THERMAL SYSTEMS

Academic Year 2023/2024 - Teacher: ARTURO PAGANO

Expected Learning Outcomes

The goal of the course is to provide the students with a detailed theoretical and application-oriented knowledge, enabling them to design and dimension the main thermal plants, specifically in the following contexts:
- thermal plants and technologies for steam production and for heat generation and distribution, for civil and industrial applications and for power generation;
- refrigeration plants and technologies, for civil and industrial applications;
- analysis and characterization of the thermal energy needs for the heating and cooling of buildings;
- heating, ventilation and air conditioning sytems (HVAC sytems) for buildings.

Course Structure

Lectures will be given in classroom or, if conditions would require it, they will be available on-line or in mixed modality.

Students must attend at least 70% of the course lectures. It is mandatory the subscription to the course on the webpage on studium.unict.it.

Required Prerequisites

Contents of the courses of applied thermodynamics, heat transfer and fluid machines design.

Detailed Course Content

1. Review of the contents of the course of Applied Thermodynamics and Heat Transfer (Fisica Tecnica), mainly on thermodynamic cycles for power generation and for cooling and on heat exchangers.
2. Fuels, combustion process and combustion products: thermal energy, exhaust flue gases, ashes and main pollutants.
3. Furnaces and heat generators for industrial applications and for power generation. Technologies and combustion equipment for heat generators.
4. Steam compression and absorption refrigeration systems and heat pumps for civil and industrial uses. Notes on cryogenic plants.
5. Principles of cogeneration.
6. Characteristics of the building envelope and related regulatory prescriptions concerning the building envelope and its heating system. Ventilation of confined spaces and principles of human comfort.
7. Heating systems and HVAC (Heat, Ventilation and Air Conditioning) systems for civil environments: principles and sizing criteria.

Textbook Information

Textbook 1 - Boilers for Power and Process, K. Rayaprolu, CRC Press - Taylor & Francis, 2009

Textbook 2 - Thermal Power Plant - Design and Operaration, D.K. Sarkar - Elsevier, 2015

Textbook 3 - Aria Umida - Climatizzazione ed involucro edilizio, L. Bellia, P. Mazzei, F. Minichello, D. Palma - Liguori Editore, 2006

Textbook 4 - Refrigeration, air conditioning and heat pumps, G.F. Hundy, A.R. Trott, T.C. Welch, ed. Butterworth-Heinemann (Elsevier).

Textbook 5 - La ventilazione per una migliore qualità dell’aria, A. Magrini, M. Ozel-Ballot, 2ed - EPC libri, 2005.

Textbook 6 - Benessere termico e qualità dell'aria, G. Moncada Lo Giudice, M. Coppi - Ed. Masson 1997.

Course Planning

	Subjects	Text References
1	Boiler Technology: Boiler classification criteria and design variables; general structure and energy analysis of a boiler. Schematic of the furnace-boiler set-up.	Text 1 and 2
2	Two-phase flows and the Nukiyama curve for pool and flow boiling: Departure from Nucleate Boiling and Critical Heat Flux. Evaluation of heat transfer coefficients.	Text 1 and 2, course material
3	Optimal and safe boiler operations. Natural and forced circulation schemes. Subcritical and supercritical boilers.	Text 1 and 2, course material
4	Water treatments for boilers: feedwater treatments and boiler water conditioning.	Text 1 and 2
5	Fuel constituents: Proximate Analysis and Ultimate Analysis. Fundamental phases of the combustion process for coals. Evaluation of stoichiometr combustion air and of excess air. Flue gas analysis.	Text 1, course material
6	Fuels classification and relevant characteristics of coals, oil, natural gas, waste and derived fuels, biomasses. Fuel ash and related issues: erosion, slagging and fouling, corrosion. Ash related design criteria for furnaces and boilers.	Text 1, course material
7	Technologies and firing equipment for boiler furnaces 1/2: Stocker-fired furnaces for boilers - mass burning stockers and spreader stockers; burners for oil and gas fired boilers and related furnace schemes; design criteria for Low-NOx burners; duct burners for Heat Recovery Steam Generators, HRSGs.	Text 1 and 2
8	Technologies and firing equipment for boiler furnaces 2/2: Pulverized Fuel boilers and related boiler structures, milling technology; Fluidized Bed Combustion technologies and issues related to inbed desulfurization; Bubbling Fluidized Bed Combustors, BFBCs; Circulating Fluidized Bed Combustors, CFBCs, cyclone technologies and related boiler design schemes.	Text 1 and 2
9	Optimal design of the boiler heating surfaces and related fuel and energy recovery issues. Dust collecting equipment and flue gas DeNOx and DeSOx treatments.	Text 1, course material
10	Refrigeration systems and Heat Pumps: fundamental thermodinamic cycles and advanced solutions	Text 4, Course material
11	Refrigeration systems and Heat Pumps: technologies and main components	Text 4, Course material
12	Energy analysisis of buildings. Transmittance evaluation and measurement, limitations imposed by the Italian legislation concerning: a) opaque elements; b) thermal bridges; c) transparent elements.	Course material, CENED tables, Text 3
13	Energy analysis of the building envelope 2/2 - Dynamical behaviour of the building envelope and related performances; Strategies for controlling solar radiation; Thermal-hygrometric perfomances.	Course material, Text 3
14	Legislative framework for Indoor Air Quality, IAQ . Natural and mechanical ventilation. Thermal comfort analysis and related building design issues.	Course material, Text 5, Text 6
15	HVAC systems: thermodynamics of humid air and psycrometric diagrams	Course material, Text 3
16	HVAC systems: basic components and related processes; HVAC system classification	Course material, Text 3
17	HVAC systems: total air HVAC systems	Course material, Text 3
18	HVAC systems: primary-secondary air mixed HVAC systems	Course material, Text 3
19	HVAC systems: design test and exercises	Course material
20	Technologies for air conditioning: single and multi split autonomous air conditioner	Course material, Text 3
21	Technologies for air conditioning: air distribution network, air grids and diffusers, water distribution network, fancoils	Course material
22	Domestic heating systems: types of heaters, distribution network	Course material
23	Presentation and use of a software tool for the energy analysis and classification of the performance of the building envelope and thermal plants.	Course material

Learning Assessment

Learning Assessment Procedures

The exam consists of two parts: a structured written test and an oral discussion. The admission to the oral exam is achieved only through the assignment of a sufficient score (18/30) to the written test. Both written and oral exam aim to verify the student's ability to discuss and argue the theoretical aspects of the discipline and to solve practical and/or design problems. During the oral exam, the student will be required to discuss a report produced during the laboratorial activities carried out during the course with a thermo-technical design software.

The written part of the exam is organised in theoretical questions, structured in order to allow a synthetic answer, and in practical calculation and/or design problems of components and thermotechnical systems.

To guarantee equal opportunities and in compliance with the laws in force, students enrolled in CInAP can agree with the teacher any compensatory and/or dispensative measures, based on the educational objectives and specific needs. It is also possible to contact the CInAP reference teacher of DICAR.

Examples of frequently asked questions and / or exercises

- Describe the general structure of a boiler or of the furnace-boiler set-up

- Discuss the terms accounted in the energy balance equation of a boiler

- Discuss the Nukiyama curve for pool or flow boiling

- Schematize the main natural and forced circulation schemes for boilers

- Discuss the fundamental phases of coal combustion

- Fuel ash and related issues: erosion, slagging and fouling, corrosion

- Ash related design criteria for furnaces and boilers

- Detailed description of the main firing technologies (stocker-fired, burners for oil, gas and pulverized coal; bubbling/circulating fluidized bed combustors; duct burners for heat recovery steam generators)

- Advanced cycles and related plant schemes for refrigerators and heat pumps

- Technologies and main components for refrigeration and heat pumps

- Energy analysisis and related legislative issues for the design of building envelopes: static transmittance of opaque elements, thermal bridges and transparent elements; dynamical behaviour of the envelope components

- Indoor air quality, indoor thermal comfort and related design issues

- HVAC systems: basic components and related processes; HVAC system classification

- HVAC systems: calculation of total air HVAC systems and of primary-secondary air mixed HVAC systems

Degree Course in

Mechanical Engineering