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Cryogenics

Objectives

1) Provide general knowledge about what is cryogenics and its importance as a "technology frontier" among many sciences and engineering as thermodynamics, solid state physics, instrumentation, metrology, vacuum technology, the technologies related to space, medicine, etc .... examples of use of cryogenics will be the topics of exercises throughout the semester.

2) Provide the student the ability to, in front of a cryogenic system, quickly realize the basic principles of its operation. Facing a "simple" problem of cryogenics (Sr Engineer, I would like to cool 1 kg of copper at 80 K, what is the most economic way?), the student should know the specific requirements of the application (technical specifications), propose appropriate solutions, choose one and explain the reasons for this choice.

3) To know how to do some simple dimensioning calculations or address a diagnosis or provide orders of magnitude involved in designing a cryostat.

General characterization

Code

10530

Credits

3.0

Responsible teacher

Gregoire Marie Jean Bonfait

Hours

Weekly - 2

Total - 28

Teaching language

Português

Prerequisites

Basic of Thermodynamics

Bibliography

Notes of the teacher

Internet

Other:

The Art of Cryogenics, G. Ventura & L. Risegari, Elsevier 2010

Cryogenic Process Engineering, Klaus D. Timmerhaus, Thomas M. Flynn (auth.)

 

Teaching method

Lectures and problem-solving sessions.

At home: Presentation of cryogenics data in the plot form and solution by simple numerical calculation of small typical cryogenics problems using worksheet and web pages

Evaluation method

2 tests (1,5 h) (60%)

One laboratory session (25%)

TIC component; 3 exercises (homework), builiding of a worksheet for presentation of  cryogenic data   (15%)

 The approval of cryogenics needs a positive note for the theoretical component

Subject matter

I- Introduction
I-1 Some example of application of Cryogenics
I-2 Main cryogenic issues

II- Cryogenic liquids
II-1 My first cryostat
II-2 Cryogenic liquids (TII-3 The case of liquids helium
II-4 Características importantes dos líquidos criogénicos

III- Heat transfer by radiation
III-1 Stefan Boltzmann’s law
III-2 Thermal screen at constant temperature
III-3 Multiple thermal screen (Multilayer insulation -MLI)

IV- Heat transfer by thermal conduction
IV-1 Introduction
IV-2 Thermal conduction mechanism
IV-3 Heat transfer by thermal conduction
IV-4 Thermal conduction in gases

V- Thermal engines for cryogenics
V-1 Introduction
V-2 Liquefiers
V-3 Cryocoolers

Lab: Heat transfer coefficient between a solid wall and liquid nitrogen, Critical flux (Leidenfrost effect)