1. Investigation of flow distribution in multiple microchannels Reporter: Zhang Weihua Supervisor: Professor Xin Feng

2. I Preliminary ideas II Simulate or not? III Experiment methods IV Further plan Contents

3. I Preliminary ideas 1. Explore the specified diameter obtained based on simulation and experiment results, when acceptable distribute performance 2. Search for possible regular pattern from single channel to multiple channels via probabilistic model 3. Propose advisable dividing line between microchannel and macrochannel

4. II Simulate or not? CFD simulation was laid aside due to unsatisfying grid and low performance PC Necessity of CFD simulation: asymmetry structure, radial nonuniformity

5. Shantanu Roy. Experimental investigation of gas–liquid distribution in monolith reactors. Chemical Engineering Science 62 (2007) 7463 – 7470. III Experiment methods CT MRI Liquid collecting method Micro-conductivity probe ……

6. III Experiment methods W. Cai et al. Experimental Investigation of Gas Holdup and Slug Lengths in an Upflow Monolith Reactor. Chem. Eng. Technol. 2011, 34, No. 6, 955–962.

7. III Experiment methods W. Cai et al. Experimental Investigation of Gas Holdup and Slug Lengths in an Upflow Monolith Reactor. Chem. Eng. Technol. 2011, 34, No. 6, 955–962.

8. III Experiment methods W. Cai et al. Experimental Investigation of Gas Holdup and Slug Lengths in an Upflow Monolith Reactor. Chem. Eng. Technol. 2011, 34, No. 6, 955–962.

9. III Experiment methods W. Cai et al. Experimental Investigation of Gas Holdup and Slug Lengths in an Upflow Monolith Reactor. Chem. Eng. Technol. 2011, 34, No. 6, 955–962. Some places to be improved: 1 Narrow adaptable intervals 2 Dependency on light source 3 Deviation existing in estimation of film thickness and measuring of bubble diameter 4 Randomly picked 5 channels to represent overall performance

10. III Experiment methods 1Choice of multiple microchannel Capillary or honeycomb ceramic 2Channel shapeRound or square 3Channel arrangementRadial pattern or… 4AccessoriesPlexiglass cylinder, pipe 5MeasurementCT, MRI or Cai’s method Questions list

11. III Experiment methods Parameters preferred: Monolith element diameter: 10mm Monolith element length: 50 mm Channel diameter: 0.1-1mm Superficial velocity: u g 0.08m/s, u l 0.1m/s Sample time: 100 periods Sample channel number: tmtb

12. III Experiment methods ｛ h Gas holdup or Maldistribution Critical dimensions Entrance effect Gas/liquid superficial velocity

13. IV Further plan 1.Jul to Aug: Experiment 2.Sep to Oct: CFD simulation 3.Simulate multichannel cases by Monte Carlo or Chaotic Theories? 4.Proposal of dividing line

14. Thank you ！ Danke