CALCULATION OF RADIATIVE HEAT-TRANSFER IN SF6 ARC PLASMAS

Radiation transport in SF6 are plasmas have been treated for pressures of 0.101, 0.5, and 1.0 MPa. We have investigated the use of an approx imate method of partial characteristics. We have calculated spectral a bsorptivities for SF6 plasmas for temperatures from 300 to 35 000 K, a nd have used these absorptivities to calculate the two functions desig nated Delta I and Delta Sim. These functions are integrals over all ra diation frequencies for given line segments with a linear variation of temperature along the line, The Delta I and Delta Sim. values are fun ctions of the end temperatures and the length of the line, and are use d to evaluate radiation transfer from line segments in the plasma wher e the temperature variation for each line segment is approximated as b eing linear, The validity of this method of partial characteristics ha s been demonstrated by comparing exact calculations with the approxima te calculations to evaluate radiation intensities, radiation fluxes, a nd divergence of radiation fluxes for specified temperature profiles, The method of partial characteristics has been applied to one-and thre e-dimensional calculations of radiative heat transfer in simplified te mperature profiles, Agreement up to 10% is obtained with exact calcula tions, but with a large reduction of computation time.