Electrical Heat Technology
FEKT-LELTAcad. year: 2017/2018
Opening part of the subject is devoted to the calorimetry and the heat transfer. Student deepens his knowledge in this theory and uses these knowledges for solving problems in numerical exercises. The main part is focused on the individual type of electric heatings. It's resistant heating, electric arc heating, inductive, dielectric and microwave heating. Modern conceptions are represented by the plasma, laser, electron and infrared heating. Student gets to know the physical nature and theory of individual heatings and the basic electrothermal applications in the industrial area.The higher attention is devoted to the resistance crucible furnace and its design and electric arc furnace and settings of optimal parameters of furnace working.
Learning outcomes of the course unit
Graduate from this subject is able to:
- define and describe the basic quantity of the electrothermal technology, heat transfer, calorimetry and calculate them,
- design and calculate the basic parameters of electrical heating elements of electrical resistance crucial furnace,
- enumerate the types of electrothermal heatings and explain their physical nature,
- enumerate and describe the technical applications of electrothermal heatings.
The subject knowledge on the Bachelor´s degree level is requested.
Recommended optional programme components
Recommended or required reading
Baxant P., Drápela J., Lázničková I.: Elektrotepelná technika. (CS)
Baxant P., Drápela J., Lázničková I.: Elektrotepelná technika. Laboratorní cvičení. (CS)
Lázničková I.: Elektrotepelná technika. Sbírka příkladů. Brno, 2013. (CS)
Hradílek Z., Lázničková I., Král V.: Elektrotepelná technika, ČVUT v Praze, Praha 2011, http://www.powerwiki.cz/wiki/Vyuka (CS)
Rada, Zd. Elektrotepelná technika, SNTL Praha, 1995 (CS)
Planned learning activities and teaching methods
Teaching methods depend on the type of course unit as specified in the article 7 of BUT Rules for Studies and Examinations.
Teaching methods include lectures, numerical exercises and practical laboratories. Course is taking advantage of e-learning (Moodle) system.
There are continuous tests in the numerical exercises.
Assesment methods and criteria linked to learning outcomes
During the term the students can obtain max. 40 points - final test, 2 individual works, laboratory reports.
Examination (max. 60 points) includes written part (test questions + examples) and oral part.
Requirements for successful completion of this subject are determined by a annual regulation of the lecturer.
Language of instruction
1. Basic terms, units, analogy between electric and temperature field, calorimetry, calculations.
2. Heat transfer, conduction, convection, radiation, compound cases of heat transfer, calculations.
3. Measuring of temperature in electrothermal technology. mechanical and electrical thermometers.
4. Electrical heating elements, materials of electrical heating elements, calculation of basic parameters of heating elements.
5. Resistance heating, direct and indirect heating. Electrical rasistance furnaces.
6. Design of resistance crucible furnace for melting of aluminium.
7. Electric arc heating, direct arc, alternating arc, stabilization of arc, static and dynamic characteristics of arc.
8. Electric arc furnace, connection to net, furnace transformer, choking coil, electrodes, circle diagram of electrical arc furnace.
9. Plasma heting, plasma, basic processes in plasma, plasma heater, melting plasma furnace.
10. Induction heating, induction crucible and canal furnace, screening, pinch efect.
11. Induction heating, basic theory electromagnetig field, Poyinting radiant vector.
12. Dielectric heating, polarisation, loss number, microwave heating, magnetron.
13. Special electrothermal hetings - laser heating, electron heating, infrared heating, resonator, electron gun.
Calorimetry, heat transfer and design of resistance crucible furnace are solved in concrete problems.
1. Measurement of emissivity of non transparent bodies.
2. Measurement of heat conductivity of material.
3. Measurement of characteristic quantities of resistance materials.
Course content is to apprise students of basic theory of basic and special types of the electrothermal heatings and their technical applications.
Specification of controlled education, way of implementation and compensation for absences
The content and forms of instruction in the evaluated course are specified by a regulation issued by the lecturer responsible for the course and updated for every academic year.
Labs are compulsory; correctly excused absence can be replaced by arrangement with the teacher.