Duration
26h Th, 26h Pr, 4h Proj.
Number of credits
Lecturer
Language(s) of instruction
English language
Organisation and examination
Teaching in the second semester
Schedule
Units courses prerequisite and corequisite
Prerequisite or corequisite units are presented within each program
Learning unit contents
The class describes the different techniques of cooling and low-temperature heating. The class presents the conventional techniques (such as vapor compression refrigeration and heat pump cycles), heat-driven machines, boilers, but also more innovative techniques (such as solar cooling or micro-CHP). Thermal energy storage (sensible and latent) is largely addressed by the class. Passive cooling techniques (aiming at reducing the electrical consumption associated with cooling) are also described.
The lecture gives a detailed description of thermal systems (and components) used through the different cooling and low-temperature heating techniques. In parallel, the lecture presents the modeling and simulation methods of thermal systems and components. The modeling approach is pragmatic: the degree of complexity of the models is adapted to the available information and to the required accuracy according to envisioned applications. This lecture also highlights the "system" approach: it aims at investigating how components of a thermal system interact and how the behavior of the system can be simulated in different working conditions and regimes.
Le class is organized as follows:
- Lecture 1: Volumetric machines in compressor and expander modes: piston
- Lecture 2: Volumetric machines in compressor and expander modes: screw, vanes, root, rolling piston and scroll machines
- Lecture 3: Heat exchangers: classification, modeling, sizing
- Lecture 4: Heat exchangers with mass transfer: cooling and dehumidification coils, cooling towers
- Lecture 5: Sensible and latent (ice and PCM) thermal storage systems
- Lecture 6: Vapor compression refrigeration machines and heat pumps: conventional machines. (chillers, heat pumps), modeling
- Lecture 7: Vapor compression refrigeration machines and heat pumps: advanced cycles (2-stage, vapor injection, cascade), application to commercial refrigeration, cryogenics, and high temperature heat pumps.
- Lecture 8: Heat driven cycles: sorption and ejector cycle machines
- Lecture 9: Boilers
- Lecture 10: Small and micro-CHP systems: internal combustion engines, Stirling, fuel cells, ORC
- Lecture 11: Solar collectors: flat-plate and evacuated tube collectors
- Lecture 11 (alternative): Heat pipes
- Lecture 12: Passive cooling
Learning outcomes of the learning unit
At the end of the lecture, the Student will have a very good knowledge of the different cooling and low-temperature heating techniques (production and storage). He will be able to explain how thermal components and systems used for heating and cooling work. He will be able to compare these thermal components and systems in terms of operating conditions (order of magnitude of temperatures, pressures, flow rates, thermal, mechanical and electrical powers), of achieved performance (efficiency, effectiveness, coefficient of performance) in nominal and part load regimes and of technical maturity.
Also, the Student will be able to model the thermal systems and components introduced in the frame of the lecture and to apply the modeling techniques to other thermal systems that he may encounter in the course of his career of energy engineer.
Prerequisite knowledge and skills
This lecture is in the prolongation of MECA0002-1 (Applied thermodynamics and introduction to thermal machines). It aims at understanding the behavior and modeling thermal machines that operate according to different thermodynamic cycles. The lecture will stress the different irreversibilities (finite temperature heat transfer and pressure losses in heat exchanger, friction in machinery, etc.) that prevent the thermal machine from operating according to theoretical cycles.
Planned learning activities and teaching methods
The lecture will consist in 12 sessions of 4 hours. Each session will comprise a 2 hours lecture followed by a 2 hours session of exercises on computers.
The exercises are given at the beginning of the sessions and are solved by means of EES software (Engineering Equations Solver). The instructor and the student solve together the exercises. The solution is displayed on a screen by means of a projector. At the end of the session, the solutions are sent to the student by email.
The lecture is also illustrated through 1 (or 2) session of laboratory that gives the opportunity to the students to improve the analysis of the performance of real machines and systems. The laboratory sessions will be defined as function of the ongoing research projects at the thermodynamic laboratory. They may deal with the study of a compressor, a boiler, a heat pump, a room air-conditioner, etc. Before the date of the exam, the student will have to provide a report describing the test bench, the achieved measurements, their analysis, the simulation model of the thermal machines developed by the student and its experimental validation.
If enough time is available, a factory visit will be organized.
Mode of delivery (face to face, distance learning, hybrid learning)
Face-to-face
Course materials and recommended or required readings
The class material consists in pdf of powerpoint presentations.
Exam(s) in session
Any session
- In-person
written exam ( open-ended questions )
Written work / report
Further information:
The exam consists in one exam of theory (3 points) and two exercises (7 points per exercise). The theoretical exam (without any class material) is solved on white sheets. The two exercises are solved on a computer (by means of EES software). Students can access the class material for the exercises. The report about the laboratory session will account for 3 points.
The second session exam is organized in an identical way as during the first session.
Work placement(s)
Organisational remarks and main changes to the course
Contacts
Prof. Vincent Lemort
Tel: 04/366 48 01
vincent.lemort@uliege.be