Turbocompressors

• Motori SUS, Semester 3, position 5
• Automatic Control, Semester 3, position 5
• Thermal Energy, Semester 3, position 5

1. The achievement of academic competence in the field of compressors and thermal power plant engineering. 2. Mastery of theoretical knowledge about how to transform mechanical work into internal energy of fluid by learning of thermodynamic processes and equipment. 3. The acquisition of practical skills for design and optimization of turbocompressors. 4. Mastering the techniques of process modeling.

On completion of this programme, it is expected that student will be able to: • perform design of a multistage axial compressor writing own program code, • select dimensionless parameters of compressor stages, • apply one-dimensional theory of the compressor stage, determine the main dimensions of the stage, calculate efficiency and the stage operating parameters, • apply the appropriate solutions of 3D flow and define 3D blade geometry of the compressor stage, • select the type of airfoils, calculate the aerodynamic losses and deviation, • define the meridian flow path of the entire machine, • apply different control modes for the turbocompressor, • analyse compressor behavior at off-design operating parameters.

1. Thermodynamic background of turbocompressors. Isothermal, isentropic, polytropic and real process. Isentropic efficiency and polytropic efficiency. 2. The aerodynamic basics of turbocompressors. 3. Cascades of turbocompressors. Geometric and operating parameters of the cascades. 4. Main aerodynamic cascade parameters. Aerodynamic losses in compressor stages. 5. Theory of the cascade aerodynamic coefficients. 6. Mean-line theory of compressor stages. Energy balance, Euler equation. 7. Dimensionless parameters of turbocompressors. Dimensionless velocity triangles. Dependence of the compression ratio on the operating parameters. 8. Dependence of efficiency of the normal stages of axial compressor from the cascade aerodynamic coefficients and from the stage operating parameters. 9. 3D flow in axial compressors stages. Optimal design factors. Determination of main dimensions of axial compressors. 10. The behavior of the compressors at variable loads. Regulation of turbocompressors.

Practical training is carried out through: Auditory exercises: Introduction. Energy conversion in the compressors. The types of compressors. Application areas. Instructions for project 1: Calculation of main dimensions of axial compressors. Instructions for project 2: Design of the compressors cascades. Project development: Calculation of main dimensions of axial compressors. Calculation of compressors cascades. Labs: Learning the principles of operating and design of compressors in the Laboratory of thermal turbomachinery.

Passed exams in Thermodynamics and Fluid mechanics.

Petrovic, M.: Gas turbines and compressors, script, 2004. Petrovic, M.: Gas turbines and compressors, introduction for exercises, 2004. Petrovic, M. scripts and handouts for Gas turbines Instructions for performing laboratory exercises Software package for calculating of properties of air and combustion products

Total assigned hours: 75

New material: 20
Elaboration and examples (recapitulation): 10

Auditory exercises: 9
Laboratory exercises: 4
Calculation tasks: 0
Seminar paper: 0
Project: 17
Consultations: 0
Discussion/workshop: 0
Research study work: 0

Review and grading of calculation tasks: 0
Review and grading of lab reports: 1
Review and grading of seminar papers: 0
Review and grading of the project: 7
Test: 2
Test: 0
Final exam: 5

Activity during lectures: 5
Test/test: 10
Laboratory practice: 5
Calculation tasks: 0
Seminar paper: 0
Project: 30
Final exam: 50
Requirement for taking the exam (required number of points): 25

Petrovic, M.: Gas turbines and compressors, script, 2004.; Stojanovic, Thermal Turbomachinery, Gradjevinska knjiga, Belgrade, 1967.; Cohen, H., Rogers,G.F.C., Saravanamuttoo, H.I.H.: Gas turbine theory, Logman, 1997.; Traupel,W.: Thermische Turbomaschinen, Springer verlag, Berlin, 1982.; Boyce, M.: Gas turbine engineering hadbook, GPB, Boston 2002.