The relaxed state under the condition of a strong plasma flow is represented by the double Beltrami field(1). The generalized Bernoulli condition gives a simple relation among the flow velocity and the static pressure. To explore this new relaxation state experimentally, a toroidal device with an internal coil is suitable. Since the strong plasma flow in the toroidal direction induced by ExB flow velocity is increased as the radial direction, the high-beta plasma could be confined at the core region. The internal coil device Mini-RT is equipping a levitated ring with a high temperature superconductor coil. The magnetic field strength near the floating coil is around 0.1T, and a radio-frequency wave of 2.45 GHz is applied for the plasma production. The vacuum chamber is 1 m in diameter and 1 m in height. The Mini-RT first plasmas have been produced recently with the supported coil. Several parameters have been measured by a Langmuir probe at the plasmas. In order to excite a strong plasma flow in a toroidal direction, we are planning to introduce a radial electric field. The radial electric field in the plasma is produced by several techniques. The direct insertion of the electrode inside the plasma would be possible candidate to drive the radial electric field, as demonstrated by the CCT tokamak for achieving H-mode plasmas(2). The necessary radial electric field is a few tens kV/m in the Mini-RT device. The utilization of direct orbit loss of high-energy electrons produced by ECH is another method. The high-energy electrons will escape at the outer region of the plasma column, yielding the build-up of the radial electric field. In a dipole experiment, the high-energy electrons more than 10 keV were produced in the low background pressure such as a few micro torrs(3). We are planning the low-pressure experiment in Mini-RT.

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