50 



MYDRODYNAMK-S IN SHIP DESIGN 



Sec. 42.14 



opposite plato plus that being fed into the foil, 

 between the plates. In diagram 4 of Fig. 42. H, 

 traced from one published by H. Fottingcr [STG, 

 1924, Fig. 43, p. 338], the foil i.s replaced by a 

 small heart-shaped botly and the flow resembles 

 (hat delineatetl for the Magnus Effect in Fig. 14. E. 

 An auxiliary direct current of the proper amount 

 is fed into the body. This is easily done by con- 

 necting it to the source that supplies the row of 

 positive electrodes, and interposing a variable 

 resistance in the circuit of the body. The current 

 from the botly flows in the manner shown toward 

 the row of negative electrodes. It pushes aside, 

 as it were, the current paths from the row of 

 positive electrodes. This setup produces equi- 

 potential lines which are actually the streamlines 

 of a combination of counter-clockwise circulatory 

 flow around the body and a streamline flow from 

 (he right; see Figs. 14. E and 14. F. 



The electrolytic-tank technique has now ex- 

 panded and developed to the point where it needs 

 its own book. All that can be done here is to 

 give a hst of the principal references so far 

 unearthed, in generally chronological order, and 

 leave the reader to further study by himself. 

 Comments are appended to some of the references. 



42.14 Bibliography on the Electric Analogy for 

 Flow Patterns. In tlii.s section there arc listed 

 a number of the principal references to the rather 

 extensive literature on the employment of the 

 electric analogy for delineating streamline, equi- 

 potential, and other flow patterns. 



(1) Relf, E. F., "An Electrical Method of Tracing 

 Streamlines for the Two-Dimensional Motion of a 

 Perfect Fluid," Phil. MaR., Sep 1924, Vol. 48, pp. 

 535-539; sec al.so ARC, R and M 905, 1924 



(2a) Taylor, G. I., and Sharman, C. F., 'Troblcma of 

 Flow in Compressible Fluids," Proc. Roy. Soc, 

 Ix)ndon, Scries A, 1928, Vol. 121; also ARC, R and 

 M 1195, AuR 1928 



(2h) Taylor, O. I., "The Flow Round a Body MovinR in 

 a Comprc-f-silile Fluid," Pror. Third Int. ConR. 

 Appl. Mcch., Stockholm, 1930, Vol. I, pp. 203 275, 

 cap. pp. 205-272 



(3) Koch, J. J., "Fine Expcrimcntcllo Methotic zur 



Bcxtimmung der Reduziertcn Masse dcs Mit- 

 schwinRenden Wasscrs Dei SchilTsschwingunRcn 

 {Exfwrimcntjil Metho<l for DctermininR the Virtual 

 Maw) for Cjsrillations of Ships)," lnR.-.\rchiv, 

 1033, Vol. IV, Part 2, pp. 103-109; TMH Transl. 

 225 of May 10-19 



(4) Malavard, I.., "Application dea analogies ^Icctriquea 



h lu iHihitiun do (|Uclr|u<-fl prold^mes dc I'liydro- 

 dyiinmic (A|iplicatiun of Eleclriral AnuloRicji to 

 the Solution of Some Ilydrodynaniic ProWcms)," 



Publ. Sci. et Tech., Min. de I'.Vir, Paris, No. 57, 

 1934 



(5) Salct, G., "D6tennination dcs pointcs do tension 

 dans lea arbrca de revolution sourais ii torsion au 

 moyen d'un module 6lcctrique (Determination of 

 Tcn.sile Stress in RevolvinR Shii/ts under a Tor- 

 sional Load, by Means of an Electric Model)," 

 .VTMA, 1930, Vol. 40, pp. 341-351. Thia paper 

 illustrates and describes an electrolytic tank which 

 is, in effect, a 3-diml affair, inasmuch as the body 

 in the tank hits varied depths of electrolyte over it. 



(0) P6r&i, J., and Malavard, L., ".\pplication du bassin 

 flectrique i\ quelques questions de mecanique dcs 

 fluidos (The .\pplication of Electric Flow in Liquids 

 to Some Questions of the Mechanics of Fluids)," 

 ATMA, 1938, Vol. 42, pp. 529-541. This paper, 

 so far as known, is not translated into English. A 

 number of references are listed on pp. 529, 531, 

 and 534. 



The authors go into the question of the use of 

 the electrolytic tank for flow problems involving 

 circulation. 



In the same volume, in a paper by iRonet, 

 Plate 3 on p. 551, there is shown a group of equi- 

 potcntial spots for a 3-diml Rankine ellipsoid. 



(7) Malavard, L., "fitude de quelque probl6mes reU'vant 

 de la thforie dcs ailcs. .\pplication ii Icur solution 

 de la mcthode rh6o61cctrique (Study of Problems 

 Relevant to the Theory of Wings. Application of 

 (he Rheo-Electric Method to Their Solution)," 

 Publ. Sci. et Tech., Min. de I'Air, Paris, No. 153, 

 1939 



(S) Peres, J., and Malavard, L., "Rlieographic and 

 Rheometric Analog Methods," (in French), Bull. 

 Soc. Fr. Elec, 1939, Vol. 8, pp. 715-744 



(9) Malavard, L., and P^ri^s, J., "Tables numfiriques 

 pour Ic caloul de la rtpartition des charges aCro- 

 (lynumiqucs sur I'envcrRurc d'uiie aile (Numerical 

 Tables for the Calculation of the Distribution of 

 .\crodynamic I^oada On the Span of a Wing)," 

 Tech. Rep. 9, Group. Frangais pour les Rtcherches 

 Aero., 1943 



(10) Malavard, L., "Sur la solution rh6o61ectrique do 



questions dc representation conforme et application 

 ,^ la th^'oric des prolils d'ailcs (On the Rhco-Electric 

 Solulioii of Questions of Conformal Representation 

 and .Application to the Theory of Wing Profiles)," 

 Compte.s-Rendus, .\cad. Sci., Paris, Jan 1944 



(11) Sicstninck, R., "Sur un mode de solution rhfo- 



<''lcrlri<iue dv* problemcs <lc rhf'liie propulsive 

 (On a Rheo-Electric Method of Solution of Screw- 

 Propeller Problema)," Comptcs-Rcndua, Acad. Sci., 

 Paris, Sep 1914 



(12) Malavard, L., and Sicstrunck, R., "Sur unc melhodo 



dY-tude des grilles ind^fmics de prolils quclconquea 

 (On a Method of Study of llnderined Flow Nets 

 Around any Profde)," Cong. Nat. Aviat. Franfftise, 

 Apr 1945 



(13) Malavard, L., "Application afrodynamique de ejdcul 



oxp^rimontal analoRique (.\erodynamic Applica- 

 tion of ExiHirinientid .\nal<iR.v t'alrulalions)," 

 Cong. Nat. Aviat. Franc^aiw, Apr 1945 



(14) .Malavard, L., "Calculatcur d'aiica ul rOscau do 



