Coupled DSMC—PMC Radiation Simulations of a Hypersonic Reentry
نویسندگان
چکیده
bhw = line half-width, Å E = radiative energy, W Eabs = radiative energy absorbed by cell, W Ebundle = radiative energy carried by photon bundle, W Eemis = emission energy, W Etrans = transmitted radiative energy, W Kn;1 = freestream Knudsen number, dimensionless k, k1, k2 = line-center index, dimensionless L = nose radius of the Stardust blunt body, m l1;2 = ratio between face endpoints, m Nrays per cell = number of rays emitted from one cell Ntotal rays = initial number of rays for an entire computational domain na = atom number density, m 3 ne = electron number density, m 3 n = ion number density, m 3 Qemis = total integrated emission coefficient,W=cm-sr Qemis;k = accumulated atomic emission lines from i 1 to k, W=cm-sr Qemis; = partially integrated emission coefficient, W=cm-sr qR = radiative heat flux,W=m qc = convective heat flux,W=m R = random number, dimensionless Rc = radius of curvature, m r = radial component of photon travel distance in a cell, m S = distance from stagnation point, m Sd = distance from emission point to cell-face intersection point, m sx, sy, sz = directional cosines in a Cartesian coordinate system Trot = rotational temperature, K Ttrn = translational temperature, K Tvib = vibrational temperature, K Te = electron temperature, K Vcell = cell volume, m V1 = freestream velocity, m=s X = horizontal coordinate of direct simulation Monte Carlo domain for the Stardust geometry, m xi, yi, zi = intersection points of a photon bundle with a cell face, m xe, ye = emission locations, m x1, x2 = coordinates of cell boundary along X axis, m Y = vertical coordinate of direct simulation Monte Carlo domain for the Stardust geometry, m y1, y2 = coordinates of cell boundary along Y axis, m Z = horizontal coordinate of photon Monte Carlo domain for the Stardust geometry, m = optical length, dimensionless "i = emission coefficient of a bound-bound transition at the line-center wavelength, W=cm-sr " = emission coefficient at a wavelength, W=cmm-sr = polar angle, rad = absorption coefficient, cm 1 = wavelength, Å
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