Nitric oxide density distributions in the effluent of an RF argon APPJ : effect of gas flow rate and substrate

International audience; The effluent of an RF argon atmospheric pressure plasma jet, the so-called kinpen, is investigated\\r with focus on the nitric-oxide (NO) distribution for laminar and turbulent flow regimes. An\\r additional dry air gas curtain is applied around the plasma effluent to prevent interaction with the\\r ambient humid air. By means of laser-induced fluorescence (LIF) the absolute spatially resolved NO\\r density is measured as well as the rotational temperature and the air concentration. While in the\\r laminar case, the transport of NO is attributed to thermal diffusion; in the turbulent case,\\r turbulent mixing is responsible for air diffusion. Additionally, measurements with a molecular beam\\r mass-spectrometer (MBMS) absolutely calibrated for NO are performed and compared with the LIF\\r measurements. Discrepancies are explained by the contribution of the ##IMG##\\r [http://ej.iop.org/images/1367-2630/16/12/123011/njp504969ieqn1.gif] \\\\\rm N\\\\\\rm O\\_\2\\\\ and\\r ##IMG## [http://ej.iop.org/images/1367-2630/16/12/123011/njp504969ieqn2.gif] \\\\\\\rm N\\_\2\\\\\rm\\r O\\\ to the MBMS NO signal. Finally, the effect of a conductive substrate in front of the plasma jet\\r on the spatial distribution of NO and air diffusion is also investigated.