TP Data Table Flow

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    Department of Metallurgical Engineering and Materials Science

    IIT BombayFormulas/Charts for Transport Phenomena Course

    Newton’s law of Viscosity

    τ yx  = −µdvx

    dy  (1)

    Mechanical Energy Balance

    1

    2

    v22β 2− 1

    2

    v21β 1

    + g(z2 − z1) + 

      2

    1

    1

    ρ

    dP  +  Ŵ  +  Ê f   = 0   (2)

    ˆE f   = 2

    L

    Dv

    2

    f F    (3)

    Fanning friction factor chart for pipe flow [1]

    Figure 1: Fanning friction factor chart for pipe flow [1]

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    Expressions: Fanning friction factor for pipe flow

    Laminar Flow (approximately upto Re 2000)

    f F   =  16

    ReD(4)

    Turbulent Flow

    Colebrook correlation

    1√ f F 

    =   −4log

      1

    3.7

    D +

      1.255

    ReD√ f F 

      Turbulent flow, for ReD  > 4000   (5)

    Churcill Correlation

    1√ f F 

    =   −4log

    0.27 

    D +

      7

    ReD

    0.9  Turbulent flow, for ReD  > 4000(6)

    Blasius equation for hydraulically smooth pipes

    f F    =  0.0791

    Re0.25DTurbulent flow, Smooth Pipes, for ReD  

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    Equivalent Pipe Length to Diameter Ratio for some Common Pipe Fittings

    (Turbulent Flow) [2]Pipe Fitting   LeD

    Globe Valve, wide open   ∼ 300Angle Valve, wide open   ∼170Gate Valve, wide open   ∼ 7

    3/4 open   ∼ 401/2 open   ∼ 2001/4 open   ∼ 900

    90o Elbow, standard 30

    long radius 20

    45o Elbow, standard 15

    Tee, used as elbow, entering the stem 90

    Tee, used as elbow, entering one of two side arms 60

    Tee, straight through 20180o close return bend 75

    Ordinary entrance (Pipe flush with the wall of the vessel) 16

    Borda entrance (Pipe protruding into vessel) 30

    Rounded entrance, union, coupling Negligible

    Sudden enlargement from d to D

    Turbulent flow in d   14f F,ind

    1−   d2

    D2

    2Sudden contraction from D to d

    Turbulent flow in d   110f F,ind

    1.25−   d2

    D2

    Flow Through Packed Bed

    ∆P

    L  =

      150µ(1− ε)2D2 pε

    3  v0 +

     1.75ρ(1− ε)ε3D p

    v02

    D p  =  φ ×DsphDsph  =   Diameter of sphere having the same volume as that of the particle

    φ = Surface area of the sphere having equivalent volume of the particle

    Surface area of the particle

    Fluidized Bed

    ∆PA   =   AL(1− εmf )(ρs − ρ)g

    =   AL

    150.0µ(1− εmf )2

    D2 pε3

    mf 

    vmf  + 1.75ρ(1− εmf )

    ε3mf D pvmf 

    2

    At minimum fluidization, voidage in the bed is given by

    1

    φε3mf ≈ 14   or   1− εmf 

    φ2ε3mf ≈ 11

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    Dsphvmf ρµ

      =

    33.72 + 0.0408D3

    sphρ(ρs − ρ)gµ2

    0.5 − 33.7Voidage in the bed beyond minimum fluidization is given by

    v0  =  εm

    where the exponent, m  is obtained from a plot of  ReDp  vs. m  and is given in Figure 3

    [3].

    Figure 2: Exponent m  in correlation for bed voidage in particulate fluidized bed [3]

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    Flow Pass a particle

    beginequation* FDrag  = A 12ρv

    2

    ∞f 

    Figure 3: Fanning friction factor for flow pass sphere

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    References

    [1] R. Perry and D. Green, Chemical Engineers Handbook . McGraw-Hill, New York,USA, 8th ed., 2008.

    [2] O. Levenspiel, Engineering Flow and Heat Exchange. Plenum Press, New York,

    USA, 1984.

    [3] M. Leva, Fluidization. McGraw-Hill, New York, USA, 1959.

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