Application of Axial Velocity Profile in Order to Develop Residence Time Distribution (RTD) for Different Laminar and Turbulent Flows

Document Type : Research Article


1 Chemical Engineering Department, Faculty of Engineering, Ardakan University, Ardakan, I.R. IRAN

2 Danesh Bonyan Parto Electronic Pishgam Kavir Cooperative Company, Yazd Science and Technology Park, Yazd, I.R. IRAN


The famous definition of RTD is based on the volumetric flow rate but is experimentally defined using the tracer concentration. These different views have erroneously limited the application of the velocity profile for RTD evaluation to the laminar flows.  In this work, a more general sense of RTD is introduced and it has been emphasized that regardless of the dispersion behavior, the velocity profile is sufficient in order to obtain the corresponding RTD. A general algorithm for RTD evaluation using axial velocity profile is developed and the relations were derived for different systems. In addition, the corresponding velocity profiles to the famous RTD models were numerically evaluated. It has been shown that the final forms are consistent compared to the previous relations for laminar flows.


Main Subjects

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