The CFD study of fluid flow in the CSTR with respect to the use of different types of impellers like PBTD,PBTU,RUSHTON etc..... With the help of ANSYS Fluent

1. PICE 2017
Hosted at Department of Chemical Engineering
AISSMS COE, Pune-1
26 March 2017
Justin K George ,Dr. Vivek Vitankar, Dr. Kanhaiya R Jethani
Department of Chemical Engineering
AISSMS COE, Pune-1

2. Contents
 Introduction
 Objective
 PBTD Impeller Without Baffle
 PBTD impeller With Baffle
 Comparative Study of PBTD With & Without Baffle
 PBTU Impeller
 Rushton Turbine
 Conclusions
 References

3.  Fluid flows are governed by partial differential equations
 CFD is the art of replacing PDE systems by a set of algebraic
equations
 CFD provides a qualitative (and quantitative) prediction of fluid
flows by
• mathematical modeling (partial differential equations)
• numerical methods ( discretization and solution techniques)
• software tools (solvers ,pre-and post processing utilities)
Introduction

4. Objective
• Detailed study of flow in
 PBTD Impeller Vessel without baffle
 PBTD impeller with baffle
 Role of baffle in Mixing
 PBTU Impeller Vessel
 Rushton Turbine Vessel
with the help of CFD .

5. Parameters Dimensions
Tank diameter, T 0.5 m
Impeller diameter, D 0.17 m
Clearance, C 0.165 m
Height of liquid, H 0.5 m
Baffle width, Bw 0.05 m
Baffle thickness, BT 0.0045 m
Dimensions of the Vessel
Impeller Speed = 468.6 rpm

7. Geometry of PBTD Impeller Vessel(without baffle)

8. Velocity Contour of PBTD Without Baffle

10. Velocity Vector of PBTD Without Baffle

12. Velocity Streamline of PBTD Without Baffle

16. Geometry of PBTD Impeller Vessel (with baffle)

17. Velocity Contour of PBTD With Baffle

19. Velocity Vector of PBTD With Baffle

21. Velocity Streamlines of PBTD With Baffle

25. Geometry of PBTD With & Without Baffle

26. Velocity Vector Comparison

27. Streamline Comparison

29. WITHOUT BAFFLE WITH BAFFLE
Tangential Velocity Comparison

31. Geometry of PBTU Impeller Vessel

32. Velocity Contour of PBTU Impeller

34. Velocity Vector of PBTU Impeller

36. Velocity Streamline of PBTU Impeller

40. Geometry of Rushton Turbine Vessel

41. Velocity Contour of Rushton Turbine

43. Velocity Vector of Rushton Turbine

45. Velocity Streamline of Rushton Turbine

48. Conclusion
 CFD helps to study the fluid flow inside the system.
 MFR model is implemented to simulate the agitated impeller
involving rotating blades in CSTR
 Baffles helps to convert the tangential velocity into radial &
axial velocity components.
 The flow changes by changing the impeller in the same vessel
& with same speed.

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