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Design of a 3D print head for mixing additives into cement mixtures
Vícha, Daniel ; Dočkal, Aleš (referee) ; Škaroupka, David (advisor)
The subject of the thesis is the design of a 3D printing head for cement-composite mixtures (concretes). The device enables the addition of the basic component of the mixture by using a liquid solidification accelerator, followed by active homogenization of the mixture and dosing at the printing site. 3D printing of cementitious mixtures often leads to a loss of buckling stability of the printout. Therefore, it is necessary for the printed material to contain additives that accelerate the solidification of the mixture. However, these additives can cause clogging of the hoses when the mixture is pumped into the print head due to premature solidification. Hence, a more suitable solution is to mix these additives in the print head itself. The objective was to develop a 3D print head that allows for homogeneous mixing of the additives in the mixture, thereby eliminating complications associated with pumping. A working prototype of the print head was designed, which consists of a mixing and extrusion chamber. The mixing efficiency of this prototype was verified through numerical simulations using Particleworks. Subsequently, the prototype underwent a mixture experiment without a solidification accelerator to investigate pumpability through the printhead. Based on the numerical simulations, it was determined that the proposed prototype provides sufficient homogeneity of the solidification accelerator with the cement mixture, which should resolve the issues associated with pumping the accelerated mixture. By having a separate mixing chamber, the mixing efficiency can be controlled by adjusting the speed of the motor that drives the mixing shaft. The print head was designed to allow extrusion to be interrupted during print head passes. This was achieved by extruding the mixture into the open space of the chamber using a screw feeder. Therefore, based on the conducted experiments and numerical simulations, it can be concluded that the developed print head has the potential to enhance the quality of 3D printing of cement mixtures and eliminate the problems associated with pumping.
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Control Electronics for Electromagnetic Ball Accelerator
Dočkal, Tomáš ; Harvánek, Michal (referee) ; Král, Jan (advisor)
The goal of this bachelor's thesis was the design and implementation of an electromagnetic accelerator for a steel ball in a closed circular track. Electromagnetic accelerator serves as a demonstrator of particle accelerator functionality and as a game with the aim of engaging students in the study of electrical engineering. The work includes designing the coil using an algorithm in Matlab, which optimizes parameters to achieve maximum magnetic field intensity while considering limited power loss and voltage. The power electronics were designed and the functionality of the circuit concept was verified through simulation. The printed circuit board (PCB) for the power electronics, which also includes the control unit, was designed in KiCad. The system incorporates both passive and active cooling and is equipped with temperature sensors to ensure safe operation. The control part of the system was designed using the ESP-WROOM-32 development module, which allows for remote control and monitoring via a web interface. Optical sensors were designed to enable precise detection of the ball's position and speed. The mechanical part includes the fabrication of the coil frame and the mounts for the optical sensors using 3D printing. The PCB, along with the power supply, was mounted in a casing.
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Accelerator Driven Nuclear Power Plants
Jarchovský, Petr ; Krása,, Antonín (referee) ; Katovský, Karel (advisor)
This bachelor’s thesis deals with utilization of spent nuclear fuel in nuclear power plants of new generation – accelerator driven nuclear power plants and of conversion of this fuel into electrical energy. In the introduction are listed basic physical and theoretical knowledge of nuclear reactors along with their basic division and global distribution. As another point accelerator driven systems are described with their brief development and the basic concept and usage on both the nuclear power plants and transmutation technologies. Some global projects are mentioned here dealing with this system and conduct research. More into detail is point about European projects MYRRHA and ESS, because there are important research facilities worldwide. The next are projects with liquid target as a very promising medium. The last part deals with the calculation of basic parameters of ADS in the MCNPX and its applying.
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A Hardware-acceleration Protocol Design for Demanding Computations over Multiple Cores
Bareš, Jan ; Dvořák, Vojtěch (referee) ; Šťáva, Martin (advisor)
This work deals with design of communication protocol for data transmission between control computer and computing cores implemented on FPGA chips. The purpose of the communication is speeding the performance demanding software algorithms of non-stream data processing by their hardware computation on accelerating system. The work defines a terminology used for protocol design and analyses current solutions of given issue. After that the work designs structure of the accelerating system and communication protocol. In the main part the work describes the implementation of the protocol in VHDL language and the simulation of implemented modules. At the end of the work the aplication of designed solution is presented along with possible extension of this work.
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Binders on the base alumina cements and their properties
Morávková, Jitka ; Cupák, Petr (referee) ; Burianová, Klára (advisor)
The Bachelor Thesis describes chemical and mineralogical structure, as well as alumina cements manufacture and some of their physical and techno-logical properties. It takes accelerators or plasticizers induced changes by search method. An illustrative laboratory measurement of mixture with accel-erator and plasticizer is complementary to theoretical knowledge in fluidity, air permeability and strength of mixture with aluminium silicate cement binder.
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3D printing technology of concrete structures
Roupec, Josef ; Bodnárová, Lenka (referee) ; Hela, Rudolf (advisor)
Subject of Bachelor thesis was the gathering of information about 3D printing using concrete for designing new possible technologies. List of problems connected with material and technological properties in accordance with 3D printing was developed. Based on these findings new modification of fastener was developed. This fastener works with reaction time of few minutes. Testing was conducted using calorimetric measurements. Findings confirmed the usability of fastener in a cement paste. These results led to design of technology able to use the fastener. This technology was designed for as fast printing as technologically and materially possible in controlled environment. Furthermore, two new technologies for printing of extremely lightweight constructions from UHPC using 3D printing. First uses extrusion technique with screw feeder. Second method is based on binder jetting technology.
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A Hardware-acceleration Protocol Design for Demanding Computations over Multiple Cores
Bareš, Jan ; Dvořák, Vojtěch (referee) ; Šťáva, Martin (advisor)
This work deals with design of communication protocol for data transmission between control computer and computing cores implemented on FPGA chips. The purpose of the communication is speeding the performance demanding software algorithms of non-stream data processing by their hardware computation on accelerating system. The work defines a terminology used for protocol design and analyses current solutions of given issue. After that the work designs structure of the accelerating system and communication protocol. In the main part the work describes the implementation of the protocol in VHDL language and the simulation of implemented modules. At the end of the work the aplication of designed solution is presented along with possible extension of this work.
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Accelerator Driven Nuclear Power Plants
Jarchovský, Petr ; Krása,, Antonín (referee) ; Katovský, Karel (advisor)
This bachelor’s thesis deals with utilization of spent nuclear fuel in nuclear power plants of new generation – accelerator driven nuclear power plants and of conversion of this fuel into electrical energy. In the introduction are listed basic physical and theoretical knowledge of nuclear reactors along with their basic division and global distribution. As another point accelerator driven systems are described with their brief development and the basic concept and usage on both the nuclear power plants and transmutation technologies. Some global projects are mentioned here dealing with this system and conduct research. More into detail is point about European projects MYRRHA and ESS, because there are important research facilities worldwide. The next are projects with liquid target as a very promising medium. The last part deals with the calculation of basic parameters of ADS in the MCNPX and its applying.
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Binders on the base alumina cements and their properties
Morávková, Jitka ; Cupák, Petr (referee) ; Burianová, Klára (advisor)
The Bachelor Thesis describes chemical and mineralogical structure, as well as alumina cements manufacture and some of their physical and techno-logical properties. It takes accelerators or plasticizers induced changes by search method. An illustrative laboratory measurement of mixture with accel-erator and plasticizer is complementary to theoretical knowledge in fluidity, air permeability and strength of mixture with aluminium silicate cement binder.
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