data center building model is developed, designated for the estimation of the internal heat generation and demand for cooling. The design and energy requirements of a number of cooling solutions are then investigated and evaluated using a number of performance metrics: Power Usage Effectiveness (PUE), Capital Expenditure (CapEx), Operational Expenditure (OpEx) and Life Cycle Cost (LCC). More specifically the systems incorporate technologies for utilizing air-based free cooling, ground-source free cooling through borehole ground source heat exchangers (GHEs), mechanical cooling through compressor-driven machines as well as District Cooling (DC). The results of the study show that free cooling is a viable solution for covering the vast majority of the yearly cooling requirements, during sufficiently low outdoor temperatures. Free cooling, provided through borehole GHE’s, is feasible as a partial solution from a technical point of view, to provide cooling capacity during warmer periods. However, it can not alone act to provide a major part of the relatively high and constant cooling capacity requirements throughout the year. All of the investigated scenarios display a similar energy performance in terms of total PUE, at values well below the national average of 1.37. It is also seen, that the scenario that displays the lowest LCC includes a combination of free cooling and compressor-driven cooling. This holds for the studied sensitivity cases. It is found that a combined system incorporating borehole GHE’s and compressor cooling machines perform the best in terms of a low PUE. However, the relative difference in energy performance turns out to be lesser than the relative difference in LCC, when substituting the borehole GHE’s for additional cooling machine capacity. / I takt med digitaliseringen och en ökad global användningen- och produktionen av hemelektronik, vilket föranlett en ökad generering av data, har antalet datahallar blivit allt fler de senaste decennierna. Datahallens syfte är att hantera och bereda lagringskapacitet för den data som genereras vilket involverar en rad energikrävande processer. Upprättandet av datahallar i redan befintlig infrastruktur kan medföra förändringar när det kommer till utformningen av byggnadens energisystem. Att bedriva datalagring och informationsbehandling kräver påtagliga mängder elektricitet vilket medför stor intern värmealstring och därtill behov av aktiv kylning.  Denna studie, som valt att benämnas som en tekno-ekonomisk fallstudie, undersöker lämpligheten i implementeringen av olika kylsystem för ett byggnadskomplex i Stockholm. I byggnadens lokaler återfinns idag en industrihall där det sedan flera decennier bedrivits tryckeriverksamhet. Industrihallen är föremål för en konverteringsprocess för att på sikt bli en datahall. Studien är centrerad kring denna konverteringsprocess. För att utvärdera kylbehoven för den framtida datahallen har en modell utvecklats som uppskattar interna värmelaster samt reglerar inomhusklimatet efter rådande krav på inomhuskomfort. Därefter studeras utformning och energibehov för flera olika typer av kylsystemlösningar där en utvärdering av dessa system görs utifrån indikatorerna Power Usage Effectiveness (PUE), Capital Expenditure (CapEx),Operational Expenditure (OpEx) and Life Cycle Cost (LCC). Mer konkret undersöks kombinerade kylsystem som utnyttjar luftburen frikyla, geotermisk frikyla via bergvärmeväxlare (GHEs), mekanisk kyla via kompressordriven kylmaskin samt regional fjärrkyla. Resultaten från studien visar att frikyla från kylmedelskylare är en lämplig lösning för att täcka majoriteten av datahallens kylbehov över ett år, med undantag för årets varmare perioder. Geotermisk frikyla via borrhål är möjlig som partiell lösning ur ett tekniskt perspektiv, men kan inte enskild leverera en majoritet av effekt- eller energibehovet av kyla. Resultatet visar också att alla undersökta scenarier uppvisar en liknande energiprestanda i termer av total PUE, med värden som underskrider det nationella genomsnittet 1,37. Lägst LCC påvisades för ett system som kombinerar luftburen frikyla via kylmedleskylare och mekanisk kyla via kompressordrivna kylmaskiner. Denna låga LCC är signifikant vilket påvisas i utförd känslighetsanalys. Slutligen konstateras att ett system innefattande luftburen och geotermisk frikyla i kombination med kompressordrivna kylmaskiner resulterar i lägst PUE bland de undersökta scenarierna. Den relativa skillnaden i energiprestanda visar sig vara mindre än den relativa skillnaden i LCC, när geotermisk frikyla ersätts med ytterligare kapacitet från kylmaskiner.

Baigiamajame magistro darbe nagrinėjama problema – dideli energijos poreikiai vėsinimui biurų pastatuose, dėl vis didėjančių mikroklimato kokybės reikalavimų, didesnių šilumos pritekėjimų į patalpas ir šilumos išsiskyrimų dėl naudojamos įrangos. Problemos sprendimui darbe suprojektuotos keturios oro kondicionavimo sistemos su skirtingais šilumnešiais: oru, vandeniu ir freonu. Atsižvelgiant į šilumnešio tipą suprojektuotos ventiliatorinių konvektorių, aktyviųjų šalčio sijų, freoninė ir orinė vėsinimo sistemos. Oro kondicionavimo sistemos analizuojamos remiantis realaus tipinio administracinio pastato pavyzdžiu. Lyginamoms sistemoms buvo atlikti hidrauliniai ir aerodinaminiai skaičiavimai, įvertintos sistemų pradinės investicijos, apskaičiuotos energijos sąnaudos ir eksploatacijos išlaidos. Ekonominio skaičiavimo metu buvo įvertintas sistemų atsipirkimo laikas ir atlikta elektros kainų jautrumo analizė. Šio tyrimo rezultatai parodo, kokia sistema iš visų darbe nagrinėtųjų sistemų yra tinkamiausia biurų pastatams, pagal efektyvų elektros energijos naudojimą ir pradines investicijas. / The final master's work deals with the problem of high energy needs for cooling in office buildings, due to the growing of higher quality requirements for microclimate, higher heat gains in premises and equipment heat emissions used in. To solve the problem four different types of cooling systems with different coolants: air, water and refrigerant are designed at work. Depending on the type of coolant were designed fan coil units, active chilled beams, variable refrigerant volume system and air cooling systems. Air conditioning systems are analyzed on the basis of an example of the real typical office building. The hydraulic and aerodynamic calculations were made, initial investments, energy expenditures and operating costs were estimated for the compared systems. The pay-back time of the systems was assessed and the sensitivity analysis of electricity prices was carried out by economic calculations. The results of this investigation show, which system of all analysed systems at work is the most appropriate for office buildings, according to the efficient use of electricity and the initial investments.

The Master’s thesis dealing with air-cooled condensers is split into four sections. The first section shows an overview of air cooling, introduction into air-cooled condensers of A-frame shape and finned tubes. The second section deals with heat transfer on the steam side and deals with trapped incondensables on the steam side of ACC. The third section deals with heat transfer on the air side, shows a brief overview of fans and selected problems on the air side. In the last section the simplified thedmodynamic calculation of air-cooled condenser is shown.

Batteries play an important role in a sustainable future. As the development for better andsmarter batteries continues, new areas of use emerge boosting its demand. Controlling thetemperature of a battery cell is a vital objective to ensure its longevity and performance. Bothcooling and heating methods can be applied to keep the temperature within a certain rangedepending on its need. This study will review the technical aspects of lithium-ion batteries,observe the different thermal management systems and cooling methods, and lastly examinethe required cooling flow needed for a battery cell to prevent its temperature from rising tocritical levels during its discharge. Using CFD ANSYS Fluent as a simulation tool, the resultsshow that different charging rates, in terms of C-rate, require different rates of mass flow tocontrol the temperature. Simulating the cell with natural convection, the cell peaks at hightemperatures even at lower C-rates, reaching up to 36,4°C and 48,8°C for 1C and 2C,respectively. Applying the cooling method with a flow rate of 0,0077kg/s reduces thetemperature significantly, resulting in temperatures of 26,95°C and 31,27°C for 1C and 2C,respectively.

More and more people are using the internet for data processing, transfer, and storage. With it comes a higher demand for computational power from data servers. Unsurprisingly, the data center industry is becoming an increasingly large industry that is important for people’s daily lives. Data centers cover 2 % of the world’s total electrical consumption and this number is expected to become higher. Running data centers with optimal performance while operating efficiently and as sustainably as possible is a task that is of utmost importance.The way data centers are cooled today is through a CRAH unit that features cooling coils and a fan, the fan blows air over cold coils to prevent damage to server components. Another task for this fan is to create a high differential pressure over the servers using this air, to ensure the air flows in the right direction. The air is uniformly distributed over the servers. With dynamic air-handling measures, it is possible to match the cooling for individual servers, because all servers have different workloads. They generate different amounts of heat. This thesis investigates manual redistribution between servers and how an air-handling damper unit, that sits on the server, is designed to investigate how it can reduce total power draw. Different tests are run in a wind tunnel which houses room for six servers whereas three prototypes are mounted on three of the servers. The main idea to test is that instead of running an even amount of stress on six servers, the same amount of stress is redistributed on only three servers. The ones now running idle have a damper unit blocking the server's rear side. That way the CRAH fan is using less power to create the same differential pressure. Also, the total power draw to all servers is reduced as well. One of the tests was the conventional way of cooling servers today and it had a total power draw of 1362 watts. The test with both redistribution, dampers closed at the rear and turned off servers had a power draw of 951 watts. That is a 30% decrease.

Charging station; PV panel; accumulator; battery; lithium; LiFePO4; Arduino