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Temperature Profile in Reflow Soldering and Influence of Different PCBś and ComponentsThermal Capacities
Procházka, Martin ; Špinka, Jiří (referee) ; Starý, Jiří (advisor)
This thesis mainly deals with the prediction of temperature on the components and the PCB during reflow soldering. The theoretical part describes the particular solder reflow process, types of heat transfer and temperature profiles. The practical part is divided into forecasting temperatures if the conveyor is stopped and the temperature predictions when the conveyor is in motion. In both parts of the measured temperature is compared with the predicted temperatures, which show the success rate of prediction. The last part of this work is part of the simulation, which helps in proper understanding of the issues discussed.
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Non-contact Temperature Measurement
Lata, Miroslav ; Janečka, Jan (referee) ; Vdoleček, František (advisor)
The object of this bachelor thesis was to create a study of development non-contact temperature measurement and show methods of measurement in infra-red radiation area. The beginning of this work is focused on major notions and definitions necessary to introduce non-contact temperature measurement topic. Other interest of this work was to mention possible error rate of measurement, it’s reasons then name some ways of calibration of a measuring equipment with it’s reasons too. Last part of this thesis was focused on a practical using of these measuring devices.
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Methodology of temperature measurement behind jet engine
Koutný, Martin ; Koštial, Rostislav (referee) ; Matějů, Jiří (advisor)
This thesis is focused on temperature measurement behind jet engine. The theoretical part introduces chosen ways of temperature measurement. The practical part is divided into design (and later assembly) of the measuring stand, methodology of measurement and the measurement itself. The main outcome are heat maps gained by measuring temperatures behind TJ – 42 jet engine.
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Emisivity and its Impact on the Heat Conductivity
Gančev, Jan ; Hejátková, Edita (referee) ; Szendiuch, Ivan (advisor)
This work deals with the issue of emissivity and its impact on the heat dissipation.The first part describes the basics of thermal management, the issue of emissivity and its measurement. In the second, experimental part, are dedicated the emissivity values of examined specimens. These values are then used as initial conditions for the thermal simulation. In the last part are compared the measured results and the simulated results and is evaluated the impact of emissivity for the heat dissipation.
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Analysis of locally modified surfaces for selective growth of cobalt
Krajňák, Tomáš ; Bábor, Petr (referee) ; Čechal, Jan (advisor)
In this thesis the chemical composition of silicon substrates locally modified by focused gallium ion beam by X-ray photoelectron spectroscopy is determined. In order to determine the influence of focused ion beam, the sample comprising sputtered square areas with nominal depths in range of 1 to 10 nm was prepared. Next, the sample was heated to elevated temperatures (500 - 700 °C) to reveal changes in the sputtered areas induced by annealing. In this work by X-ray photoelectron spectrometer Kratos Supra and electron microscope Tescan LYRA3 with focused ion beam were used. From the measured spectra of the Si 2p and Ga 2p3/2 peaks measured as a function of nominal sputtering depth and annealing temperature the following main observations were obtained. First, there is the additional peak component in the Si 2p peak, which can be assigned to the amorphous silicon. The second important finding is that gallium can be removed from near surface volume by annealing at temperatures beyond 700 °C.
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QFN Packages Soldering and Technology Procedures
Jakub, Miroslav ; Brno, Petr Martinec, HONEYWELL (referee) ; Starý, Jiří (advisor)
This master´s thesis deals with QFN packages soldering and technology procedures optimization. The aim of theoretical part is description of QFN packages, their assembly and reflow soldering on PCB in HONEYWELL. The aim of the practical part is to propose a method of measuring temperature and optimizing the thermal profiles of selected PCB with QFN packages by using convection (HONEYWELL) and infrared (BUT) reflow ovens. Comparison and evaluation of thermal profiles for 3 production PCBś with QFN packages using solder paste AIM NC257-2 were realised. The main part of master´s thesis are appearance evaluation of solder joints, preparing microsection and measuring intermetallic layers thickness by using the optical and the scanning electron microscopes, analysation and study of QFN defects created during soldering proces. These tests were performed with 2 production PCB´s. Optimization of SPI and soldering technology procedures where were analyzed QFN packages were processed on one type of PCB. Interesting part of this diplomma thesis is creating of the 3D heat transfer model of QFN package during the reflow soldering in SolidWorks.
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Methods of Identification of Vehicle Brake System Temperatures
Jaroň, Dominik ; Fojtášek, Jan (referee) ; Hejtmánek, Petr (advisor)
The work is aimed at measuring temperature of main parts of vehicle braking system. The first part is theoretical background for temperature measuring by thermocouples, IR pyrometers and paint pyrometers. There are also introduced devices and products, which are nowadays available to buy and which can be used for measuring. In the second part of this thesis there are shown methods of measuring by mentioned thermometers and evaluation of their pros and cons.
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Solar Radiation Measurements
Chvátal, Michal ; Pikula, Stanislav (referee) ; Beneš, Petr (advisor)
The Bachelor‘s thesis discusses design and verification of an inexpensive method for indicative measurement of direct and diffused solar radiation. The reason for the measurement of solar radiation is the estimate the heat gain of buildings. In this paper the difference between thermoelectric generator and cooler is described. There is also described how to choose a suitable module for solar radiation measurement. The design of the measuring circuit and the construction of sensor are also described. Eventually the measured values are compared with the values from the commercial pyranometer SG420.
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Microsolder controlled by microprocessor
Stavělík, Jiří ; Petyovský, Petr (referee) ; Macho, Tomáš (advisor)
This thesis describes circuit design and realization of the power and control system, which can hold constant temperature of solder tip. Control system is based on microcontroller Atmega328 of company Atmel, part of the work is the implementation and debugging control software. This solution allows to enter temperature by rotary encoder and to show the real temperature on LCD displey. This hardware also detects disconnection of solder tip, acoustic signals when the required temperature is reached and it holds last set temperature.
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Thermocouple simulator
Nermut, Martin ; Michalec, Jaroslav (referee) ; Klusáček, Stanislav (advisor)
NERMUT, M. Thermocouple simulator. Brno: Brno University of Technology, Faculty of Eletrical Engineering and Communication. 2009. 62 s. Supervisor Ing. Stanislav Klusáček. Consultant Ing. Miroslav Krupa, - IDC Brno, Honeywell s.r.o. The aim of the thesis is design and realization of handheld thermocouple simulator, suitable both for laboratory and plant use. Manual or remote control via RS232 are possible. Special attention is focused on universality, easy and safety use (galvanic isolation), properly cold junction compensation, easy calibration of non-linearity. Sponsor: IDC Honeywell, Brno, Czech Republic Basic literature: - OMEGA Temperature Handbook) - Datasheets of OMEGA instruments (www.omega.com) - Datasheets of other vendor instruments (www) - Isotech Traceable Book – Temperature Calibrabration (www.isotech.co.uk) - BELZA J., Buld-in Li-ion accu charger (www.belza.cz) Appendixs: - User manual - Schematic - Calibration data - CD (source code)
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