Hydromechanics of Propulsion for Ciliated MicroOrganisms
CaltechAUTHORS
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Title 
Hydromechanics of Propulsion for Ciliated MicroOrganisms


Creator 
Brennen, Christopher


Subject 
Caltech Library Services


Description 
To the present time much of the hydrodynamic analysis of the locomotion of ciliated microorganisms has concentrated on the localized interaction between the cilia and the fluid medium. In doing so most investigators have found it necessary to simplify the larger scale flow and to consider "infinite sheet models" in which the fluid flow solutions are purely harmonic and the wave properties invariant in the rectilinear coordinate parallel to the sheet. The resulting mean motion is purely unidirectional and thus the hydrodynamic solution greatly simplified. Since these "infinite sheet models" conveniently termed the "envelope" and "sublayer" models are discussed in detail by Blake and Sleigh (1974a, b) elsewhere in this volume further amplification is unnecessary. It is convenient, however, for our purposes to think of these as fluid/cilia interaction models describing the local interaction between the cilia and the fluid. The relative merits of the two types of model and criteria which describe their respective region of validity are discussed by Brennen (1974) and by Blake and Sleigh (1974b). In the present paper we will discuss some of the characteristics of the flow around "finite" ciliated microorganisms, pointing out along the way those effects not experienced in the infinite sheet models but which are important in evaluating, say, the propulsive velocity of a ciliated microorganism. The only previous solution for a "finite" body to appear in the literature seems to be that of Lighthill (1952), later modified by Blake (1971a) in which traveling surface waves on a sphere (to use the "envelope" model) are approximated by combining two spherical harmonic functions whose orders differ by one. But this solution is very restrictive in terms of the permitted variation of waveform and wave amplitude over the body and its extension to nonspheriodal bodies would involve prohibitive algebraic complexity. 

Publisher 
Plenum Press


Contributor 
Wu, Theodore Y.T.
Brokaw, Charles J. Brennen, Christopher 

Date 
1975


Type 
Book Section
PeerReviewed 

Format 
application/pdf


Identifier 
http://authors.library.caltech.edu/186/1/BRE022.pdf
Brennen, Christopher (1975) Hydromechanics of Propulsion for Ciliated MicroOrganisms. In: Swimming and Flying in Nature. Plenum Press , New York, pp. 235253. ISBN 0306370883 http://resolver.caltech.edu/CaltechAUTHORS:BREsfn75 <http://resolver.caltech.edu/CaltechAUTHORS:BREsfn75> 

Relation 
http://resolver.caltech.edu/CaltechAUTHORS:BREsfn75
http://authors.library.caltech.edu/186/ 
