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An approximation method for evaluation of the caloric equations used in combustion chemistry simulations is described. The method is applied to generate the equations of specific heat, static enthalpy, and Gibb's free energy for fuel mixtures of interest to gas turbine engine manufacturers. Liquid-phase fuel properties are also derived. The fuels include JP-8, synthetic fuel, and two fuel blends consisting of a mixture of JP-8 and synthetic fuel. The complete set of fuel property equations for both phases are implemented into a computational fluid dynamics (CFD) flow solver database, and multi-phase, reacting flow simulations of a well-tested liquid-fueled combustor are performed. The simulations are a first step in understanding combustion system performance and operational issues when using alternate fuels, at practical engine operating conditions.

Current activities in seals for space propulsion turbomachinery that the NASA Lewis Research Center sponsors are surveyed. The overall objective is to provide the designer and the researcher with the concepts and the data to control seal dynamics and leakage. Included in the program are low-leakage seals, such as the brush seal, the “ceramic rope” seal, low-leakage seals for liquid oxygen turbopumps, face seals for two-phase flow, and swirl brakes for stability. Two major efforts are summarized: a study of seal dynamics in rotating machinery and an effort in seals code development.