Course detail

Fluid Machinery I

FSI-MS1 Acad. year: 2026/2027 Winter semester

The course focuses on hydraulic designs and CFD calculations of flow parts of hydraulic pumps and turbines, i.e., impellers, volutes, distributors, etc. The course also provides an introduction to the behavior of machines during changes in operation, cavitation phenomena, the emergence of axial and radial forces and their elimination. It focuses on the hydraulic concept of a fluid machine for given parameters.

Language of instruction

Czech

Number of ECTS credits

6

Supervisor

Ing. David Štefan, Ph.D.

Department

Energy Institute

Entry knowledge

Students are expected to be familiar with the basic parts of hydromechanics, especially with basic principles of work of fluid machines. Another prerequisite is basic knowledge of 3D modeling in a CAD environment and basic knowledge of CFD calculations.

Rules for evaluation and completion of the course

Credit conditions: participation in the exercises and development of the assigned design and CFD calculation of the hydraulic parts of the turbo-machine.

The exam consists of a written and oral part.

Participation in the exercises is mandatory. Any absence is compensated according to the agreement with the teacher.

Aims

The aim of the course is to prepare the student to understand the hydraulic design and CFD calculations of the basic parts of a fluid machine (pumps, turbines) and their other parts (spirals, distributors), the behavior of machines during operational changes, the occurrence of cavitation, radial and axial forces, and the characteristics of a fluid machine.

The student will understand the basic principles of hydraulic design and CFD calculations of a fluid machine.

The study programmes with the given course

Programme N-SUE-P: Computational Simulations for Sustainable Energy, Master's, compulsory-optional

Programme N-ETI-P: Power and Thermo-fluid Engineering, Master's
specialization FLI: Fluid Engineering, compulsory

Type of course unit

 

Lecture

39 hours, optionally

Syllabus


  1. Specific speed. Rotating channel theory. Calculation of impeller head.

  2. Pump behavior when changing speed. Design of the main dimensions of the impeller – diameter and width. Design of the shape of the meridian and the inlet part of the impeller. Geometric corrections – impeller trimming and blade under-filing.

  3. Conformal transformation and design of the blade centerline.

  4. Design of the blade centerline. Inflection. Conformal transformation for the turbine direction.

  5. Design of the volute. Design of the outlet diffuser. Cavitation depression.

  6. Hydraulic forces acting on the impeller – radial force, axial force. Elimination of hydraulic forces. Sealing rings and gaps – volumetric losses.

  7. Multistage pumps. Mixed-flow pumps. Axial pumps.

  8. CFD calculations of hydraulic machines.

  9. Full (4-quadrant) characteristic. Pump as turbine. Turbine as pump. Introduction to hydraulic turbines (Francis turbine, Kaplan turbine, Pelton turbine).

  10. Hydraulic turbines. Basic design principles. Turbine characteristic curves.

  11. Hydrodynamic similarity. Unit values ​​of flow, speed, torque and power. Hydraulic efficiency of the model and conversion to a prototype.

  12. Cavitation in hydraulic turbines. Vortex rope in the draft tube. Draft tube and its function.

  13. Reserve – called lecture from industry.

Laboratory exercise

26 hours, compulsory

Syllabus


  1. Analysis of the specific energy of a centrifugal pump. Effect of impeller geometry and blades. Effect of the second term of the Euler pump equation (flow pre-rotation).

  2. The behavior of the pumps when the speed changes. Calculation of dissipation. Impeller Trimming and blade modifications.

  3. Design of centrifugal pump / turbine hydraulics – part 1. Calculation of the basic dimensions of the impeller.

  4. Design of centrifugal pump / turbine hydraulics – part 2. Creation of meridional section.

  5. Design of hydraulics of a centrifugal pump / turbine – part 3. Calculation of the shape of the blades and creation of 3D geometry of the impeller within the Ansys BladeGen software.

  6. Design of hydraulics of a centrifugal pump / turbine – part 4. Creation of a computational grid of the impeller within the Ansys TurboGrid software. Calculation of the shape of the spiral.

  7. Design of hydraulics of a centrifugal pump / turbine – part 5. Creation of a computational grid of spiral. Creation of the geometry and computational grid of the pump inlet.

  8. Setting up and running the CFD calculation of the designed centrifugal pump / turbine hydraulics in the Ansys CFX environment.

  9. Evaluation of CFD calculation results of a centrifugal pump / turbine. Post-processing of data within the CFD-Post software.

  10. Calculation of axial and radial forces acting on the runner. Empirical estimates and method of calculation using CFD.

  11. Basic design of axial pump/turbine blades

  12. Basic design of the Francis turbine channel shape with regard to specific speed

  13. Credit – hydraulic design check