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The convective and radiative heat transfer rates are calculated for the stagnation region of the Pioneer-Venus Probe vehicles during their entry flights into the planet Venus. The nonequilibrium thermochemical state of the flow is calculated using a viscous shock-layer method accounting for oxidation of the heat shield surface by atomic oxygen and for pyrolysis-gas injection. Radiative transport along the stagnation streamline is calculated using a line-by-line technique and tangent-slab approximation. For both radiative and convective heating rates, the present results are substantially smaller than the earlier values obtained assuming equilibrium. Nomenclature C = (pn)/(pjj) s D t = mass diffusion coefficient for species /, N-m-s/kg / = dimensionless velocity function, Eqs. (3) and (4) f w = normalized ablation rate, Eq. (21) f wp = normalized pyrolysis-gas injection rate, Eq. (19) g = normalized enthalpy g r = normalized energy gain by radiation J = number flux, mol/(m 2 -s) k = Boltzmann constant k w i = surface-oxidation velocity, m/s k w2 = surface-ionic recombination velocity for C + , m/s k w3 = surface-ionic recombination velocity for O + , m/s k w4 = sublimation velocity, m/s Mi = mass of species /, kg m = ablation rate, kg/(m 2 -s) m p = pyrolysis-gas injection rate, kg/(m 2 -s) Pr = Prandtl number p = pressure, Pa q c = convective heat transfer rate, W/m 2 q r = radiative heat transfer rate, W/m 2 q* = effective radiative heat transfer rate (q r + increment in q c because of radiation absorption), W/m 2 R = nose radius, m SCj = Schmidt number for species i T = temperature, K t = time, s u -velocity in x direction, m/s V f = freestream velocity, m/s v = velocity in y direction, m/s Wf = rate of production of species /, mol/(kg-s) x = distance along wall, m y = distance from wall, m /?! = surface-oxidation probability /3 2 = surface-ionic recombination probability for C + j8 3 = surface-ionic recombination probability for O + j8 4 = evaporation coefficient for C 3 ji = concentration of species i, mol/kg e = ionization fraction 77 = dimensionless distance in y direction, Eq. (2b) K = thermal conductivity, W/(m-K) JJL = viscosity, N-s/m 2 f = dimensionless distance in x direction, Eq. (2a) p = density, kg/m 3 Subscripts E = equilibrium / = freestream p = pyrolysis-gas s = immediately behind shock wave w = wall

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The flowfield around transonic wing-body configuration was simulated using in-house CFD code and compared with the experimental data to understand the influence of several For the turbulence model, the k-ω model, the Spalart-Allmaras model, and the k-ω SST model were applied. For the spatial discretization method, the central differencing scheme with Jameson's artificial viscosity and Roe's upwind differencing scheme were applied. The results calculated were generally in good agreement with experimental data. However, it was shown that the pressure distribution and shock-wave position were slightly affected by the turbulence models and the spatial discretization methods. It was known that the turbulent viscous effect should be considered in order to predict the accurate shock wave position. 초 록 본 연구에서는 전산유체역학의 특징에 대한 이해를 위해 천음속 날개-동체 주위의 유동장을