Presenting a new method to improve heat transfer in thermal cracking reactors of hydrocarbons

Subject Areas : Journal of New Applied and Computational Findings in Mechanical Systems

ali mansouri mogharab ¹ , Mehdi Ardjmand ² , jafar towfighi ³ , farhad khorasheh ⁴

1 - DEPARTMENT OF chemical engineering faculty of technical and engineering SOUTH TEHRAN BRANCH ISLAMIC AZAD UNIVERSITY Tehran Iran
2 - DEPARTMENT OF chemical engineering SOUTH TEHRAN BRANCH ISLAMIC AZAD UNIVERSITY Tehran Iran
3 - department of process engineering faculty of chemical engineering tarbiat modares university tehran iran
4 - Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran

Received: 2021-11-24 Accepted : 2022-03-13 Published : 2022-02-20

Keywords: pressure drop, heat transfer, viscose sublayer, Fin, hydrocarbon thermal cracking reactor,

Abstract :

This article which deals with the application of interdisciplinary phenomena,New methods of improving heat transfer of heat exchangers in mechanical engineering have been studied It then applies these methods to chemical reactors.Because in a chemical reactor, in addition to heat transfer and pressure drop, which are two important categories in heat exchangers, a chemical reaction is also added.Therefore, the use of heat transfer improvement methods are examined with more sensitivity so that they have the least pressure drop and the highest heat transfer.In this study, the use of straight and helical longitudinal fins in thermal cracking reactors was investigated And it was found that each of these types of fins increase the pressure drop due to friction or drag force Which have a negative effect on the chemical reaction.Then, by calculating the thickness of the viscous sub lary layer for the gaseous fluid by presenting a new method in converting the flow regime along the wall from laminar to turbulent By performing CFD simulation of peripheral grooves in a pipe Then a conclusion was suggested By using small grooves in the reactor wall can be in addition to reducing the pressure drop caused by drag force,By increasing the radial component of the velocity by more than 3 times the smooth tube, the heat transfer from the pipe wall to the fluid in the boundary layer was improved.

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