To predict efficiently the heat transfer characteristics of the hydrocarbon fuel flowing inside the engine cooling channel with endothermic pyrolysis, a fast algorithm based on an n-decane thermal cracking mechanism is established for simulating the endothermic pyrolysis and supercritical-pressure heat transfer phenomena of n-decane. The three-dimensional look-up table method is adopted to acquire the thermo-physical properties of cracked mixtures. Meanwhile, the species transport equations are simplified, and finally only one species transport equation needs to be solved. The computational efficiency and accuracy of the fast algorithm are examined by comparing with the available experimental and numerical results. Results indicate that the computation efficiency is improved by about 20 times, with the computation accuracy being equivalent to that of the original algorithm, which solves fully species transport equations. Simulation of the endothermic pyrolysis and heat transfer processes of n-decane flowing inside a three-dimensional rectangular cooling channel under supercritical pressures demonstrates the accuracy of the proposed algorithm and its applicability in practice.
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