A prediction technique for ablative material performance under high-shear re-entry conditions.

Chapter 14: Mathematical Modeling of Heat and Mass Transfer during Aerothermochemical Destruction of Thermal Protection Materials

“…Without diminishing the significance of the theory of ablation of thermal protection materials due to consecutive spalling of material layers, which was developed in Refs. 34 and 35, we should note the limited possibility of using this theory in practice. The point is that preference is most often given to materials possessing a sufficiently high effective enthalpy (i.e., materials for which the erosion process does not play the key role in the overall mechanism of ablation).…”

Decomposition rate of a phenolic resin.

“…where m may refer to any individual component ; 9 m is a constant of integration representing the weight left at t = oo, and a mj and AJ are constants determined by the actual reaction rates. The combined weight of all the components may be written as (2) where 2q has been written as…”

“…In particular, it has been shown that depth of charring strongly influences the response of an ablative material to aerodynamic shear effects. 2 Previous attempts to predict the decomposition rates of phenolics have usually assumed single reactions of first order. More realistic approaches have attempted to match thermogravimetric test data with a number of reactions of varying orders.…”