635-3005/01 – Heat exchangers (VT)
| Gurantor department | Department of Thermal Engineering | Credits | 6 |
| Subject guarantor | prof. Ing. Miroslav Příhoda, CSc. | Subject version guarantor | prof. Ing. Miroslav Příhoda, CSc. |
| Study level | undergraduate or graduate | Requirement | Choice-compulsory |
| Year | 1 | Semester | summer |
| | Study language | Czech |
| Year of introduction | 2014/2015 | Year of cancellation | 2020/2021 |
| Intended for the faculties | FMT | Intended for study types | Follow-up Master |
Subject aims expressed by acquired skills and competences
Student will be able:
- to categorize heat exchangers
- to solve power and hydraulic losses or recuperators and regenerators
- to illustrate ways of usage of thermal efficiency in determination of heat transfer surface of recuperator
- to determine conditions of application of recuperative and regenerative heat exchangers
Teaching methods
Lectures
Tutorials
Project work
Summary
Significance of heat exchangers. Recuperators: temperature profile across the exchanger heat transfer area, mean temperature difference, heat transfer coefficient, heat transfer rate, temperature of heat transfer surface, heat transfer effectiveness of parallel flow and counter-flow, hydraulic calculation. Metal and ceramic recuperator types. Heat pipes: working fluids, temperature distributions, heat transfer rate. Regenerators: Thermal calculation. Heat transfer quantity. Heat transfer coefficient. Hydraulic calculation. Regenerator types.
Compulsory literature:
[1] LIENHARD IV, J. H., LIENHARD V, J. H. A Heat Transfer Textbook. 4th ed. Cambridge: Phlogiston Press, 2012. http://web.mit.edu/lienhard/www/ahtt.html (Chapter 3).
Recommended literature:
Way of continuous check of knowledge in the course of semester
Written test
E-learning
http://katedry.fmmi.vsb.cz/635/;
There is a continuous expansion of e-learning elements into teaching.
Other requirements
Elaboration of the projekt.
Prerequisities
Co-requisities
Subject has no co-requisities.
Subject syllabus:
1. Classification of heat exchangers. The importance of heat exchangers, energy saving, fuel savings, the degree of recuperation, increasing combustion temperature, increase performance aggregate.
2. Thermal calculation of recuperator. The differential equation for the relationship between medium temperature and the size heat transfer surface. Solving equations for various cases boundary conditions.
3. Dependence of temperature difference between the hot and cold streams on the size of the heat transfer surface. Calculation of the mean temperature difference.
4. Heat transfer coefficient for the ceramic and metal recuperators. Influence of heat transfer coefficients on the overall heat transfer coefficient
5. Heat rate of recuperator. Temperature heat transfer surfaces in the consideration or neglecting the thermal resistence of heat transfer surfaces, a criteria expression.
6. The definition of heat exchanger effectiveness. Determination of heat exchanger effectiveness for the parallel and counterflow cases for different ratios between total heat capacities.
7. Hydraulic calculation. Pressure loss by friction, local, geometric. Pressure losses resulting from non-isothermal flow mediums.
8. Types of metal, ceramic and plastic heat exchangers. Operating conditions of heat exchangers.
9. Heat pipes: the working fluid, process temperature and radial heat flow.
10. Regenerators - Thermal calculation. The amount of heat transmitted. The coefficient of heat transfer. Hydraulic calculation. Pressure losses. Types of regenerators.
Conditions for subject completion
Occurrence in study plans
Occurrence in special blocks
Assessment of instruction