MICROCHANNEL HEAT EXCHANGER PREPARED BY ANAND R.NADGIRE F.Y.M.Tech(MIS No. 121025015) 2010-11
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
Miniaturization & microchannel concept Miniaturization :Process of making something very small using modern technology Microchannels :Micro refers to something small than usual considering particular scale Channels refer to age of flow
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
OVERVIEW Microchannel exchanger definition Manufacturing of Microchannel Hex Performance parameters and comparison Microchannel technology advantages Implementation Challenges
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
Microchannel consideration : Mehandale etal : Flow in of ‘channel dimension’ Cd 1 μm < CD < 100 μm :
Microchannels
100 μm < CD <1 mm : Minichannels 1 mm < CD < 6 mm : Compact ages 6 mm < CD : Conventional ages
Obet : Flow in of ‘hydraulic diameter’ Dh
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
Microchannel Hex definition
MICR OCHANNEL HEAT EXCHANGER F.Y.M.Tech(C.O.E.)
Manufacturing of mHex
MICR OCHANNEL HEAT EXCHANGER F.Y.M.Tech(C.O.E.P)
Performance: Higher heat transfer coefficients
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
mHex performance comparison
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
Performance : Manageable pressure drop
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
Performance : Increased volumetric heat flux
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
Advantages : Higher performance High volumetric heat flux Modest pressure drop Compact hardware for space critical application Robust design Proven manufacturing process Demonstrated mechanical integrity Scalable technology Repeatable design Effective flow distribution MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
Implementation challenges Cost Reliability
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
Cost : Overall cost determined by Equipment costs Installation costs Process productivity Attractive costs for application that Require expensive material of construction, e.g. nickel allot steel ,alluminium Involve multiple streams Demand close approach temperature
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
Reliability : Three performance aspects impact reliability Fouling/plugging Service Particulate size Surface chemistry Solid content Corrosion On-stream factor Frequency of servicing Maintenance access MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
Conclusion : Microchannel provide high heat transfer coefficient because of their small hydraulic diameter Though the implementation method is costly but its performance allow to use it effectively Reduction in mass and volume allows it to use in various applications
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
Future work Thermal view of the microchannel heat exchanger
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
References www.velocys.com R.K.Shah & D.P.Sekulic ,Fundamental of heat exchanger design, John Wiley & sons,2003. D.B.Tuckermann,R.F.W.Pease,High performance heat sinking for VLSI,IEEE electron device letters. N.T.Obet,”Towards the better understanding of friction and heat/mass transfer in microchannel – Literature review” ,Microscale thermo physical engg. www.nasa.gov MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)
MICROCHANNEL HEAT EXCHANGER
F.Y.M.Tech(C.O.E.P)