Investigation of the Characteristics of MHD Power Generation by a Corona Jet Across a Magnetic Field

In a common magnetohydrodynamic (MHD) power generation, the plasma is produced by equilibrium thermal ionization with working temperatures over 2000 K, and it is difficult to select wall materials that will withstand these high temperatures. The authors present the case that using the low-temperature corona jet produced by nonequilibrium gas discharge can lower the temperature in the MHD electrical power generation. In order to investigate the characteristics of the MHD power generation by a corona jet across a transverse magnetic field, experiments were performed to indicate the influence of airflow velocity and magnetic flux density over a multidimensional parameter space. This paper indicates that when a corona jet passes through a transverse magnetic field, it would be influenced as a result of the electromagnetic-induction phenomenon, and the induced current could be measured on the electrodes which are in the direction perpendicular to the magnetic field and the corona jet. The current increases dramatically with the increasing velocity of the airflow while not so considerably with the increasing of magnetic flux density. The amount of current induced is also influenced by the distance between the two electrodes and the distance from the electrodes to the spout of jet. The density of electric current in this experiment is lower than that generated in common MHD power-generating devices. This is primarily owing to the nonuniformity of electron density of the corona jet used in the experiments, which increases the internal resistance and limits the output of current.