Laser Doppler anemometry under plasma conditions. Part II. Measurements in an inductively coupled r.f. plasma

Laser Doppler anemometry is used for the measurements of the plasma and particle velocity profiles in the coil region of an inductively coupled r.f. plasma. Results are reported for a 50 mm i.d. induction plasma torch operated at atmospheric pressure with argon as the plasma gas. The oscillator frequency is 3 MHz and the plate power is varied between 4.6 and 10.5 kW. Plasma velocity measurements are obtained using a fine carbon powder as a tracer. Measurements are also given for larger silicon particles () centrally injected into the discharge under different operating conditions.Nomenclature d_p particle diameter - P₀ plasma power - Q₁ powder carrier gas flow rate - Q₂ plasma gas flow rate - Q₃ sheath gas flow rate - r distance in the radial direction - V axial plasma velocity - V_p axial particle velocity - Z distance in the axial direction - standard deviation