Learning objectives
knowledge and ability to understand
Through the lectures given during the course, the student will acquire the knowledge necessary to understand the operation of fluid machines, boilers and internal combustion engines.
Ability to apply knowledge and understanding
Through classroom exercises on some topics, the students learn how to apply the acquired knowledge and the approach to follow in the design of the presented machines.
Evaluation autonomy
The student should be able to understand and evaluate the operation of the studied fluid machines critically, and he should be able to evaluate which machine is most suitable for the application required.
Communication skills
Through the frontal lessons the student acquires the specific vocabulary concerning the fluid machines. It is expected that at the end of the course the student will be able to convey the main contents of the course, such as ideas, engineering issues and related solutions, in oral and written form.
Learning ability
The student who has attended the course will be able to deepen his knowledge through the autonomous consultation of specialized texts, scientific or dissemination journals, even outside lecture topics, in order to effectively address the inclusion in the labour market or undertake further training paths.
Prerequisites
Fluid machine and energy conversion systems (bachelor degree level)
Course unit content
The course aims to provide students with the following knowledge:
the fundamental concepts and the relative equations inherent the motion of compressible and incompressible fluids;
the architecture, the functional and performance characteristics of the main volumetric and dynamic fluid machines;
architecture and main characteristics of boilers;
the functional and performance features of the internal combustion engines for traction.
Full programme
Classification of the power plant. Fundamental equations: continuity equation; energy conservation equation; momentum equation. Euler equation for turbomachinery. Flow forces. St. Venant equation. Hugoniot equation. Flow rate equation for compressible fluid. Chocked flow. De Laval nozzle. Orifice equation. Bulk modulus. Classification of pumps and compressors. Reciprocating compressors, clearance volume, staging, intercooling. Rotary (displacement) compressors, internal and backflow compression. Reciprocating and rotary pumps: pressure ripples and dampers. Dimensional analysis, similitude. Centrifugal pumps, theoretical and actual characteristics, radial thrust, multistage pumps, cavitation, priming; series and parallel. Radial flow compressors: velocity diagrams; thermodynamic of the compressor stage; stage loss; operating field. Axial flow compressors: velocity diagrams; reaction ratio; thermodynamic of the compressor stage; stage loss; stall; surge; operating field; choking; rotating stall. Free leaks pumps. Ejector. Boiler and Steam generator: classification and types; efficiency; combustion temperature; water circulation; draught. Hydro-power plants. Types of hydraulic turbines:conventional (dammed water); run of river plant; pump storage plant. Combustion process: high temperature dissociation; flame structure. Internal combustion engines for automotive applications: p-V diagram; volumetric efficiency; mean effective pressure; combustion process in compression ignition engine; combustion process in spark ignition engine; injection system for diesel and gasoline engines; energy balance; mechanical charging and turbocharging; radial turbine for turbocharging applications. Engine map and automotive applications. Pollutant emissions and aftertreatment systems.
Bibliography
All the material presented during the lectures and exercises is made available to students on the Elly platform.
Students are invited to consult the following textbooks:
Dossena, Ferrari, Gaetani, et al. - Macchine a Fluido - Città Studi Edizioni
Ferrari-Motori a combustione interna - Il Capitello
To learn more:
Caputo C. - Gli impianti convertitori di energia - Masson, Milano
Caputo C. - Le macchine volumetriche - Masson, Milano
Caputo C. - Le turbomacchine - Masson, Milano
Acton O. & Caputo C. - Collana di Macchine a fluido, 4 voll.- UTET, Torino
Lozza G. - Turbine a gas e cicli combinati - Progetto Leonardo, Bologna
Heywood - Internal combustion engines - McGraw Hill
Teaching methods
The course has 9 CFU which correspond to 72 hours of lectures. The teaching activities will be conducted through lectures.
During the lectures the course topics are dealt with from the theoretical-design point of view in order to deepen understanding of the themes by the students.
An educational visit is planned at a fluid machine manufacturer.
The exercises are designed to present some examples of machine sizing.
The slides used to support the lessons will be uploaded on the Elly platform.
To download the slides the students have to enroll in the online course.
Slides are considered an integral part of teaching material.
Assessment methods and criteria
There is only the final exam, which ensures the acquisition of knowledge and skills, the final exam includes two written tests and an oral test, without the help of notes or books.
1)first written test about the theoretical topics of the subject (average time assigned to complete the test: 50 minutes); the student is expected to answer one or more questions on different topics. The student should report all the information he is aware of by writing text, formulas, and drawing diagrams or drawings.
2) second written test relevant to one of the classroom exercises (average time assigned to complete the test: 70 minutes); the student is required to perform the exercise correctly both as a procedure and as a calculations.
After correcting the written tests the students are convoked again, usually the next day, for the communication of the results and the oral admission, oral test begin the same day.
3)Oral test (indicative time 20-30 minutes):
The oral test addresses some of the topics discussed in the course.
Students are admitted to the oral examination by completing a total score in the two written tests greater than or equal to 34. They are not admitted with one of the two votes below 16/30. Therefore, the minimum condition for accessing the oral test is 16/30 in a written test and 18/30 in the other.
The final mark is a weighted average of the votes achieved in the three tests. The oral test has the largest weight (0.4), while the written test related to exercise has the lowest weight (0.25). Honors is given in case of achieving the highest score on each item, the mastery of vocabulary is required.
The first two written tests are held the same day. Only one inscription on Esse3 is required.
The oral exam is normally held the day after the written tests day. Exceptionally the same day or two days later.
It is important to enroll (with esse3 platform) on both written and oral tests. The oral test, being the last one, appears as an appeal, the written tests appear a partial test.
Other information
Lecture attendances is highly recommended.
