A NEW VORTEX METHOD OF PLASMA INSULATION AND EXPLANATION OF THE RANQUE EFFECT

The efficiency of thermal insulation of a microwave-generated plasma u sing reverse vortex flow was investigated experimentally and by numeri cal simulations. Comparison with the conventional Vortex method of pla sma insulation was made. Changing the location of the vortex inlet to the exit end of the plasma torch leads to a significant decrease of th e heat loss to the wall; from 30% to 5%. This result contradicts the t raditional explanation of the Ranque effect. A new simple explanation of the Ranque effect of energy separation in the vortex tube is propos ed. Energy separation takes place due to radial motion of turbulent mi cro-volumes with differing tangential velocities in the strong centrif ugal field. The new model of energy separation explains such apparentl y mysterious phenomena as the counter-rotation of the central vortex f low layers observed in some experiments and in numerical simulations. A new approach for consideration of the confined vortex flows is descr ibed.