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3D tisk je dolgotrajen in drag proces, ki se v praksi uporabi, ko modela ni možno obdelati s konvencionalnimi načini obdelave. Ekonomičnost procesa 3D tiskanja lahko izboljšamo z ustvarjanjem bolj poroznega materiala. Pri visoko tlačnem litju aluminijevih zlitin prihaja do hitrega odvoda toplote preko materiala orodja v hladilni medij, ki se pretaka po hladilnih kanalih orodja. Poroznost materiala bistveno spremeni prenos toplote in mehanske lastnosti materiala v primerjavi z materiali brez poroznosti. V magistrskem delu je obravnavan prenos toplote v 3D tiskanih vložkih orodij za visoko tlačno litje aluminija. Hitrost odvoda toplote iz ulitka bistveno vpliva na mehanske lastnosti litega materiala, zato je pomembno obravnavati vpliv poroznosti natisnjenih vložkov v orodjih za tlačno litje. 3D printing is a time-consuming and expensive process that is used in practice when the model cannot be processed with conventional processing methods. The economic aspect of 3D printing process can be improved by creating more porous materials. In the case of high-pressure casting of aluminum alloys, heat is rapidly dissipated through the tool material into the cooling medium, which flows through the cooling channels of the tool. The porosity of the material significantly changes the heat transfer and mechanical properties of the material in comparison to the materials without porosity. The master's thesis deals with heat transfer in 3D printed tool inserts for high-pressure aluminum die casting. The rate of heat dissipation from the casting significantly affects the mechanical properties of the cast material, so it is important to consider the influence of the porosity of the printed cartridges in die casting tools.

V diplomskem delu je predstavljeno konstruiranje štirignezdnega orodja za brizganje polipropilenskih pokrovov s ciljem optimizirati hlajenje in posledično skrajšati cikel brizganja. Izvedena je bila analiza možnih konstrukcijskih rešitev, predhodnega dvognezdnega orodja in brizganega materiala. Opravili smo preračune, rezultate le-teh smo nato uporabili za določitev uporabljenega brizgalnega stroja glede na njegovo zapiralno silo. Ob upoštevanju ugotovitev in zahtev smo skonstruirali posamezne komponente in jih sestavili v celoto. Izdelali smo tudi vso potrebno tehnično dokumentacijo za izdelavo orodja. Rezultat je delujoče orodje, ki ima najmanj 5 sekund krajši čas cikla brizganja in 150 % večjo produktivnost v primerjavi s predhodnim orodjem. The thesis presents the construction of a four cavity tool for injection molding of polypropylene lids, for which the target was to optimize cooling and consequently shorten the molding cycle time. We analyzed the possible construction solutions, the previously used two-cavity tool and the molding material. We made calculations on which of the results would then be used to determine the molding machine to use, based on the clamping force of the machine. Taking into account the findings and requirements, we constructed every individual component of the mold and assembled them. Furthermore, we also prepared all the necessary technical documentation for the manufacturer of the mold. The final result is a working mold that has a shorter injection cycle time of at least 5 seconds and 150% higher productivity compared to the previous mold.

Semi-closed greenhouses have been developed in which window ventilation is minimized due to active cooling, enabling enhanced CO2 concentrations at high irradiance. Cooled and dehumidified air is blown into the greenhouse from below or above the canopy. Cooling below the canopy may induce vertical temperature gradients along the length of the plants. Our first aim was to analyze the effect of the positioning of the inlet of cooled and dehumidified air on the magnitudes of vertical temperature and VPD gradients in the semi-closed greenhouses. The second aim was to investigate the effects of vertical temperature gradients on assimilate production, partitioning, and fruit growth. Tomato crops were grown year-round in four semiclosed greenhouses with cooled and dehumidified air blown into the greenhouses from below or above the crop. Cooling below the canopy induced vertical temperature and VPD gradients. The temperature at the top of the canopy was over 5°C higher than at the bottom, when outside solar radiation was high (solar radiation >250 J cm-2 h-1). Total dry matter production was not affected by the location of the cooling (4.64 and 4.80 kg m-2 with cooling from above and from below, respectively). Percentage dry matter partitioning to the fruits was 74% in both treatments. Average over the whole growing season the fresh fruit weight of the harvested fruits was not affected by the location of cooling (118 vs 112 g fruit-1). However, during summer period the average fresh fruit weight of the harvested fruits in the greenhouse with cooling from below was higher than in the greenhouse with cooling from above (124 vs 115 g fruit-1).

Semi-closed greenhouses have been developed in which window ventilation is minimized due to active cooling, enabling enhanced CO2 concentrations at high irradiance. Cooled and dehumidified air is blown into the greenhouse from below or above the canopy. Cooling below the canopy may induce vertical temperature gradients along the length of the plants. Our first aim was to analyze the effect of the positioning of the inlet of cooled and dehumidified air on the magnitudes of vertical temperature and VPD gradients in the semi-closed greenhouses. The second aim was to investigate the effects of vertical temperature gradients on assimilate production, partitioning, and fruit growth. Tomato crops were grown year-round in four semiclosed greenhouses with cooled and dehumidified air blown into the greenhouses from below or above the crop. Cooling below the canopy induced vertical temperature and VPD gradients. The temperature at the top of the canopy was over 5°C higher than at the bottom, when outside solar radiation was high (solar radiation >250 J cm-2 h-1). Total dry matter production was not affected by the location of the cooling (4.64 and 4.80 kg m-2 with cooling from above and from below, respectively). Percentage dry matter partitioning to the fruits was 74% in both treatments. Average over the whole growing season the fresh fruit weight of the harvested fruits was not affected by the location of cooling (118 vs 112 g fruit-1). However, during summer period the average fresh fruit weight of the harvested fruits in the greenhouse with cooling from below was higher than in the greenhouse with cooling from above (124 vs 115 g fruit-1).

Semi-closed greenhouses have been developed in which window ventilation is minimized due to active cooling, enabling enhanced CO2 concentrations at high irradiance. Cooled and dehumidified air is blown into the greenhouse from below or above the canopy. Cooling below the canopy may induce vertical temperature gradients along the length of the plants. Our first aim was to analyze the effect of the positioning of the inlet of cooled and dehumidified air on the magnitudes of vertical temperature and VPD gradients in the semi-closed greenhouses. The second aim was to investigate the effects of vertical temperature gradients on assimilate production, partitioning, and fruit growth. Tomato crops were grown year-round in four semi-closed greenhouses with cooled and dehumidified air blown into the greenhouses from below or above the crop. Cooling below the canopy induced vertical temperature and VPD gradients. The temperature at the top of the canopy was over 5°C higher than at the bottom, when outside solar radiation was high (solar radiation >250 J cm-2 h-1). Total dry matter production was not affected by the location of the cooling (4.64 and 4.80 kg m-2 with cooling from above and from below, respectively). Percentage dry matter partitioning to the fruits was 74% in both treatments. Average over the whole growing season the fresh fruit weight of the harvested fruits was not affected by the location of cooling (118 vs 112 g fruit-1). However, during summer period the average fresh fruit weight of the harvested fruits in the greenhouse with cooling from below was higher than in the greenhouse with cooling from above (124 vs 115 g fruit-1)