Unit
- Course
- Mechanical engineering
- Study-unit Code
- A002387
- Curriculum
- Costruzioni
- Teacher
- Cinzia Buratti
- CFU
- 10
- Course Regulation
- Coorte 2022
- Offered
- 2022/23
- Type of study-unit
- Opzionale (Optional)
- Type of learning activities
- Attività formativa integrata
MODULE A
| Code | GP004963 |
|---|---|
| CFU | 5 |
| Teacher | Giorgio Baldinelli |
| Teachers |
|
| Hours |
|
| Learning activities | Affine/integrativa |
| Area | Attività formative affini o integrative |
| Academic discipline | ING-IND/10 |
| Type of study-unit | Opzionale (Optional) |
| Language of instruction | Italian |
| Contents | Complements of heat transfer and fluid flow applied to the problems of mechanical engineering. Thermal fluid dynamics and computational models for the dispersion of pollutants in the atmosphere. Thermal fluid analysis of buildings envelope: dynamic thermal characteristics, heat transfer matrix, practical examples. |
| Reference texts | G. Guglielmini, C. Pisoni, Elementi di trasmissione del calore, Ed. Veschi Lecture notes will be distributed by the teacher. |
| Educational objectives | The primary goal of the module consists of providing students with tools to solve advanced heat transfer issues. The laboratory phase is aimed to make visible the theoretical aspects treated in class lectures, both in experimental terms and as far as the use of thermal-fluid-dynamic calculations. In addition, through the direct (optional) involvement of students in exposing topics in the classroom, it is intended to make them facing the intrinsic difficulties of public speaking, indicating methods for its improvement. |
| Prerequisites | The student must know the basics of mathematical analysis, with particular reference to differential and integral calculation. Essential prerequisites are also the basics of thermodynamics. |
| Teaching methods | The course is organized with classroom on all treated subjects, as well as laboratory exercises for observing the conduction, convection and irradiation phenomena. The study of computational analysis is supported by application examples through a commercial code. There is also the possibility, optional, for all students to take a lecture to the classroom on a topic of in-depth study. |
| Other information | Attendance to the classes is optional but strongly advised. |
| Learning verification modality | The exam includes a written test and an oral exam. The written exam, which lasts an hour and a half, is the solution of an issue on a topic related to module A (fluid-dynamics) and a problem related to the module B (HVAC Plants) regarding the design of parts of a HVAC plant. The test is intended to verify: i) the ability to understand the problems proposed during the course, ii) the ability to correctly apply the theoretical knowledge, iii) the ability to propose independently different design modes; iv) the ability to effectively communicate in writing. The oral tests, one for each module, consist of a discussion of no longer than 45 minutes each aimed to determine: i) the level of theoretical and methodological knowledge of the contents of the two modules; ii) the level of expertise in exposing possible technical solutions to problems of sizing of components and systems, iii) the independence of judgment in proposing the most appropriate approach for each scope. The oral examinations also aims to verify the student's ability to expose issues proposed by the Commission with property of language, to support a dialectical relationship during discussion and summarize the results of application of the theories studied. The evaluation of the written test is carried out by the Commission, giving up to 15 points to the topic of the module A and up to 15 points to the problem of the module B; the final evaluation is carried out by the Commission by averaging the results of the written test and two oral exams with the following weights: written test weight = 1/3; oral Module A weight = 1/3; oral Module B weight = 1/3. |
| Extended program | Conduction Thermophysical properties; non-stationary cases ; approximation of the thin object; nonlinear problems: conductivity integral; transient in non-uniform temperature systems; fins. Radiation Radiation heat transfer; radiosity method. Characters of convection Navier-Stokes equations, energy equation in fluids, a dimensionless form of convection equations, boundary layer approximation; mechanical and thermal boundary layers, boundary layer equations, flat plate similarities solutions, the boundary layer in non-planar geometries: separation, laminar flow in pipes, losses calculation; laminar convection in internal flows, laminar natural convection. Characters of turbulence Transition to turbulence; structure of turbulence, Reynolds stress, mixing length; velocity profiles, pressure drop in turbulent flows; rough pipes, turbulent thermal diffusivity; Reynolds analogy , heat exchange relations for interior flows. Condensation and boiling Film condensation, the effects of turbulence; correlations for film condensation, drops condensation; effect of non-condensable gases. Nukiyama curves; overheating; bubble growth; critical flow; forced convection boiling; correlations for boiling in forced convection. Heat exchangers Methods of MLTD and efficiency; multiple stages heat exchangers, heat exchangers typologies . Thermal Fluid Dynamics Computational Finite differences method, finite differences methods in conduction heat transfer; application of finite differences in conduction problems, the finite elements method; equations for the finite elements method in steady-state conduction; application of the finite elements method to a case of non-stationary conduction, the finite elements method in non-stationary regimes, integration of the non-stationary finite elements equations. Applications and case studies. Mathematical models for calculating the dispersion of pollutants into the atmosphere Classes of atmospheric stability, vertical temperature gradients. The phenomenon of temperature inversion. General criteria for the models choice of pollutants diffusion in the atmosphere. Gaussian models. Applications and case studies. |
MODULE B
| Code | GP004964 |
|---|---|
| CFU | 5 |
| Teacher | Cinzia Buratti |
| Teachers |
|
| Hours |
|
| Learning activities | Affine/integrativa |
| Area | Attività formative affini o integrative |
| Academic discipline | ING-IND/10 |
| Type of study-unit | Opzionale (Optional) |
| Language of instruction | Italian |
| Contents | Thermoigrometrical comfort. Air quality and buildings ventilation. Thermal loads. Italian Laws and Thechnical Standards. Plants classification: design criteria for air distribution, air treatment, fancoils, water distribution, heat generators and refrigerating machines. Heat Pumps. Plants regulation. Plants for fire protection. |
| Reference texts | - C. Buratti: Impianti di Climatizzazione e Condizionamento, Morlacchi Editore, 2015. - Slides provided by the teacher. |
| Educational objectives | The aim is to provide students with knowledge and competence needed for HVAC systems design. Il shows the sizing criterions for the main components of a plant: air outlets, air distribution system, air treatment unit, heaters and coolers, water distribution system, heat generators, chillers. To this aim at the beginning knowledges about thermal comfort, thermal loads calculation, Italian Laws and Thechnical Standards, and HVAC plants classification are provided. |
| Prerequisites | In order to be able to understand and apply the majority of the techniques described within the Course, students must have notions of mathematical analysis such as techniques of derivation and integration of functions of several variables, differential equations. Furthermore they must have successfully passed the Applied Thermodynamics and Heat Transfer exam and they have to be able to evaluate heat transfer in building walls and the performance of thermal engines. Finally they have to use psychrometric chart for energy calculations. Knowledge of these techniques represemnts a mandatory prerequisite for students planning to follow this course with profit. |
| Teaching methods | The course is organized as follows: - Lectures on all the subjects of the program; - Exercises in classroom as training for the written test; - Practice execises by means of laboratory visits or by means of instrumentations and software in classroom; - At the end of the course visit of a HVAC plant in a real building and explaination of its operation mode by the designer or the manager. |
| Other information | Attendance to the classes is optional but strongly advised. |
| Learning verification modality | The exam includes a written test and an oral exam. The written exam, which lasts an hour and a half, is the solution of an issue on a topic related to module A (fluid-dynamics) and a problem related to the module B (HVAC Plants) regarding the design of parts of a HVAC plant. The test is intended to verify: i) the ability to understand the problems proposed during the course, ii) the ability to correctly apply the theoretical knowledge, iii) the ability to propose independently different design modes; iv) the ability to effectively communicate in writing. The oral tests, one for each module, consist of a discussion of no longer than 45 minutes each aimed to determine: i) the level of theoretical and methodological knowledge of the contents of the two modules; ii) the level of expertise in exposing possible technical solutions to problems of sizing of components and systems, iii) the independence of judgment in proposing the most appropriate approach for each scope. The oral examinations also aims to verify the student's ability to expose issues proposed by the Commission with property of language, to support a dialectical relationship during discussion and summarize the results of application of the theories studied. The evaluation of the written test is carried out by the Commission, giving up to 15 points to the topic of the module A and up to 15 points to the problem of the module B; the final evaluation is carried out by the Commission by averaging the results of the written test and two oral exams with the following weights: written test weight = 1/3; oral Module A weight = 1/3; oral Module B weight = 1/3. |
| Extended program | Thermoigrometrical comfort: comfort indexes, influence of temperature, relative humidity, air velocity, etc.. Local iscomfort: radiant asimmetry, draft risk, thermal gradient, ecc. Comfort charts. Air quality and buildings ventilation. Measurements. Thermal loads. Italian Laws and Thechnical Standards. HVAC (Heating Ventilating and Air Conditioning) Plants classification: design criteria for air distribution, air treatment, fancoils, water distribution, heat generators and refrigerating machines. Heat pumps. Plants regulation. Plants for fire protection. |