Investigation of a Magnetic Heat Flux Probe in Argon Plasma Flow

An experimental investigation was carried out in order to evaluate the possible use of a newly adapted calorimetric heat flux probe in combination with a set of 8 strong permanent ring magnets to influence a high enthalpy argon plasma flow. The plasma wind tunnel facility 1 (PWK1) of Institut für Raumfahrtsysteme (IRS) was used together with the high enthalpy magneto-plasmadynamic plasma source RD5. The probe was first qualified at well known plasma conditions. Thereafter, it was equipped with permanent magnets and tested at a newly defined argon plasma condition in order to evaluate a possible influence of the magnetic field on the stagnation point heat flux. For each case, with and without magnet, two radial profiles have been recorded as well as several measurements at the center position inside the plasma flow. A definite influence on the stagnation point heat flux has been found, though the results show an increase of 17.78 % at the center position (18.15 % mean value) instead of a decrease. A possible explanation for this result is, that it might originate from the magnetic field configuration of the permanent magnets. Nomenclature m ̇ Mass flow rate (kg s−1) q ̇ Specific heat flux (kW m−2) V ̇ Volume flow rate (m3 s−1) cp specific heat at constant pressure (kJ kg −1 K−1) cp,cw Specific heat of cooling water (4.175 kJ kg −1 K−1) L characteristic length (m) St magnetic interaction parameter or Stuart number (-) v flow velocity (ms−1) Subscripts ∞ undisturbed flow cw Cooling water t tangential magnetic field componen