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Heat and Mass Transfer

, Volume 43, Issue 8, pp 843–848 | Cite as

Gas absorption in a thin liquid film flow on a horizontal rotating disk

  • G. PeevEmail author
  • D. Peshev
  • A. Nikolova
Original

Abstract

An analytical model for the rate of gas absorption into laminar non-wavy film flow on a horizontal rotating disk is obtained assuming short contact times. Literature data for the oxygen mass transfer coefficient in a wavy film is correlated by means of the dimensionless numbers deriving from the model. The rate enhancement due to waves is found to vary from 6 to 13 times. It is established that the absorption process in the film on the disk as compared to that in a gravitational wavy film flow can be intensified up to 14 times by means of a moderate rotation speed.

Keywords

Mass Transfer Coefficient Sherwood Number Film Flow Short Contact Time Ekman Number 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

List of symbols

C

solute concentration, kg m−3

Cn

eigenfunction

D

diffusivity, m2 s−1

E

Ekman number, \( E = \nu \mathord{\left/{\vphantom {\nu {\omega r^{2}}}} \right.\kern-\nulldelimiterspace} {\omega r^{2}}\)

\({\overline K} \)

average mass transfer coefficient, Eq. 15, m s−1

M(a,b,c)

confluent hypergeometric function

N

local mass transfer rate, kg m−2 s−1

\({\overline N}\)

mean integral mass transfer rate, kg m−2 s−1

Q

volumetric flow rate, m3 s−1

R

radius of the disk, m

r

radial coordinate, m

Re

Reynolds number, \(Re = Q \mathord{\left/{\vphantom {Q {2\pi r\nu}}} \right.\kern-\nulldelimiterspace}{2\pi r\nu}\)

\({\overline{Re}}\)

mean integral Reynolds number on the absorbing film surface, Eq. 22

Sc

Schmidt number, \({Sc = \nu \mathord{\left/{\vphantom {\nu D}} \right.\kern-\nulldelimiterspace} D}\)

\({\overline{{Sh}}}\)

mean Sherwood number, Eqs. 16 or 17

w

fluid velocity, m s−1

Y

dimensionless axial coordinate, Eq. 4b

y

axial coordinate, m

Z

dimensionless complex variable, Eq. 4d

Greek symbols

δ

height of the liquid film, m

λn

eigenvalue

ν

kinematic viscosity, m2 s−1

ω

angular disk velocity, rad s−1

ξ

dimensionless radial coordinate, Eq. 4c

ψ

dimensionless concentration, Eq. 4a

Subscripts

in

at the entrance

o

at the film surface

out

at the exit

b

bulk (mixed mean)

s

at the position of sampling

rot

in the field of rotation

grav

in the field of gravitation

References

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Copyright information

© Springer-Verlag 2006

Authors and Affiliations

  1. 1.Department of Chemical EngineeringUniversity of Chemical Technology and MetallurgySofiaBulgaria

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