Thermohydraulic Design of Nuclear Devices 4
Code  Completion  Credits  Range  Language 

17THNJ4  Z,ZK  4  3+0  Czech 
 Garant předmětu:
 Lecturer:
 Tutor:
 Supervisor:
 Department of Nuclear Reactors
 Synopsis:

This course is set to improve the basic knowledge of students about problems of thermohydraulics. The students will learn more about flow of compressible fluids (gases, steam, ..), twophase flow (important for emergency analyses of nuclear devices, description of power loaded parts of PWR or design of BWR), about subchannel analysis of fuel assemblies and about specific modes of heat transfer (liquid metals, molten salts and gases), which can bee used for designs of GEN IV reactors. It also includes extended commentary of turbulent flow and models, which were develop for its description.
 Requirements:

THNJ1, THNJ2, THNJ3 or equivalent
 Syllabus of lectures:

1. Compressible fluids flow
Time range: 2 lectures
Speed of sound, use of 1st thermodynamic law for open thermodynamic system, conversion of enthalpy to kinetic energy, flow through gap, sound velocity, Laval nozzle (principle and calculation), steadystate shock, steam flow (real gas).
2. Twophase flow
Time range: 7 lectures
Fundamentals of twophase flow and its miscellaneous patterns, diagrams of flow, principles of twophase flow description, definition of basic quantities and their calculation (void fraction, etc. ), twophase pressure drops, basic twophase flow modeling: single fluid models, two fluid model, four equation models, nonequilibrium models, sonic velocity and critical flow; flow instability: types of instability and their nature (flow pattern instability, Ledineggs instability, dynamic instability, thermal oscillation, etc.), analysis of selected instabilities; liquidvapor separation, ..
3. Turbulent flow
Time range: 2 lectures
Description of turbulent flow, review of turbulent flow models and their principles, detailed descriptions and principles of turbulence models: Kepsilon, Komega, RNG, model with Reynolds stress, LES models, comparison of models and their use.
4. Primary circuit thermohydraulic
Time range: 1 lecture:
Hydraulic characteristic of primary circuits particular components: reactor, primary pipes, modes of main circulating pump, steam generator. Principles of CFD, short list of CFD codes and their description, problematic of interpretation of results. Principle of subchannel analysis and their use for fuel assemblies calculations, s transcription of basic flow equations for subchannel analysis, follow up equations fior subchannel analysis (turbulent mixing, pressure losses, etc.), application of subchannel analysis in computer codes and their list and features, integral and systems codes.
5. Specific modes of conduction
Time range: 1 lecture
Convection in liquid metals: thermophysical properties of the most used liquid metals (sodium, solution of PbBi), differences of properties from normal coolants and their influence on calculations, forced and natural convection at internal flow in pipes or triangular channel in lattice of fast reactors and on plane wall. Convection in gases: thermophysical properties of the helium (coolant in VHTR), differences of properties from normal coolants and their influence on calculations, influence of high velocities, forced and natural convection at internal flow in pipes and on plane wall, principles of thermohydraulics design of layer with spherical fuel elements. Convection in molten salts: thermophysical properties of fluoride molten salts, their differences from normal coolants and dependence on solutions compositions, forced and natural convection at internal flow in pipes and on plane wall.
 Syllabus of tutorials:

Lectures are in selected chapters completed with calculations of practical examples: conduction in liquid metals, two phase flow, pressure drops in primary circuits, CFD calculation.
 Study Objective:

Knowledge: detailed knowledge of selected parts of fluid mechanics, thermodynamics and heat transfer (see list of lectures) which can be used in thermohydraulic designs generally or in specific design of primary circuit and others devices in nuclear power plants.
Abilities: orientation in given issue, use gained knowledge in other courses which are engaged in thermomechanics and designs of devices in nuclear power plants. On base of given knowledge students will be able to understand and analyse behavior and control of nuclear power plant as a complex.
 Study materials:

1. Tong, L.S., Weisman, J.: Thermal Analysis of Pressurized Water Reactors, American Nuclear Society, Illinois USA, 1996, ISBN: 0894480383
2. Weseeling, P.: Principles of Computational Fluid Dynamics, Springer, 2000
3. Wilcox, D. C.: Turbulence modeling for CFD, DCW Industries, California, 2002
4. Tang Y.S., Coffield R.D., Markley R.A.: Thermal Analysis of Liquid Metal Fast Breeder Reactors, American Nuclear Society, Madison USA, 1978, ISBN: 0894480111
5. 2. Mareš R.  Šifner O.  Kadrnožka J.: Tabulky vlastností vody a vodní páry podle průmyslové formulace IAPWSIF97, VUTIUM , 1999, ISBN 8021413166
6. Lahey R.T., Moody F.J.: The ThermalHydraulics of a Boiling Water Nuclear Reactors, Američan Nuclear Society, La Grange Park, 1993, ISBN 0894480375
 Note:
 Further information:
 No timetable has been prepared for this course
 The course is a part of the following study plans: