investigation of flow distribution in multiple microchannels reporter: zhang weihua supervisor:...
TRANSCRIPT
Investigation of flow distribution in multiple microchannels
Reporter: Zhang WeihuaSupervisor: Professor Xin Feng
I
• Preliminary ideas
II
• Simulate or not?
III
•Experiment methods
IV
•Further plan
Contents
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
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
Shantanu Roy. Experimental investigation of gas–liquid distribution in monolith reactors. Chemical Engineering Science 62 (2007) 7463 – 7470.
III Experiment methods
CTMRI Liquid collecting methodMicro-conductivity probe……
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.
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.
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.
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 intervals2 Dependency on light source3 Deviation existing in estimation of film thickness and measuring of bubble diameter4 Randomly picked 5 channels to represent overall performance
III Experiment methods
1 Choice of multiple microchannel
Capillary or honeycomb ceramic
2 Channel shape Round or square3 Channel arrangement Radial pattern or…4 Accessories Plexiglass cylinder, pipe5 Measurement CT, MRI or Cai’s method
Questions list
III Experiment methods
Parameters preferred:Monolith element diameter: 10mmMonolith element length: 50 mmChannel diameter: 0.1-1mmSuperficial velocity: ug 0.08m/s, ul 0.1m/s Sample time: 100 periodsSample channel number: tmtb
III Experiment methods
{hGas holdup or
Maldistribution
Critical dimensions
Entrance effect
Gas/liquid superficial
velocity
IV Further plan
1. Jul to Aug: Experiment2. Sep to Oct: CFD simulation3. Simulate multichannel cases by Monte
Carlo or Chaotic Theories?4. Proposal of dividing line
Thank you !Da
nke