1 General: Definitions
In falling-film equipment, a thin film of liquid generally flows downward under gravity on the inner surfaces of vertical tube bundles. Heat is transferred in order to
raise the temperature of the liquid and/or
evaporate some of the liquid.
The heating medium is mostly steam that condenses on the outer surfaces of the tubes. Occasionally, the falling film is cooled by heat removal. Features of falling-film equipment are
high heat transfer coefficients
short residence times
short liquid holdup
low pressure drops.
This chapter presents simple power-law equations for the determination of heat transfer during heating, cooling, and evaporation of falling films. They have been derived from verified compilations of measured values [1]. Three dimensionless numbers suffice for the description of heat transfer, viz.,
the Nusselt number \( \equiv {{\alpha }\over{\lambda }}\left( {{{v^2 }}\over{g}} \right)^{1/3} \)
the Reynolds number \({\mathop{\rm Re}\nolimits} \equiv...
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
5 Bibliography
Schnabel G, Schlünder EU (1980) Wärmeübergang von senkrechten Wänden an nichtsiedende und siedende Rieselfilme. Verfahrenstechnik 14(2):79–83
Nußelt W (1916) Die Oberflächenkondensation des Wasserdampfes. VDI-Zeitschrift 60:542–575
Kapitza PL (1948, 1949) Wellenströmung der dünnen Schichten einer viskosen Flüssigkeit. J Exp Theoret Phys (UdSSR) 18(1):3–18; 19(2):105–120
Brauer H (1956) Strömung und Wärmeübergang bei Rieselfilmen. VDI-Forsch., Heft 457
Kosky P (1971) Thin liquid films under simultaneous shear and gravity forces. Int J Heat Mass Transfer 14:1220–1224
Kutadeladze S Fundamentals of heat transfer. Edward Arnold, London.
Portalsky S (1963) Studies of falling liquid film flow. Chem Eng Sci 18:787–804
Bays GS, McAdams WH (1937) Heat transfer coefficients in falling film heaters. Ind Eng Chem 29(11):1240–1246
Schnabel G (1980) Bestimmung des örtlichen Wärmeüberganges bei der Fallfilmverdampfung und Kondensation an gewellten Oberflächen zur Auslegung von Hochleistungsverdampfern. Diss. Univ. Karlsruhe
Struve H (1969) Der Wärmeübergang an einem verdampfenden Rieselfilm. VDI-Forsch.-Heft 534
Schnabel G, Gnielski V, Schlünder EU (1981) Örtliche Wärmeübergangskoeffizienten bei der Verdampfung von Rieselfilmen an senkrechten, profilierten Oberflächen. Chemie-Ing-Technik 53(3):187–190
Fujita T, Ueda T (1978) Heat transfer to falling liquid film and film breakdown. Int J Heat Mass Transfer 21:97–113
Bressler R (1958) Versuche über die Verdampfung von dünnen Flüssigkeitsfilmen. VDI-Z. 100:630–638
Haase B (1970) Der Wärmeübergang am siedenden Rieselfilm. Chem Technik 22(5):283–287.
Ganić EN, Mastanaiah K (1981) Hydrodynamics and heat transfer in falling film flow, low Reynolds number flow heat exchangers. Hemisphere Publ., pp 487–528
Fujita T, Ueda T (1978) Heat transfer to falling liquid films and film breakdown-I. Subcooled liquids films. Int J Heat Mass Transfer 21:97–108
Fujita T, Ueda T (1978) Heat transfer to falling liquid films and film breakdown-II. Saturated films with nucleate boiling. Int J Heat Mass Transfer 21:109–118
Ganić EN, Roppo MN (1980) A note on heat transfer to falling liquid films on vertical tubes. Lett Heat Mass Transfer 7(2):145–154
Cichelli MT, Bonilla CF (1945) Heat transfer to falling liquids under pressure. Trans. AIChE 41:755
Chen JC, Palen JW (1984) Two-phase flow and heat transfer in process equipment. AIChE-Today-Series. Am Inst Chem Eng
Author information
Authors and Affiliations
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2010 Springer-Verlag
About this entry
Cite this entry
Schnabel, G. (2010). M3 Heat Transfer to Falling Films at Vertical Surfaces. In: VDI Heat Atlas. VDI-Buch. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-540-77877-6_96
Download citation
DOI: https://doi.org/10.1007/978-3-540-77877-6_96
Published:
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-540-77876-9
Online ISBN: 978-3-540-77877-6
eBook Packages: EngineeringReference Module Computer Science and Engineering