Post on 04-Jun-2018
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification ofHigh Heat Flux
High Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
FLOW BOILING IN MICROCHANNELS
Ajith Krishnan R
Govt. Engineering College Kozhikode
November 27, 2013
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 1 / 32
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification ofHigh Heat Flux
High Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
Contents
1 What is a MicroChannel?
Channel classificationNeed for smaller passages
2 High Heat Flux RemovalClassification of High Heat FluxHigh Heat Flux Removal Technologies
3 Boiling Heat TransferTypes of Boiling Heat Transfer
4 Flow Boiling In MicrochannelsFlow Boiling in a Microchannel
Two Phase FlowFlow Pattern
5 ConclusionConclusion
6 References
References
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 2 / 32
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification ofHigh Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
What is a MicroChannel? Channel classification
Channel classification
Figure: Channel Classification[1]
D is the channel diameter
In the case of non-circular channels D is the minimum
channel dimension
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 3 / 32
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification ofHigh Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
What is a MicroChannel? Need for smaller passages
Need for smaller passages
Figure: Variation of the heat transfer coefficient with channel size forfully developed laminar flow of air and water [1]
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 4 / 32
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification ofHigh Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
What is a MicroChannel? Need for smaller passages
Need for smaller passages
Figure: Variation of pressure gradient with channel size for fullydeveloped laminar flow of air and water [1]
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 5 / 32
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification ofHigh Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
What is a MicroChannel? Need for smaller passages
Need for smaller passages
Dramatic Enhancement in h with a reuction in ChannelSize is Clear
Pressure Gradient increases with reduction in Channel Size
Compactness/AreaDensity= SurfaceAreaVolume
1D
Decrease in channel size(D) cause an increase in AreaDensity or Compactness
Most efficient heat and mass transfer processes occurinside the lungs and kidney, having flow channels havingcapillary dimensions 4
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 6 / 32
Hi h H Fl R l Cl ifi i f Hi h H Fl
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification ofHigh Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
High Heat Flux Removal Classification of High Heat Flux
Classification of High Heat Flux
Heat flux from microprocessors will be a great challenge inthermal managemnt
Electronic devices particularly high power defenceelecronics dissipate 1000W/cm2 and higher
In future 2500W/cm2 could be reached
Classify High Heat Fluxes as:
High Heat Flux(HHF)::102 103W/cm2
Ultra High Heat Flux(UHF)::103 104W/cm2
Extreme Heat Flux(UHF)::>104W/cm2
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 7 / 32
Hi h H t Fl R l Hi h H t Fl R l T h l i
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification ofHigh Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
High Heat Flux Removal High Heat Flux Removal Technologies
High Heat Flux Removal Technologies
Liquid as working medium/ With and with out phasechange
Heat Pipe -Successful heat removal technology
Nano fluids- Emerging technology
Rest of all technologies associated with three basic types ofcoolant flows:
Microchannels
Jet impingement
Sparys
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 8 / 32
Boiling Heat Transfer Types of Boiling Heat Transfer
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification ofHigh Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
Boiling Heat Transfer Types of Boiling Heat Transfer
Types of Boiling Heat Transfer
Figure: Classification of boiling on the basis of the presence of bulkfluid motion[3]
Pool Boiling-in the absence of bulk fluid flow
Flow Boiling or Forced Convection Boiling-in the presence
of bulk fluid flowAjith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 9 / 32
Boiling Heat Transfer Types of Boiling Heat Transfer
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
Boiling Heat Transfer Types of Boiling Heat Transfer
Subcooled and Saturated Boiling
Figure: Classification of boiling on the basis of the presence of bulkliquid temperature [3]
Pool and flow boiling are further classified as subcooledboiling or saturated boiling,depending on the bulk liquidtemperature
Subcooled boiling-the bulk of the liquid is subcooled
Saturated boiling-the bulk of the liquid is saturatedAjith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 10 / 32
Boiling Heat Transfer Types of Boiling Heat Transfer
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
Boiling Heat Transfer Types of Boiling Heat Transfer
Pool Boiling Curve
Figure: Pool Boiling Curve For water at Atmospheric pressure[4]Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 11 / 32
Boiling Heat Transfer Types of Boiling Heat Transfer
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
Boiling Heat Transfer Types of Boiling Heat Transfer
Pool Boiling Regimes
Figure: The Various stages in pool boiling curve[4]
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 12 / 32
Boiling Heat Transfer Types of Boiling Heat Transfer
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
References
References
g yp g
Actual Pool Boiling Curve
Figure: Actual pool boiling curve[3]
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 13 / 32
Boiling Heat Transfer Types of Boiling Heat Transfer
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow BoilingInMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
g y g
Flow Boiling/Convective Boiling
Figure: Regions of Heat Transfer in Convectivel boiling [4]
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 14 / 32
Boiling Heat Transfer Types of Boiling Heat Transfer
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Boiling Map
Figure: Variation of heat transfer coefficient with Quality with
increasing Heat flux as a parameter[4]Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 15 / 32
Flow Boiling In Microchannels Flow Boiling in a Microchannel
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Flow Boiling in a Microchannel
Flow boiling in a channel is nothing but boiling occurringdue the flow of a liquid with certain velocity whose wallsare subjected to heat
Microchannel flows are driven by pumps with mean flowvelocities in the range of few millimeters per second tomany centimeters per second
Flow in microchannels will be mainly laminar
Two Phase flow With Phase Change
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 16 / 32
Flow Boiling In Microchannels Flow Boiling in a Microchannel
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Microchannel Vs Conventional Channel
The 2 phase heat transfer correlations for microchannelsare different from conventional channels
Surface tension forces are more dominant and gravityforces are negligible in microchannels
Separate studies need to be conducted for microchannels
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 17 / 32
Flow Boiling In Microchannels Two Phase Flow
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Basic Definitions and Terminology
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 18 / 32
Flow Boiling In Microchannels Two Phase Flow
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Basic Definitions and Terminology
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 19 / 32
Flow Boiling In Microchannels Flow Pattern
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Need For Identifying The Flow Patterns
Heat tansfer coefficients and pressure drop are closelyrelated to the local two phase flow structure of the fluid
Flow pattern prediction is an important aspect inmodelling evaporation and condensation
Flow pattern depends on the conditions ofpressure,flow,heat flux,and channel geometry
Physical parameters delinating the flow pattern are
Surface tension
Gravity(non vertical channels-stratification)
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 20 / 32
Flow Boiling In Microchannels Flow Pattern
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Flow pattern in vertical tube with out heating
Figure: Two phase flow pattern in vertical up flow[5]
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 21 / 32
Flow Boiling In Microchannels Flow Pattern
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Flow pattern in vertical heated Channels
Figure: Two phase flow pattern in vertical Evaporator Tube[5]
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 22 / 32
Flow Boiling In Microchannels Flow Pattern
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Flow pattern in Horizontal Channels WithoutHeating
Figure: Flow pattern in Horizontal Flow[5]
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 23 / 32
Flow Boiling In Microchannels Flow Pattern
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Flow pattern in Horizontal Heated Tube
Figure: Flow pattern in Horizontal tube With Heating[5]
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 24 / 32
Flow Boiling In Microchannels Flow Pattern
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Flow pattern Map in Horizontal Two PhaseFlow
Figure: Baker Flow Pattern Map for Horizontal Flow in a Pipe[4]
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 25 / 32
Flow Boiling In Microchannels Flow Pattern
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Flow pattern Map in Verticall Two PhaseFlow
Figure: Hewitt and Roberts Flow Pattern Map for Vertical Upflow ina Pipe[4]
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 26 / 32
Flow Boiling In Microchannels Flow Pattern
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Bubble Nucleation
-Nucleation Sites?
Different Routes for Nucleation Deviation from Stable equillibrium Deviation from Metastable equillibrium Deviation from Unstable equillibrium
Figure: Metastable state[4]
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 27 / 32
Flow Boiling In Microchannels Flow Pattern
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Heat Transfer Mechanisms During FlowBoiling In Microchannel
-Nucleate Boiling-HHF and low vapour quality-Convective Boiling-High mass flux and high vapour quality
Figure: Different heat transfer mechanis ms during flow boiling in amicrochannel
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 28 / 32
Conclusion Conclusion
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Conclusion
Fundamental understanding of flow boiling phenomenon inmicrochannel is slowely emerging
Understanding of liquid and vapour phase interactionsduring two phase flow in microchannel have intense
important Surface tension is the dominant force in flow field
Need of an acurate experimental flow boiling data need fordifferent channel types
Flow reversal in multichannels.Rapod expansion of bubblein to slug pushes liquid away both upstream anddownstream of the flow
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 29 / 32
References References
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
References
[1]Satish G. Kandlikar, Srinivas Garimella, Dongqing Li, Stephane
Colin, Michael R. KingHeat Transfer And Fluid Flow In Minichannels And Microchannels
ELSEVIER. First edition 2006
[2]M. A. Ebadian,C. X. Lin
A Review of High-Heat-Flux Heat Removal Technologies
Journal of Heat Transfer,NOVEMBER 2011, Vol. 133/ 110801-1
[3]Yunus A. Cengel
HEAT TRANSFER A Practical Approach
McGraw-Hill. Second edition 2006
[4]John G. Collier, John R. Thome
Convective Boiling and Condensation
Oxford University Press, Third Edition,1994
[5], John R. Thome
Wolverine Engineering Data Book III
Wolverine tube incAjith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 30 / 32
References References
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
References
[6],Kandlikar, S.G.
Heat Transfer Mechanisms During Flow Bo iling in Microchannels
Journal of Heat Transfer,ASME, Vol. 126, pp. 8- 16.
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 31 / 32
Fl b ili i
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Flow boiling inMicrochannels
Ajith KrishnanR
What is a Mi-croChannel?
Channelclassification
Need for smallerpassages
High HeatFlux Removal
Classification of
High Heat FluxHigh Heat FluxRemovalTechnologies
Boiling HeatTransfer
Types of BoilingHeat Transfer
Flow Boiling
InMicrochannels
Flow Boiling in aMicrochannel
Two Phase Flow
Flow Pattern
Conclusion
Conclusion
ReferencesReferences
Thank you
Ajith Krishnan R (GEC KKD) Flow boiling in Microchannels November 27, 2013 32 / 32