TOKAMAK FOUNDATION in USSR/RUSSIA

V.P. SmirnovNuclear fusion institute, RRC Kurchatov institute

22

nd

IAEA Fusion Energy Conference, Geneva, 13 – 18. 10. 2008

Content

Start of Fusion in USSR/Russia Tokamaks in Kurchatov and Kurchatov

branch/TRINITI, major steps Ioffe Institute Present status and plans

Start of USSR Fusion programme

Leaders of USSR fusion programmeAcademician L.A. Artsimovich − till 1973Academician E.P. Velikhov − after 1973

July 1950Letter of Soviet soldier O.A. Lavrentiev to Stalin

O.A. Lavrentiev

January 1951I.E. Tamm, A.D. Sakharov’s proposal on toroidal magnetic trap is approved

I.E. TammA.D. Sakharov

Toroidal systems Z-pinch Tokamak

Leaders of Kurchatov fusion team

M.A. Leontovich B.B. Kadomtsev G.I. Budker I.N. GolovinL.A. Artsimovich

T-1 is the first tokamak in the world

R = 0.67 m, a = 0.17 m, Btor = 1.5 T, Ip = 100 kA

Smooth metal liner without gaps

Stability condition was proved

Energy losses by line emission of ions with Z > 1 is a main

channel

Radiation losses contributes 80-90% of heating power

12

>=Ra

IBq T

a

Tokamak T-1(1958)

October 2008 – 50 years anniversary of Tokamak T-1 experiment start

To the end of 1950-es, M. A. Leontovich formed the unique scientific school

of theorists worked in magnetic fusion and plasma physics

М.А.Leontovich (1903-1981)

Tokamak-related areas of theoretical researches in Kurchatov:

Tokamak plasma equilibrium; Plasma stability (MHD, drift, kinetic); Transport processes; Waves in non-uniform plasma and turbulence; Plasma irradiation and atomic processes; Plasma-wall interaction

Achievements of 1950-es & 1960-es were summarized in Reviews of Plasma Physics, ed. by M.A.Leontovich, B.B. Kadomtsev, V.D. Shafranov

•Grad-Shafranov equation(V.D. Shafranov, 1957; H. Grad, 1958)

• Shafranov’s shift(V.D. Shafranov, 1959)

• D-shaped tokamak(V.D. Shafranov & L.A. Artsimovich, 1972)

Tokamak plasma equilibrium

V.D. Shafranov (born in 1929)

• Cyclotron irradiation formula(B.A. Trubnikov, 1957);

• Braginskii’s transport equations (S.I. Braginskii, 1963);

• Neoclassical theory of transport processes(A.A. Galeev & R.Z. Sagdeev, 1968);

• Trapped particle instability (B.B. Kadomtsev & O.P. Pogutse, 1966);

• Kadomtsev-Pogutse-Strauss reduced eqs.(B.B. Kadomtsev & O.P. Pogutse, 1973; H. Strauss, 1976)

Other tokamak-related issues

T-2

(1960)

T-3

(1962)

TM-2

(1965)

TM-3

(1970)

• Energy balance study

• Anomalous energy transport

•

T

e

exceed Bohm prediction by 3÷5 times

∀

τ is growing when T

e

increase

• First attempts to find a scaling low

Optimistic prediction of tokamak future

Tokamak energy balance (1959÷1970)Metal liner (500°C preheated) → Prad ≤ 0,3 Ploss

Tokamak T-3 (1962)R = 1 m, a = 0,15 m, B = 3,8 T, I = 150 kA

T-3 and TM-3 investigations of plasma energy balance confinement time were in 10 times more Bohm’s one

Time behavior of energy time τ

E

and Bohm time τ

B

Laser diagnostics approves diamagnetic measurements

Energy confinement in tokamak overcame Bohm’s prediction

Tokamak – winner fusion facility competition

Tokamak plasma ohmic heating (T-3A)

• Electron temperature reached 1 keV on T-3A tokamak (diamagnetic measurements)

• NPA diagnostic revealed Maxwelian distribution function of ions

• Ion temperature reached 350 eV in accordance with classical expectation

• First registration of thermonuclear neutron yield – start of fusion tokamak (1971)

The largest tokamak in 1975, R=1.5 m, aL=0.36 m, Bt up to 5Т, Ip up to 0.65 МА

Bohm diffusion theory for tokamak disproved finally

Electron temperature record Te≈10 keV ECRH РEC = 4 МW (1987)

ECCD efficiency determination (1991)

T-10 Tokamak (1975)

Turbulence structure determination with 3D (toroidal, poloidal, radial) correlation reflectometry

Nano-dust revealing under ITER relevant energy load

Electron Cyclotron Current Drive in T-10 ECCD efficiency in accordance with linear theoryηCD=0.03x1020AW-1m-2- 1st harmonic (1991)ηCD=0.013x1020AW-1m-2-2nd harmonic(1994)

Non inductive operation with ECCD O-mode(1991)

Excellent localization for X-mode wec ~1/30High power density up to 25Wcm-3

Sawtooth suppression by ECCD (1994) for the first time

0 50 100 1500

50

100

150 T-10

1st harm . (O -mode) 2nd harm. (X-m ode)

Iexp

CD=0.95*I calc

CD

I CD F

rom

Exp

erim

ent (

kA)

ICD From Linear Calculations (kA)

ICRF Plasma Heating and CD

Basic practical outputs Tokamaks Ion Minority heating and ion-ion Hybrid resonance discovery, tokamak TM-1Vch at Kurchatov 1970-75, and lately on many tokamaks

Applications - ion heating on on T-10, TFTR, JET, ITER, Ti up to 14 keV, energetic protons up to 7 MeV - stellarators W7-AS (magnetic beach scenario), LHD and mirrors - HFFW CD on DIII-D, NSTX and possibly on ITER - Localised MC Current Drive for NTM suppression

L.A. Artsimovich, V.D. Shafranov. Pis’ma v JETPh 15, 1972, p. 72÷76

A.M. Stefanovskiy. Pis’ma v JETPh 31, 1980, p. 663÷668

• Elongated plasma column equilibrium

• Vertical displacement event stabilization by passive and active coils

• Plasma parameters correspond to best ones of circular tokamak

T-8 (1976) Layout R = 28 cm, a = 4.8 cm, B = 0.9 T, J = 24 kA, q = 2.2, n = 7∙1013 cm

T-8 open way to D shape tokamak (T-9, 1977…)

World First Tokamak with D-shape cross-section

It is a first tokamak with superconductivity solids

Tokamak T-7

R = 1.22 m

a = 0.35 m

I = 220 kA

Btor = 3.0 T

Superconducting tokamak T-15 (1988-1995)

Parameter Design Achieved

Toroidal magnetic field, T 3.5 3.6

Plasma current, MA 1.4 1

Pulse duration, s 5 1.5

NBI, MW 6 0.6

ECRH, MW 5 1.5

First successful demonstration of a large-scale Nb3Sn magnet systems possibilities

T-15 parameters(R = 2.43 m, a = 0.78 m)

Superconducting toroidal magnet (V ≈ 50m3, W = 416 MJ)

Before compression on minor radius

After compression on minor radius

After compression on major radius

R, m 1.06 1.06 0.415

a, m 0.32 0.2 0.128

BT, Т 2.0 5.0 12.8

<n>, m-3 5х1019 1.3 х 1020 8 х 1020

I, MA 0.48 0.48 1.23

∆t, ms 30 128 10

The main design parameters of TSP tokamak

TSP tokamak (tokamak with strong magnetic field and adiabatic plasma compression) was created for achieving “breakeven” conditions in D-T plasma

TSP (T-14) tokamak TRINITI

Basic results of Ioffe institute tokamaks1970 1975 1980 1985 1990 1995 2000 2005 2010

GLOBUS-M

TUMAN-3M

FT-2

Physics of adiabatic heating

Observation of LH ion heating due to the parametric decay instability observed by enhanced scattering diagnostics

High density mode. Hot ion mode. H-mode. Central plasma fuelling by plasma gun

Effective ion and electron heating by LH waves and ITB

Ohmic H mode

Start

Start

Start

First observation of small scale ETG turbulence

Fast ion confinement in NBI regimes

Role of electric field in enhanced confinement

Neutral Particle Analysis

T-3 experiments (passive)

T-10 experiments (active)

JET experiments (MeV range)

TFTR D-T alpha experiments

JET isotope ratio experiments

ITER NPA design

FT-2 tokamak: studies of lower hybrid heating and current drive,small scale turbulence and anomalous electron transport

FT-2 parametersFT-2 parameters (R = 0.55m, aL = 0.079m, Ipl = 22kA and Bt = 2.2T, q = 6)

(РНГ ≈ 2РОН.=180 kW, ∆tLH = 5ms, f = 920MHz, N

ІІ

 ~3)

Effective LH heating of electrons and ions accompanied by transition to improved confinement regime and ITB formation Ti (100eV → 200eV); Te (300eV → 500eV);

<ne> (3.5 1019m-3 → 4.5 1013cm-3);LHCD in geometry similar to T-15M (R/r≥6) 30 32 34 36 38 40

0

100

200

300

400

500

0.0

1.4

2.9

4.3

5.7

7.1

Te, eV

ms

Te(y=1cm) Ne(y=1cm)

RF

Ne, 1013cm-3

Tion(r=0cm)

Hβ

Evolution of central plasma parameters at LHH

The first observation of small-scale ETG mode instability by UHR backscattering diagnosticsThe first observation of small-scale ETG mode instability by UHR backscattering diagnostics

2 4 6 8 10 12 140.1

1

10

100 DTEM

ETG (arb

.un.

)q r , q

θ*|n

|2

qr ρ

S

The ETG mode is observed at FT-2 at The ETG mode is observed at FT-2 at wave number wave number qrqrρρss  = 8 close to the = 8 close to the position of the ETG mode growth position of the ETG mode growth rate maximum in accordance to GS2 rate maximum in accordance to GS2 codecode

Spherical tokamak Globus-M

Engineering parameters:R=0.36 m, a=0.24 m, A=1.5

Btor=0.55 T, Ipl =0.3 MA, PAxH = 2 MW

Record plasma parameters:

<n> =1.2×10

20

m

-3

, β

N

= 6

β

T

= 15%, β

p

= 0.7

Plasma jet injection into target tokamak plasma was proposed at Globus-M as a method for central discharge fuelling

Thomson measurements of ne(R) evolution demonstrate fast two times central density increase in

50 μs after the jet injection

T-15 is expected to be main tokamak in Russia till 2040 year

2009 2011 2013 2015 2017 2019 2021

ISSUE OF T-15U FINAL PROJECT, PURCHASE OF STANDART EQUIPMENT, DEVELOPMENT OF NON-STANDART EQUIPMENT

ASSEMBLY AND ADJUSTMENT OF EQUIPMENT

PLASMA EXPERIMENTS WITH CIRCULAR PLASMA AT ADDITIONAL POWER HEATING 16 МW AND PULSE DURATION 5 S

ASSEMBLY OF DIVERTOR COILS AND IN-VESSEL ELEMENTS. PLASMA EXPERIMENTS WITH ELONGATED PLASMA AT ADDITIONAL POWER HEATING 20 МW AND PULSE DURATION 30 S

Main tasks of Т-15U

- creating the elongated separatrix magnetic configuration in existing discharge chamber;

- creating of control system for elongated configuration equlibrium;

- development, manufacturing and assembling of divertor system in discharge chamber;

- up-grading of systems for additional plasma heating and current drive, an increasing of power heating up to 22 MW and pulse duration up to 30 s;

- development and manufacture of control system for stability, equilibrium, heating and confinement of high temperature plasma in on-line regime.

Conclusion Invention of tokamak and development of its

physics and technology have provided solid starting base for way to fusion power plant (FPP)

Strategy of Russian activity in fusion is aimed to construction of FPP about 2050

Responding to signals from Russian fission power community, the activity in analysis of fusion-fission systems is revived. Fuel production and transmutation have first priory. Success of hybrids shall allow to introduce fusion in commercial use in more short time