Turbomachines

Duration

26h Th, 26h Pr

Number of credits

Lecturer

Koen Hillewaert

Language(s) of instruction

French language

Organisation and examination

Teaching in the first semester, review in January

Schedule

Schedule online

Units courses prerequisite and corequisite

Prerequisite or corequisite units are presented within each program

Learning unit contents

Unit 1 - Generalities

• Introduction and classification of turbomachines;
• Fluid Dynamics: conservation equations; similarity; lifting surfaces;
• Turbomachines: frames of reference, Euler equation, rothalpy; velocity triangles; total conditions in the absolute and relative frame;

• Axial passages: force balances, power exchanges and losses; similarity, stage coefficients and loss parameters; radial equilibrium
• Radial passages with or without blades

• hydraulic forms of energy, head, head losses and hydraulic diagrams
• cavitation
• waterhammer

• similarity: classification, scaling rules and extrapolation
• description of radial and axial pumps
• energy balance
• estimation of the conditions throughout the machine
• operating characteristics
• cavitation and NPSH

• operating point in a circuit: head, flow rate and NPSH
• control strategy: throttling, speed regulation, bypass
• multistage pumps, trimming and suppliers catalogues

• similarity: classification, scaling rules, normalised operating maps
• description of turbine types and operation
• power balance and efficiencies
• estimation of conditions throughout the machine
• operating curves and regulation
• cavitation

• state  equations; Mollier h-s diagram; polytropes;
• Mach number and sonic effects; total conditions; shocks
• flow in ducts: Fanno, Rayleigh and de Laval
• iterative estimation of flow conditions 

• Eulers equations, rothalpy, total conditions in the absolute and relative frame, stage Mollier h-s diagram
• iterative estimation of the thermodynamic conditions in the turbomachine
• similarity scaling, corrected and reduced conditions

• construction of axial and radial compressors
• definition of efficiencies
• speed characteristics and operating limits
• flow in typical compressor passages
• stall and surge
• impact of compressibility on off-design operation and variable vanes

• construction of axial and radial turbines
• definition of efficiencies of machine, stage and passage 
• operating maps;
• typical flows in turbomachinery passages
• Steam turbines: choice of stage types through the machine; regulation.

• choice of operating parameters of the Brayton cycle in function of technology 
• component matching
• stationary gas turbines
• turboreactors: propulsive efficiency, performance parameters, introduction to the cycles and technology of civil and military engines; turboprops; recent evolutions

Learning outcomes of the learning unit

• Understand the operation, the choice and the design consideration of the machine / stages in function of the application, its duty and the operating conditions;
• Estimate the operating point of a machine in an installation;
• Reconstruct the thermodynamic and fluid dynamic conditions in key locations of the machine and based on that provide an estimate of the performance;
• Provide a rough predesign of a stage or a simple machine;

Prerequisite knowledge and skills

During the course, the bases will be recalled and reformulated in the framework of turbomachinery; nevertheless the following knowledge is prerequisite and should be revised in preparation of the course:

• applied thermodynamics: main laws, polytropes, Mollier diagrams
• fluid dynamics;
• Newtonian mechanics: forces, torque, work, frame of reference

Planned learning activities and teaching methods

• Weekly course sessions, on average 3 hours of theory and 1/2 hour of exercises
• 1 lab for measuring the performance of a turbomachine per group of 2 students
• 1 individual project on the design/performance analysis of a machine

Mode of delivery (face to face, distance learning, hybrid learning)

Face-to-face course

Recommended or required readings

Course notes and exercise compendium on e-campus;

Tables and articles e-campus.

Recommended generalizing books (available in applied sciences library,* electronic format)

• Fundamentals of Turbomachines, E. Dick 
• Turbomachinery Flow Physics and Dynamic Performance, M. Schobeiri
• The Dynamics and Thermodynamics of Compressible Fluid Flow, E. Shapiro
• Aero-Thermodynamics and flow in Turbomachines, M.H. Vavra

• Hydrodynamics of Pumps, C.E. Brennen*
• Design and analysis of radial compressors, R. Van den Braembussche*
• Axial flow turbines, fluid mechanics and thermodynamics, J.H. Horlock
• Axial flow compressors, fluid mechanics and thermodynamics, J.H. Horlock
• Compressor aerodynamics, N. Cumpsty
• Jet propulsion : a simple guide to the aerodynamic and thermodynamic design and performance of jet engines, N. Cumpsty

Exam(s) in session

Any session

- In-person

written exam ( open-ended questions ) AND oral exam

Written work / report


Additional information:

The total grade is composed of the marks on

• the report of the lab session
• the report of the design/performance assessment exercise
• the oral exam on theory
• the written exam on exercises

Work placement(s)

N/A

Organisational remarks and main changes to the course

Contacts

It is to first pose questions on theory, exercises and projects, either directly during the course sessions, or on the dedicated forum on e-campus, in order to share the information with as many as possible and to have a rather immediate answer. If still needed, personal or group appointments can be made via mail

• Koen Hillewaert (enseignant) koen.hillewaert@uliege.be
• Nicolas Leclère (assistant) n.leclere@uliege.be

Association of one or more MOOCs

There is no MOOC associated with this course.