Derksen 10<SUP>th</SUP> European Conference on Mixing

1. Auflage 2000
ISBN: 978-0-08-052579-2
Verlag: Elsevier Reference Monographs
Format: PDF
Kopierschutz: Adobe DRM (»Systemvoraussetzungen)

E-Book, Englisch, 572 Seiten

Traditionally, fluid mixing and the related multiphase contacting processes have always been regarded as an empirical technology. Many aspects of mixing, dispersing and contacting were related to power draw, but understanding of the phenomena was limited or qualitative at the most.
In particular during the last decade, however, plant operation targets have tightened and product specifications have become stricter. The public awareness as to safety and environmental hygiene has increased. The drive towards larger degrees of sustainability in the process industries has urged for lower amounts of solvents and for higher yields and higher selectivities in chemical reactors. All this has resulted in a market pull: the need for more detailed insights in flow phenomena and processes and for better verifiable design and operation methods.
Developments in miniaturisation of sensors and circuits as well as in computer technology have rendered leaps possible in computer simulation and animation and in measuring and monitoring techniques.
This volume encourages a leap forward in the field of mixing by the current, overwhelming wealth of sophisticated measuring and computational techniques. This leap may be made possible by modern instrumentation, signal and data analysis, field reconstruction algorithms, computational modelling techniques and numerical recipes.

Autoren/Hrsg.

Derksen, J.J.

Inhaltsverzeichnis

1;Cover;1
2;Contents ;4
3;Preface;10
4;Mixing: Terms, Symbols, Units;14
5;PART I: TURBULENCE CHARACTERISTICS IN STIRRED TANKS;32
5.1;Chapter 1. Trailing vortex, mean flow and turbulence modification through impeller blade design in stirred reactors;32
5.2;Chapter 2. Turbulence generation by different types of impellers;40
5.3;Chapter 3. Limits of fully turbulent flow in a stirred tank;48
6;PART II: MEASUREMENTS IN CHEMICALLY REACTING FLOWS;56
6.1;Chapter 4. Spatially resolved measurements and calculations of micro-and macromixing in stirred vessels;56
6.2;Chapter 5. Characterisation and modelling of a two impinging jet mixer for precipitation processes using laser induced fluorescence ;66
6.3;Chapter 6. Four-dimensional laser induced fluorescence measurements of micromixing in a tubular reactor;76
7;PART III: MODELLING OF MICRO-MIXING;84
7.1;Chapter 7. Simulation with validation of mixing effects in continuous and fed-batch reactors;84
7.2;Chapter 8. A computational and experimental study of mixing and chemical reaction in a stirred tank reactor equipped with a down-pumping hydrofoil impeller using a micro-mixing-based CFD model ;92
7.3;Chapter 9. Mixing with a Pfaudler type impeller: the effect of micromixing on reaction selectivity in the production of fine chemicals ;100
7.4;Chapter 10. Comparison of different modelling approaches to turbulent precipitation;108
7.5;Chapter 11. Application of parallel test reactions to study micromixing in a co-rotating twin-screw extruder;116
7.6;Chapter 12. Solid liquid mixing at high concentration with SMX static mixers;124
8;PART IV: EFFECTS OF VISCOSITY AND RHEOLOGY ON MIXING;132
8.1;Chapter 13. Influence of viscosity on turbulent mixing and product distribution of parallel chemical reactions;132
8.2;Chapter 14. Mixing of two liquids with different rheological behaviour in a lid driven cavity;140
8.3;Chapter 15. Mobilization of cohesive sludge in storage tanks using jet mixers;148
9;PART V: SLURRY SYSTEMS;156
9.1;Chapter 16. CFD simulation of particle distribution in a multiple-impeller high-aspect ratio stirred vessel;156
9.2;Chapter 17. Power consumption in slurry systems;164
10;PART VI: LIQUID-LIQUID DISPERSIONS;172
10.1;Chapter 18. Drop break-up and coalescence in intermittent turbulent flow;172
10.2;Chapter 19. Measurement and analysis of drop size in a batch rotor-stator mixer;180
10.3;Chapter 20. The impact of fine particles and their wettability on the coalescence of sunflower oil drops in water;188
10.4;Chapter 21. Influence of impeller type and agitation conditions on the drop size of immiscible liquid dispersions;196
10.5;Chapter 22. Experimental findings on the scale-up behaviour of the drop size distribution of liquid/liquid dispersions in stirred vessels;204
10.6;Chapter 23. Investigations of local drop size distributions and scale-up in stirred liquid-liquid dispersions;212
11;PART VII: GAS-LIQUID SYSTEMS;220
11.1;Chapter 24. Gas-liquid mass transfer in a vortex-ingesting, agitated draft-tube reactor;220
11.2;Chapter 25. Modelling of the interaction between gas and liquid in stirred vessels;228
11.3;Chapter 26. Experimental investigation of local bubble size distributions in stirred vessels using Phase Doppler Anemometry;236
11.4;Chapter 27. Void fraction and mixing in sparged and boiling reactors;244
12;PART VIII: PARTICLE COLLISIONS IN CRYSTALLISATION;252
12.1;Chapter 28. A numerical investigation into the influence of mixing on orthokinetic agglomeration;252
12.2;Chapter 29. An experimental method for obtaining particle impact frequencies and velocities on impeller blades;262
13;PART IX: ADVANCED CFD;270
13.1;Chapter 30. Comparison between direct numerical simulation and ke prediction of the flow in a vessel stirred by a Rushton turbine;270
13.2;Chapter 31. The use of large eddy simulation to study stirred vessel hydrodynamics;278
13.3;Chapter 32. Compartmental modelling of an 1100L DTB crystallizer based on large eddy flow simulation;286
14;PART X: POSTERS;296
14.1;Chapter 33. Detailed CFD prediction of flow around a 45° pitched blade turbine;296
14.2;Chapter 34. Comparison of CFD methods for modelling of stirred tanks;304
14.3;Chapter 35. Predicting the tangential velocity field in stirred tanks using the Multiple Reference Frames (MRF) model with validation by LDA measurements;312
14.4;Chapter 36. Numerical simulation of flow of Newtonian fluids in an agitated vessel equipped with a non standard helical ribbon impeller;320
14.5;Chapter 37. A contribution to simulation of mixing in screw extruders employing commercial CFD-software;328
14.6;Chapter 38. Experimental and CFD characterization of mixing in a novel sliding-surface mixing device;336
14.7;Chapter 39. An investigation of the flow field of viscoelastic fluid in a stirred vessel;344
14.8;Chapter 40. Flow of Newtonian and non-Newtonian fluids in an agitated vessel equipped with a non-standard anchor impeller;352
14.9;Chapter 41. Characterization of convective mixing in industrial precipitation reactors by real-time processing of trajectography data;360
14.10;Chapter 42. Characterization of flow and mixing in an open system by a trajectography method;368
14.11;Chapter 43. Characterization of the turbulence in a stirred tank using particle image velocimetry;376
14.12;Chapter 44. Turbulent macroscale of the impeller stream of a Rushton turbine;384
14.13;Chapter 45. Analysis of macro-instabilities (MI) of the flow field in stirred tank reactor (STR) agitated with different axial impellers;392
14.14;Chapter 46. Local dynamic effect of mechanically agitated liquid on a radial baffle;400
14.15;Chapter 47. Interpretation of macro- and micro-mixing measured by dual-wavelength photometric tomography;408
14.16;Chapter 48. Effect of tracer properties (volume, density and viscosity) on mixing time in mechanically agitated contactors;416
14.17;Chapter 49. Mixing, reaction and precipitation : an interplay in continuous crystallizers with unpremixed feeds;426
14.18;Chapter 50. Simulation of a tubular polymerisation reactor with mixing effects;438
14.19;Chapter 51. Mixing equipment design for particle suspension - generalized approach to designing;446
14.20;Chapter 52. Characterization and rotation symmetry of the impeller region in baffled agitated suspensions;454
14.21;Chapter 53. Solids suspension by the bottom shear stress approach;462
14.22;Chapter 54. A phenomenological model for the quantitative interpretation of partial suspension conditions in stirred vessels;470
14.23;Chapter 55. A self-aspirating disk impeller – an optimization attempt;478
14.24;Chapter 56. A novel gas-inducing agitator system for gas-liquid reactors for improved mass transfer and mixing;486
14.25;Chapter 57. Hold-up and gas-liquid mass transfer performance of modified Rushton turbine impellers;492
14.26;Chapter 58. A simple method for detecting individual impeller flooding of dual-Rushton impellers;500
14.27;Chapter 59. Numerical simulation of gas-liquid flow in a parallelepiped tank equipped with a gas rotor-distributor;508
14.28;Chapter 60. Experimental and modelling study of gas dispersion in a double turbine stirred tank;516
14.29;Chapter 61. Local heat transfer in liquid and gas-liquid systems agitated by concave disc turbine;524
14.30;Chapter 62. Effect of the viscosity ratio .d/.c on the droplet size distributions of emulsions generated in a colloid mill;532
14.31;Chapter 63. Experimental measurement of droplet size distribution of a MMA suspension in a batch oscillatory baffled reactor of 0.21 m diameter;540
14.32;Chapter 64. Power consumption in mechanically stirred crystallizers;548
14.33;Chapter 65. Fluid dynamic studies of a large bioreactor with different cooling coil geometries;556
15;Author index;564