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Indexed by:期刊论文

Date of Publication:2018-04-01

Journal:JOURNAL OF THERMOPHYSICS AND HEAT TRANSFER

Included Journals:SCIE

Volume:32

Issue:2

Page Number:326-336

ISSN No.:0887-8722

Abstract:A numerical method is provided to simulate the conjugate heat transfer between coolant flow and solid material in the regenerative cooling structure of scramjet engines. The partitioned approach along with the Robin-Dirichlet interface boundary condition are chosen based on the Biot number. An in-house code is developed within the framework of OpenFOAM. Validation is carried out by comparing the numerical results with benchmark solutions for the conjugate heat transfer of backward-facing step flow and experimental data from tests on convective heat transfer of RP-3 flowing in an electrically heated tube under supercritical pressure. The coupling method shows good accuracy in the simulation of the tested cases. Coupled thermal analysis on a single channel of the regenerative cooling structure is performed to study the effect of the channel aspect ratio and secondary flow on the thermal behavior. Local heat transfer deterioration is found when the coolant sidewall temperature exceeds the pseudocritical temperature of fuel. A larger channel aspect ratio could increase the coolant side surface area but also result in thermal stratification. The relative intensity of the two factors determines whether the cooling performance is enhanced or impaired when increasing the channel aspect ratio. The turbulence-induced secondary flow has a positive effect on heat transfer by enhancing the fluid mixing. However, the effect of secondary flow is not strong enough to prevent the thermal stratification in large-aspect-ratio channels.