1 me421 heat exchanger design drain water heat recovery system project presentation group #5
TRANSCRIPT
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ME421 Heat Exchanger ME421 Heat Exchanger DesignDesign
Drain Water Heat Recovery Drain Water Heat Recovery SystemSystem
Project PresentationProject Presentation
Group #5Group #5
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OUTLINEOUTLINE
Problem DefinitionProblem Definition Available SolutionsAvailable Solutions Proposed SolutionProposed Solution Application DataApplication Data Solution ProcedureSolution Procedure Results and DiscussionsResults and Discussions ConclusionConclusion
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AVAILABLE SOLUTIONSAVAILABLE SOLUTIONS
Gravity Film Heat Exchanger(GFX)Gravity Film Heat Exchanger(GFX)
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PROPOSED SOLUTIONPROPOSED SOLUTION
Gasketed Plate Heat Exchanger:Gasketed Plate Heat Exchanger: High Area/Volume RatioHigh Area/Volume Ratio Low Cost compared to GFXLow Cost compared to GFX Easy to cleanEasy to clean Flexible DesignFlexible Design
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APPLICATION DATAAPPLICATION DATAParameterParameter MagnitudeMagnitude Unit (SI)Unit (SI)
Hot Inlet Temperature Hot Inlet Temperature 3737 °C°C
Hot Outlet TemperatureHot Outlet Temperature 2323 °C°C
Cold Inlet TemperatureCold Inlet Temperature 1111 °C°C
Cold Outlet TemperatureCold Outlet Temperature 2525 °C°C
Cold Water Mass Flow RateCold Water Mass Flow Rate 0.20.2 kg/skg/s
Hot Water Mass Flow RateHot Water Mass Flow Rate 0.20.2 kg/skg/s
Hot Side Fouling FactorHot Side Fouling Factor 0.000050.00005 m.K/Wm.K/W
Cold Side Fouling FactorCold Side Fouling Factor 0.00000860.0000086 m.K/Wm.K/W
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SOLUTION PROCEDURESOLUTION PROCEDURE
Initial Assumptions:Initial Assumptions:
Steady state and steady flow processesSteady state and steady flow processes Plate dimensions based on MIT 522 Plate dimensions based on MIT 522
[1] [1]
LLvv, L, Lhh, b, t, D, b, t, Dpp, , ββ, , ΦΦ
Negligible potential and kinetic energy changeNegligible potential and kinetic energy change Equal inlet & outlet mass flow ratesEqual inlet & outlet mass flow rates Single pass counter flow arrangementSingle pass counter flow arrangement Safety factorSafety factor
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SOLUTION PROCEDURE SOLUTION PROCEDURE (Cont’d)(Cont’d)
Procedure:Procedure: Iteration method to find NIteration method to find Ntt
U AU Aee N Ntt G Re Nu h U G Re Nu h U Rechecking of NRechecking of Ntt using calculated U using calculated U Pressure drop and pump power calculationsPressure drop and pump power calculations Comparison of Comparison of ΔΔPPlimitlimit and and ΔΔPPcalculatedcalculated
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RESULTS and DISCUSSIONSRESULTS and DISCUSSIONS
Nt ranging between 3 and 11
Pre
ssur
e D
rop
(Pa)
Pressure Drop vs Number of Plates (Nt)
2 3 4 5 6 7 8 9 10 11 127.2 10
4
7.3 104
7.4 104
7.5 104
7.6 104
7.7 104
7.8 104
7.9 104
8 104
p t.c
p t.h
Nt
1010
RESULTS and DISCUSSIONS RESULTS and DISCUSSIONS (Cont’d)(Cont’d)
20 27.5 35 42.5 50 57.5 65 72.5 806 10
3
7.75 103
9.5 103
1.125 104
1.3 104
1.475 104
1.65 104
1.825 104
2 104
Qc W( )
Qf W( )
β values : 30 ° ,45 ° ,50 ° ,60 ° ,65°
Hea
t R
ecov
ery
(W)
Heat Recovery vs Chevron Angle (β)
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RESULTS and DISCUSSIONS RESULTS and DISCUSSIONS (Cont’d)(Cont’d)Pum
p P
ow
er
(W)
Nt ranging between 3 and 11
Pump Power vs Number of Plates (Nt)
Pum
p P
ow
er
(W)
Pump Power vs Number of Plates (Nt)
Pum
p P
ower
(W
)
2 3 4 5 6 7 8 9 10 11 1224.5
24.833
25.167
25.5
25.833
26.167
26.5
Wp
Nt
1212
RESULTS and DISCUSSIONS RESULTS and DISCUSSIONS (Cont’d)(Cont’d)
β values : 30 ° ,45 ° ,50 ° ,60 ° ,65°
Pre
ssu
re D
rop (
Pa)
Pressure Drop vs Chevron Angle (β)
20 30 40 50 607.3 10
4
7.35 104
7.4 104
7.45 104
7.5 104
p t.c
p t.h
1313
RESULTS and DISCUSSIONS RESULTS and DISCUSSIONS (Cont’d)(Cont’d)
ParameterParameter MagnitudeMagnitude
Number of PlatesNumber of Plates 77
Effective Heat Transfer AreaEffective Heat Transfer Area 1.463 m1.463 m22
Fouled Heat Transfer CoefficientFouled Heat Transfer Coefficient 933 W/m933 W/m22.K.K
Required Pump WorkRequired Pump Work 24.5 W24.5 W
Heat Transfer RateHeat Transfer Rate 1.171.17xx101044 W W
Net Heat RecoveryNet Heat Recovery 1.171.17xx101044 W W