The main aim of this diploma thesis is design and calculation of steam condensing turbine with given parameters. In the first part is made calculation of heat balance scheme, which contains high and low pressure regeneration and turbine with total of 5 unregulated steam extraction. It is followed by calculation of regulating stage with impulse blading and calculation of stage part of turbine with reaction blades with total of 27 stages divided to 7 cones. Designes of regulating stage and stage part were checked by calculation of tensile and bending stress. In next parts are calculations of compensating piston and turbine seal system, design of radial and thrust bearings and in the last chapter is shown consumption characteristics of turbine. The designed turbine after optimization at nominal condition has power of 55013,02 kW with thermodynamic efficiency of 83,06 %. The reheat factor of turbine is 1,063. The diploma thesis is supplemented by a conceptual sectional drawing of turbine.

With the rapid development of concrete 3D printing for construction projects, it is crucial to produce sustainable 3D-printed cementitious composites that meet the required fresh and hardened properties. This study investigates the application of cellulose-based nanomaterials (CN) (i.e., abundant natural polymers) that can improve the mechanical properties of cement-based materials – in 3D-printed cementitious composites of ordinary portland cement (OPC) and alkali-activated materials (AAMs). A combination of low calcium fly ash and ground granulated blast-furnace slag was used as the precursor in AAM systems. This work examines the 3D-printed mixtures with varying binders and mixture proportions and with different dosages of cellulose-based nanomaterial known as cellulose nanocrystals (CNC) to optimize the formulation for the production of sustainable high-performance 3D-printed elements. A suite of experimental techniques was applied to study the impact of CNC on the fresh and hardened properties of the 3D-printed samples. The buildability of the alkali-activated mixtures was improved by increasing the CNC content, suggesting that the CNC performs as a viscosity-modifying agent in AAMs. The inclusion of CNCs up to 1.00% (by volume of the binder) improves the overall mechanical performance and reduces the porosity of 3D-printed OPC and heat-cured AAM samples. Further, the addition of CNC (up to 0.30%) in sealed-cured AAM samples improves their flexural strength due to the crack-bridging mechanism of CNCs. The addition of CNC densifies the microstructure of OPC samples by increasing the degree of hydration, however, no significant impact on the microstructure of AAMs is noticed. The OPC sample with CNC has approximately 25% increase in the degree of hydration at inner depths which can be attributed to the internal curing potential of CNC materials. The initial water absorption rate of heat-cured AAM samples is lower than the sealed-cured AAM samples and comparable to the OPC system. The developed printable “alkali-activated-CNC” composites can provide an overall reduction in the environmental impacts of the 3D-printed cementitious composites by eliminating/reducing the need for different chemical admixtures to improve 3D-printed material consistency and stability, and replacing 100% of portland cement with fly ash and slag. / Civil Engineering

This diploma thesis deals with the thermodynamic design of a backpressure steam turbine. The mass flow of steam through the turbine is determined based on the required heat output, which is transferred in a heat exchanger at the turbine outlet. The governing stage of the turbine is in form of an impulse stage, with optimization of degree of reaction included. During the optimization, a suitable rotor blade was chosen as well as its size. The governing stage is followed by fifteen stages of reaction blading with the stage loading coefficient in the range of 2,75 to 2,80. The governing stage and the reaction blading both meet the mechanical strength requirements. Balancing piston, sealing system and bearings are also designed. Finally, a turbine characteristic is created as well as a longitudinal section. The designed turbine has a speed of 10 000 rpm. While supplying the required heat output, it has a terminal power output of 5 863,4 kW and a thermodynamic efficiency of 84,69 %.