Abstract
Experiments using time-resolved emission spectroscopy are carried out to determine the temperature in a direct current (DC) electric discharge generated in a high-speed flow. The experiments are conducted in the STA shock tunnel at the French-German Research Institute of Saint-Louis (ISL) at a Mach number of 4.6 and at flow conditions corresponding to an altitude of 8 km. Nitrogen is used as test gas. The electric arc is generated on the surface of a wedge with a sharp leading edge. The electrodes of the DC plasma actuator are installed flush with the surface. During the discharge, the input power is regulated to a constant value of 10 kW. The B2Σ+ − X2Σ+ violet system of the CN molecule with the band head around λ = 388.34 nm is used for determining the vibrational and rotational temperatures in the positive column of the electric arc. In addition, copper atomic lines with the wavelength band between λ = 517 nm and λ = 525 nm are utilized to obtain the electronic-excitation temperature in the plasma. Thermal nonequilibrium is detected between the vibrational and rotational modes of the CN molecule in the outer layers of the positive column of the arc. The maximum electronic excitation temperature measured ranges during the experiment from 9,000 to 13,300 K leading to a mean value of 10,670 K.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.