A novel ray method for the coking of n-decane in circular tubes with flexible cross-section area

Abstract

Coking of endothermic hydrocarbon fuels significantly deteriorates the efficiency of regenerative cooling for hypersonic airbreathing vehicles. A novel ray method based on dynamic mesh techniques is proposed to describe the coking behavior in a circular tube with a flexible cross-section area. This method can be used to identify metal and deposit coke efficiently, which promotes the applicability of the dynamic mesh method in flexible structures. The cooling performance of n-decane before and after coking is numerically simulated and compared. The deposition brings higher thermal risks by elevating the solid temperature. However, the deposition reduces the channel’s cross-sectional area and increases the flow speed, leading to decreased flow residence time. Because the suppressing effect from lower flow residence time outweighs the promotion effect from increased temperature, the n-decane conversion decreased after coking.