COMPARISON BETWEEN H AND HERR3 MINORITY ICRF HEATING EXPERIMENTS IN JET
1. Bulk ion heating is roughly the same for H**+ and 3-He minority with AT-D = 1 keV at a normalized RF power R-RF/<n-e> = 1 x 10**-13 W m**3. At higher power levels, 3-He seems to be a little better than H**+ minority from the point of view of ion heating. However, the poor ion heating at higher power levels in H**+ case is well compensated by a better electron heating. These observations are consistent with the Stix theory in which the strong tail formed in the case of H-minority, relaxes on electrons whereas He**3-minority tail relaxes on bulk ions at the RF power densities achieved presently in JET. For example for JET parameters, at a minority power density of 0.4 W/cm**3, the fraction of power going to electrons is 0.85 and 0.2 in the case of H**+ and H**3 minority respectively. However, when RF heating power will be increased to tens of megawatts resulting in much higher minority power densities, both hydrogen and helium-3 minority are expected to transfer their energy primarily to electrons. 2. The asymptotic energy confinement times with ICRF in JET is marginally better in the case of H**+ than in the case of 3-He minority. 3. Both the (Bolometric) radiated power and the metallic impurities are worse in the case of H**+ than in the case for 3-He minority.
Bibliographic Reference: 13TH EUROPEAN CONFERENCE ON CONTROLLED FUSION AND PLASMA HEATING, SCHLIERSEE (GERMANY), APRIL 14-18, 1986 PP. 89-92 WRITE TO THE PUBLICATIONS OFFICER, JET JOINT UNDERTAKING, ABINGDON, OXON, OX14 3EA (UK) MENTIONING REPORT JET-P(86)15, 1986
Record Number: 1989125007500 / Last updated on: 1987-01-01
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