Effect of Mobility Tensor on the Residence Time Distribution for Viscoelastic Fluids in the Tubular Reactor

2012 ◽  
pp. 11-14
Author(s):  
Mahyar Saleh ◽  
Mohamad Samipourgiry ◽  
Nasrollah Majidian ◽  
Amir Sahand Amir Sahand
Keyword(s):  
Residence Time ◽  
Time Distribution ◽  
Residence Time Distribution ◽  
Tubular Reactor ◽  
Viscoelastic Fluids ◽  
Mobility Tensor

scholarly journals Spatial and Temporal Validation of a CFD Model Using Residence Time Distribution Test in a Tubular Reactor

Computation ◽  
2020 ◽  
Vol 8 (4) ◽  
pp. 94
Author(s):  
José Rivas ◽  
M. Constanza Sadino-Riquelme ◽  
Ignacio Garcés ◽  
Andrea Carvajal ◽  
Andrés Donoso-Bravo
Keyword(s):  
Residence Time ◽  
Time Distribution ◽  
Residence Time Distribution ◽  
Fluid Dynamic ◽  
Tubular Reactor ◽  
Temporal Distribution ◽  
Cfd Model ◽  
Ansys Fluent ◽  
Cfd Models ◽  
Temporal Validation

Computational fluid dynamic (CFD) has been increasingly exploited for the design and optimization of (bio)chemical processes. Validation is a crucial part of any modeling application. In CFD, when validation is done, complex and expensive techniques are normally employed. The aim of this study was to test the capability of the CFD model to represent a residence time distribution (RTD) test in a temporal and spatial fashion inside a reactor. The RTD tests were carried out in a tubular reactor operated in continuous mode, with and without the presence of artificial biomass. Two hydraulic retention times of 7.2 and 13 h and superficial velocities 0.65, 0.6, 1.3, and 1.1 m h−1 were evaluated. As a tracer, an aqueous solution of methylene blue was used. The CFD model was implemented in ANSYS Fluent, and to solve the equations system, the SIMPLE scheme and second-order discretization methods were selected. The proposed CFD model that represents the reactor was able to predict the spatial and temporal distribution of the tracer injected in the reactor. The main disagreements between the simulations and the experimental results were observed, especially in the first 50 min of the RTD, caused by the different error sources, associated to the manual execution of the triplicates, as well as some channeling or tracer by-pass that cannot be predicted by the CFD model. The CFD model performed better as the time of the experiment elapsed for all the sampling ports. A validation methodology based on an RTD by sampling at different reactor positions can be employed as a simple way to validate CFD models.

Investigation on a Soft Tubular Model Reactor Based on Bionics of Small Intestine – Residence Time Distribution

2014 ◽  
Vol 10 (4) ◽  
pp. 645-655 ◽  
Author(s):  
Renpan Deng ◽  
Liqing Pang ◽  
Yufen Xu ◽  
Lin Li ◽  
Xuee Wu ◽  
...  
Keyword(s):  
Small Intestine ◽  
Residence Time ◽  
Time Distribution ◽  
Residence Time Distribution ◽  
Flow Behavior ◽  
Tubular Reactor ◽  
Tubular Reactors ◽  
Fluid Particles ◽  
Mucosal Surface Area ◽  
Structure And Functions

Abstract The human small intestine is responsible for virtually all nutrient uptake and more than 95% of the water absorption in digestion, which is attributed to the vast mucosal surface area and the peristalsis of small intestine. Under the broad conceptual framework of bio-inspired chemical process engineering, by mimicking the structure and functions of small intestine, a flexible tubular reactor with villous protrusions distributed evenly on the inner wall was designed and constructed in this study. In order to understand the flow behavior in the reactor, the residence time distribution (RTD) of fluid particles in the reactor was measured by introducing electrochemical active tracer. Also, a simple mechanism of peristalsis was introduced, and its effects on the RTD in the reactor were investigated. The experimental results showed that the tailing of RTD function curve in the small intestine model reactor was extended significantly compared to a normal tubular reactors. The residence time and mixing of fluid (particles) in the reactor can be regulated efficiently by controlling the peristaltic actions (frequency and location).

scholarly journals A novel technique for residence time distribution (RTD) measurements in solids unit operations

2021 ◽  
Vol 32 (2) ◽  
pp. 611-618
Author(s):  
Atena Dehghani Kiadehi ◽  
Mikel Leturia ◽  
Franco Otaola ◽  
Aissa Ould-Dris ◽  
Khashayar Saleh
Keyword(s):  
Residence Time ◽  
Time Distribution ◽  
Residence Time Distribution ◽  
Novel Technique ◽  
Unit Operations
Sign in / Sign up

Export Citation Format

Share Document