文献类型：期刊文献

英文题名：Numerical Investigation of Reactive Cracking Flow in a Cracking Coil with 180° U-Bend Coil

作者：Li, Weijun[2,3]; Bai, Dehong[2]; Zhou, Minmin[2]; Zong, Yuan[2]; Xu, Zhimei[2]; Du, Wenli[3]; Zhao, Ling[1]

机构：[1] Xinjiang University, China; [2] School of Chemical Engineering, East China University of Science and Technology, Shanghai, 200237, China; [3] Engineering Research Center of Process System Engineering, East China University of Science and Technology, Ministry of Education, China

年份：2023

外文期刊名：SSRN

收录：EI(收录号：20230091699)

语种：英文

外文关键词：Flow patterns - Heat transfer - Vortex flow

摘要：To recognize the 180° U-bend inside the cracking coil and investigate its effect on the reactive cracking flow, flow pattern, heat transfer performance as well as the cracking results of the cracking coils with different curvature 180°U-bends have been investigated numerically. Model validation and uncertainty verification have been performed to ensure the reliability and accuracy of the numerical model and the simulation results. The results show that the artificial vortex flow induced by the 180° U-bend in a cracking coil facilitates the radial displacement of the fluid in the cross-section.And the upstream and downstream disturbance distances by the artificial vortex flow are found far beyond the physical length of the 180° U-bend, depending on the curvatures of the cracking coils. Meanwhile, heat transfer in the coils with 180° U-bend has been effectively enhanced with a thermal enhancement factor (TEF) up to 1.17 when the bend curvature is 0.3. As a result, the propane conversion and the olefin yields have been improved. Further, the field synergy principle has been adopted to illustrate the intensification mechanisms of the cracking coil with 180° U-bend. The integral Nu and the cracking results confirm that length as well as the curvature of the 180°U-bend are crucial for the intensification of the cracking reactive flow. ? 2023, The Authors. All rights reserved.