Boundary Layer/Streamline Surface Catalytic Heating Predictions on Space Shuttle Orbiter

Abstract

This paper describes the analysis of localized catalytic heating effects to the U.S. Space Shuttle Orbiter thermal protection system. The analysis applies to the high-temperature reusable surface insulation on the lower fuselage and wing acreage, as well as the reinforced carbon-carbon on the nose cap, chin panel, and wing leading edge. The objective was to use a modified two-layer approach to predict the catalytic heating effects on the Orbiter windward thermal protection system assuming localized highly catalytic or fully catalytic surfaces. The method incorporated the boundary layer integral matrix procedure-kinetic code with streamline inputs from viscous Navier-Stokes solutions to produce heating rates for localized fully catalytic and highly catalytic surfaces as well as for nominal partially catalytic surfaces (either reinforced carbon-carbon or reaction cured glass) with temperature-dependent recombination coefficients. The highly catalytic heating results showed very good correlation with Orbiter experiments STS-2, -3, and -5 centerline and STS-5 wing flight data. Recommended catalytic heating factors were generated for use in future shuttle missions to perform quick-time atmospheric reentry analysis of damaged or repaired thermal protection system areas. The catalytic factors are presented along streamlines and as a function of stagnation enthalpy for use with arbitrary shuttle trajectories. Nomenclature b= bump factor equal to ratio of local catalytic to nominal heating rate C i = mass fraction of ith species D ij = multicomponent diffusion coefficient ê ;ê ;ê = streamline coordinate-aligned unit vectors H cl = arcjet nozzle centerline enthalpy, J=kg H w = wall enthalpy, J=kg h 0 = enthalpy of formation, J=kg h arc = heating parameter î;ĵ;k = Cartesian-aligned unit vectors L = Orbiter reference length, m M i = normal mass flux of ith species, kg=m 2 s P meas = measured test article surface pressure, N=m 2 q = heat flux per unit area, W=m 2 r = position vector, m T = temperature, K t = time, s u; v; w = Cartesian velocity components, m=s V = velocity vector, m=s Xo; Yo; Zo = axial, lateral, and vertical shuttle coordinates, m x = Orbiter axial distance from apex, m x; y; z = Orbiter Cartesian axis system, m = chemical energy accommodation coefficient = catalytic recombination rate coefficient = emissivity = thermal conductivity, W=m 2 K ; ; = streamline coordinate system = density, kg=m 3 = Stefan-Boltzmann constant (5:67 10 8 W=m 2 K 4 )

Adiabatic shock capturing in perfect gas hypersonic flows

“…Historically, this distinction has been exploited 1042 B. S. KIRK in the so-called 'two-layer' approaches that decouple and iteratively solve an inviscid flowfield and boundary-layer approximation [1]. This approach is still used to some extent today [2], but full Navier-Stokes simulations (which simultaneously model the viscous and inviscid effects in the entire domain) are now commonplace and are a key component in engineering design and analysis.…”