Energy transport enhancements in a transitional thermal plasma plume

The evolution of heat and mass transfer in the initial region of a transitional plasma plume is investigated and discussed. The results show that these transport processes are controlled and limited by the plume shear layer instability. This process of laminar-turbulent transition is consecutively controlled by the plume core shear layer instability, by the "jet mode" induced by unstable shear layer, and by resonance in the jet and arc chamber. These three processes are manifested in three events. Between the first and second phase, there is a maximum of average enthalpy. The other two thresholds occur at maximum and minimum stagnation heat flux from the plume core. It seems that these processes also influence the thermal energy production in the arc chamber cavity.