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This master thesis is covering the modeling of the melting process in a tank filled with AdBlue. Due to AdBlue freezing at temperatures below -11 degree there is a need to add heat to be able to secure dosing in all situations. A rig for simulating freezing conditions is created with the possibility to store AdBlue in temperatures down to -40 degree. Temperatures are measured in and around the tank containing AdBlue and in the equipment used for adding heat. Two models are created from physical relations to estimate the mass of AdBlue melted, a static temperature model and a dynamic temperature model. The static model shows good results when calibrated at this specific setup and is very easy to use. The dynamic temperature model is more advanced but describes the real physical system better without external calibration.

This diploma thesis focuses on checking of impact of urea concentration on refractive index of the liquid for selective catalytic reduction. The attention in the introduction part is paid on basic optical terms and laws, particularly on refractive index. Furthermore, the measurement of refraction index is described through particular refractometers and utilization of the refractive index of the liquid in technical practice. In the second part the thesis is focused on problematics of creation of nitrogen oxide emissions, aqueous solution of urea and on description of the construction of the system of selective catalytic reduction. The last, practical part of the thesis includes methodics of measuring of the refractive index of the aqueous solution of urea in various concentrations of urea. The experimental measurement was carried out in laboratories of the Department of Technology and Automobile Transport of Mendel University in Brno. In the conclusion of the practical part are data gained by measuring graphically and statistically evaluated and they are commented appropriately.

This thesis called "Influence of an operation mode of a tractor on function of selective catalytic reduction system" describes various operation modes of the tractor, when aqueous solution of urea (AdBlue) was injected into selective catalytic reduction system. The first part jkdeals with particular pollutants in exhaust fumes. Formation of pollutants and their impact on humans and environment is described in this chapter. The second part describes individual technical systems used to lower harmful components, especially selective catalytic reduction system. The last part concentrates on practical measuring of operating parameters of the tractor, particularly consumption of aqueous solution of urea conducted in different modes of a motor. Part of the experimental measuring is graphic and verbal evaluation.

Táto diplomová práca sa zaoberá optimalizáciou validačných testov pre produkt firmy Robert Bosch určený na úpravu výfukových plynov vznetových motorov, tzv. Denoxtronic 5.x, konkrétne jeho najkomplikovanejšiu časť – Pump Module. Zhrnutím a analyzovaním porúch objavujúcich sa v reálnej prevádzke tak poskytuje spätnú väzbu pre oddelenie vývoja a navrhuje, akým mechanizmom by mali byť v budúcnosti validačné testy optimalizované.

As the emission legislation becomes more stringent, higher demands are put on the aftertreatment system in trucks. For dealing with nitrous oxides, AdBlue® (urea–water solution) is injected into the exhausts which evaporates and reduces nitrous oxides to nitrogen. At low exhaust temperatures, it is more difficult to evaporate the injected AdBlue® as the exhausts contain less energy. The injected solution may instead form a wall film. In this wall film, side reactions can occur which leads to the formation of deposits. This thesis aims at understanding how and when wall films and deposits are formed. To achieve this, a test rig that allowed visual and infrared observations of the process and variation of governing properties was designed and built. The results show that thicker plates can sustain higher dosages than thinner plates since the temperature drop and film area are smaller for the thicker plate. It was also observed that at plate temperatures >340 °C, the water in the impacting spray evaporated, leaving a urea dust in the gas phase. It is also clear that deposits form faster at higher gas temperatures (> 350 °C) compared to at lower temperatures (200–250 °C). The deposits form at the edge of the wall film in a region with a temperature higher than in the middle of the wall film. At lower temperatures, a wall film that spreads out over a very large area is formed and after a longer time period, deposits form at obstacles and at the wall film edge. Experiments for 2 h at lower temperatures left approximately the same amount of deposits as experiments for 30 min at higher temperatures. / När lagkraven blir strängare sätts högre krav på efterbehandlingssystemet i lastbilar. För att få bort nitrösa gaser injiceras AdBlue® (urea–vattenlösning) in i avgaserna vilken förångas och reducerar de nitrösa gaserna till ofarligt kväve. Vid låga avgastemperaturer är det svårare att förånga den injicerade AdBlue®–lösningen då avgaserna innehåller mindre energi. Den injicerade lösningen kan istället bilda en väggfilm. I denna väggfilm kan sidoreaktioner ske vilket leder till bildning av utfällningar. Detta examensarbete syftar till att öka förståelsen för hur och när väggfilmer och utfällningar bildas. För att uppnå detta designades och byggdes en testrigg i vilken visuella och infraröda observationer kan göras och influerande parametrar varieras. Resultaten visar att tjockare plåtar kan utstå högre doseringar jämfört med tunnare plåtar, eftersom lägre temperaturminskning och film area uppmätts för den tjockare plåten. Det sågs också att vid plåttemperaturer >340 °C så förångades vattnet i AdBlue®-lösningen först och efterlämnade ett ureadamm i gasfasen. Det konstaterades också att utfällningar bildas snabbare vid högre gastemperaturer (> 350 °C) jämfört med vid lägre temperaturer (200–250 °C). Utfällningarna bildas vid kanten av väggfilmen i en region som har en temperatur som är högre än den i mitten av väggfilmen. Vid lägre temperaturer bildas en väggfilm som sprider ut sig över en stor area och med tiden bildas utfällningar vid hinder och vid filmkanten. Experiment under 2 h vid låg gastemperatur gav jämförbara mängder utfällningar som experiment under 30 min vid högre temperatur.

Detta arbete har utförts i Rottne mot Rottne Industri AB under hösten 2018 och är ett examensarbete för programmet högskoleingenjör Teknisk design med inriktning produktdesign, D0023A, vid Luleå tekniska universitet. Rottne Industri AB tillverkar skogsmaskiner i varianterna skördare och skotare. I dag har de två olika storlekar på AdBluetankar. AdBlue är en vätska som tillsätts i avgassystemet för att minska utsläpp av kväveoxider. De har problem med att tankarna ibland spricker och de har spruckit vid infästningen. På grund av detta och att tankarna är gjorda i rostfritt stål som är relativt dyrt, vill de istället att tanken ska vara gjord i plast. Målet för arbetet har varit att utforma en AdBluetank och dess monteringsanordning med hänsyn till montering samt att tillfredsställa Rottne industris krav och önskemål. Arbetet har använt en användarcentrerad process som utgår från IDEO- the field guide to human-centrerad design med tre olika faser. I första fasen samlades det in information om den befintliga tanken och hur den monteras. Även information om bland annat AdBlue, användarcentrerad design, plast och lämpliga tillverkningsmetoder för denna produkt samlades in. I andra fasen användes den information som samlades in i första fasen till att generera idéer genom olika kreativa metoder. Utifrån de kreativa metoderna kombinerades idéerna till fyra koncept Pussel, Hörn 106°, Låda och Jto, som utvärderades. Utifrån utvärderingen valdes det att ta vidare koncepten Pussel och Hörn 106° till nästa fast. I sista fasen hades kontakt med ett plasttillverkningsföretag som fick ge feedback på koncepten, och utifrån det samt utvärderingen valdes koncept Pussel att vidareutveckla. Det slutliga konceptet blev två olika storlekar på plasttank som har styrgeometri för hjälp att drag slangar och kablage. Ny infästning som gör det smidigare att montera tanken än den befintliga samt lättare att komma åt.

This diploma thesis deals with the issue of nitrogen oxides emissions in exhaust gases and possibilities of their reduction. The task of the thesis was analysis of systems for NOX reduction by contemporary diesel engines, design and construction of NOX reduction device for given diesel engine, then verify functionality of this system compiled from commercially available components. In the last part of thesis available measurements will be made with an analysis of achieved results.

Diploma thesis deals with the exhaust system able to pass emission restrictions Stage IV. How emissions are produced as well as how could be minimized is described. Analysis of components lay out necessary to AdBlue injection is mentioned. Main part of this paper handle with given design of exhaust system combining diesel particulate filter, as well as filters required to reduce nitrogen oxides. Strength analysis covering vibrations, welds, fatigue and life is concluded. Thesis is made for Zetor Tractors a.s. purposes.

In the time line of world industrial age, the most important era begins in the late 18th century when the use of fossil fuels was growing intensively. This approach has continued and developed up to the 20th century. Besides, this trend has had side effects like polluting environment. Air pollution is one of the critical issues nowadays that stems from using hydrocarbon fuels. One type of the problematic compounds in polluting air is nitrogen oxides that can be produced in combustion process from engines and industrial plants. Different solutions have been suggested to remove air polluting compounds. One method for removing nitrogen oxides is using the mechanism of Selective Catalytic Reduction in silencer of engines. This method has become practical in trucks’ engines. Therefore, research on SCR chemistry is important for improving the usage of this method in removing nitrogen oxides. SCR has its own problems when used in trucks. One of the problems is formation of white clumps on pipe wall of silencers using SCR which can cause back pressure in the engines and costs a lot to remove them from engines.  This report evaluates the effect of alternative fuels on SCR chemistry .Different parameters affecting deposit formation are studied and evaluated. Ethanol is one of the controversial fuels used in engines and acetic acid is one its byproducts. Also, urea and its by products are important materials in SCR chemistry, too. Consequently, the first part of the report studies the influence of acetic acid and Ferrite steel, one of the usual steels in silencers of engines, on urea, biuret and cyanuric acid decomposition. The instruments used in the first part include TGA-DSC (Thermo Gravimetric Analysis-Differential Scanning Calorimetric) which is connected to FTIR (Fourier Transform Infrared Spectroscopy).In the second part of the report, the effect of diesel exhaust and ethanol exhaust on cyanuric acid evaporation rate is evaluated. Cyanuric acid is the main compound forming deposit in silencers. The instrument used in the second part is TGA. The third part consists surveying effect of Adblue, aqueous solution of urea, and additivised Adblue, surfactant added Adblue to improve its efficiency, in a patented rig that is scaled down of a silencer of truck. The most important result for the first part includes the effect of Ferrite steel treated with acetic acid that accelerated the decomposition of cyanuric acid. This result can be investigated more in order to be used in silencers to accelerate the decomposition rate of clumps formed. In the second part, it is found out that cyanuric acid evaporates faster under ethanol exhaust than diesel exhaust. The third part’s results shows that in the current assembly of pipes in the rig, Additivised Adblue loses its improved efficiency which is an interesting result for engine welding in order to avoid this type of connection in engines.