1 Young-Ju Lee Vacuum & Cryogenic Engineering Team National Fusion Research Institute Young-Ju Lee Vacuum & Cryogenic Engineering Team National Fusion Research Institute Applied Cryogenic Engineering for the Fusion & SC Accelerator

2 Application of Cryogenic Eng. Introduction; Cryogenic System I I III Summary IV Core Cryogenic Technology II

3 Introduction

4 Global Helium Refrigerators YearIssue 1903He gas was found in a natural gas 1908First helium liquefaction by H. K. Onnes SiteNamePlaceCapacity (4.5 K eq.)Purpose KoreaKSTAR HRSDaejeon9 kWSC tokamak KHNP TRFGyeongju2 kWTritium isolator RAON HCPDaejeon18 kWSC accelerator AbroadCERN LHCGeneve (CH)18 kW (8 sets)SC accelerator ORNL SNSOak Ridge (US)~ 6 kWSC accelerator ITER HRSAxe (France)25 kW (3 sets)SC tokamak

5 To achieve the superconducting tokamak construction and operation experiences, To develop high performance steady- state operation physics and technologies that are essential for fusion reactor development Major radius, R 0 Minor radius, a Elongation,  Triangularity,  Plasma volume Plasma surface area Plasma cross section Plasma shape Plasma current, I P Toroidal field, B 0 Pulse length  N Plasma fuel Superconductor Auxiliary heating /CD Cryogenic Parameter 1.8 m 0.5 m m 3 56 m m 2 DN, SN 2.0 MA 3.5 T 300 s 5.0 H, D Nb 3 Sn, NbTi ~ 26 MW 9 KSTAR 6.2 m 2.0 m m m 2 22 m 2 SN 15 (17) MA 5.3 T 400 s 1.8 (2.5)* H, D, T Nb 3 Sn, NbTi 73 (110) MW 75 ITER SC Tokamak; KSTAR (Korea) KSTAR mission and Parameters

6 KSTAR HRS Schematic layout of the KSTAR main cryogenic system WCS and GMS LP : 2 X MYCOM400S & Siemens5010 HP : 2 X MYCOM320S & Siemens5810 Electricity : 3.6 MW Mass flow : ~1.1 kg/s ORS : Coalescer & Charcoal adsorber Pure GHe : 12,000 Nm 3 Impure helium tank : 100 m Recovery comp. & purifier : 32 g/s Cold Box Cooling power : 9 6 expander turbines 11 Al fin-plate HXs (4 blocks) 2 X 80 K adsorber 20 K adsorber Cryogenic valves : 49 EA 7 Al LHe/SHe HXs 2 X SHe circulator Cold compressor Thermal damper: 4 m 3 LHe (4.3 K) Distribution Box#1 D/B# cryogenic valves. 6 warm valves - Dimension : 3.5 m X 6 m 5 cryogenic transfer lines (CTLs) - TL1 : 27 m, 17 internal cooling tubes - TL2 : 6.2 m, 25 internal cooling tubes - TL3 : 6.2 m 18 internal cooling tubes - TL5 : 26 m, 4 internal cooling tubes - TL6 : 16 m, 8 internal cooling tubes Helium Distribution System & KSTAR

7 Process flow diagram of the KSTAR main cryogenics System Design; Refrigerator

8 Simple P&ID of the KSTAR HDS System Design; Distribution System

9 9 SC Accelerator; RAON (Korea)

10 Core Cryogenic Technology

11 Extreme Core Technology & Cryogenic Engineering ParameterTechnologyApplication Low Temperature300~4.2 K; Cryogenic engineering Commercial; water, foods, … Industrial; LNG, LPG, …. Science; nitrogen, hydrogen, helium, … High Temperature ~ 1000 K; Material & high energy engineering Metal & alloy Energy; nuclear fission & fusion Science; accelerator Low Pressure 1E5 ~ 1E-10 Pa; Vacuum technology Industrial; semiconductor & application, foods, … Space science, energy, …. High Pressure~ 100 bar Pressure vessel Energy; heat exchanger Deep sea High Voltage~ 10 kV Glow discharge Electrical energy transport Fusion energy High Currents~ 10 kAFusion energy High Magnetic Fields ~ 10 Tesla Medical; MRI Science Fusion energy High Frequency~ GHzScience (accelerator, …)

12 Temperature

13 Pressure

14 Vacuum Pressure

15 Magnetic Fields

16 Frequency

17 Application of Cryogenic Engineeing

18 Helium Refrigerator  Pressure vessel; Helium storage tank  Helium recovery system  Warm helium compressor  Helium purifier  Oil/dust filters  Vacuum cryostat; Cold box  Heat exchanger  Cryogenic turbine & cold compressor  Instruments; cryogenic valve, flowmeter, temperature/ pressure sensor, etc….  Control/monitoring/safety engineering

19 Fusion Engineering  Superconducting cable (cable-in-conduit type)  Superconducting magnet (~ 10 Tesla, fast sweep)  Magnet quench protection system  Current feeder (300 ~ 4.5 K)  Helium distribution system  Vacuum cryostat  System design engineering  System analysis (FEA & thermo-hydraulic analysis)  Performance test facilities  Instrumentation & control system  High voltage insulation (~10 kV)

20 SC Accelerator Engineering  DC superconducting magnet (LTS & HTS, ~ 1 Tesla)  Magnet quench protection system  Current feeder (300 ~ 4.5 K)  Superconducting cavity and cryomodule  Helium distribution system  Vacuum cryostat  System design engineering  System analysis (FEA & thermo-hydraulic analysis)  Performance test facilities  Instrumentation & control system

21 The Other Application Area  LNG industry  Liquid nitrogen industry  Hydrogen gas liquefaction & storage  MRI  Space science & engineering  Etc.

22 Summary

23 Summary  Helium cryogenic engineering has more than 100 years of history.  But, there have been applied in many areas such as future fusion energy, industry, medical science, space science, pure science, and so on, for the mankind.  As time goes on, the cryogenic engineering will be much more important together with core technologies such as high/low temperature, high/low pressure, high voltage/ currents, high frequency, and so on.

24 THANK YOU FOR THE ATTENTION!!!