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By measuring the axial profiles of thermal wall loading and radiation output in a dc vortex‐stabilized arc, it has been shown that the vortex significantly influences the energy transport in the arc. The arc was operated at 225 A in an argon vortex at a pressure of 5.5 atm. The measurements show that there is a rapid onset of thermal wall loading immediately adjacent to the upstream electrode. Furthermore, there is a significant amount of thermal wall loading upstream of the arc column, which is found to scale with the flowrate through the vortex. This fact, taken together with observations of the tracks produced by tungsten droplets on the arc wall, and photographs of the electrode regions indicate that reverse axial flow exists in the core of the arc vortex. Near the electrodes there is a region of locally increased thermal wall loading and radiation output, but between these regions there exists a region where the wall loading and radiation are axially invariant. In this region the measured wall loading is as much as 100% larger than that predicted using laminar heat transport. The scaling of this wall loading with gas flowrate in the vortex has been measured, and it has been shown that if the data are extrapolated to the no‐flow condition, the wall loading is in much better agreement with the laminar heat transport model. The existence of turbulence or Taylor–Görtler vorticies in the stabilizing gas flow are proposed as mechanisms for the enhanced thermal wall loading.