Hydrodynamic influence of the propeller on a deeply submerged submarine¹

Article type: Research Article

Authors: Hunziker, Raul R.^{; *}

Affiliations: Reed Research, Inc., Washington, D.C.

Note: [1] The results presented in this raper were obtained in the course of research sponsored by the Navy Department, Contract NOnr 1455(00), Project NS-715-102, administered by the David Taylor Model Basin.

Note: [*] Chief Mathematics Branch, Research Division. (Now with Convair, A Division of Gen. Dynamics Corp., San Diego, Calif.)

Abstract: The hydrodynamic interference of a hull-propeller combination moving at a great depth under the free surface is analyzed. On the basis of Oseen’s form of the motion equations, Euler’s theorem and Lagally’s exterior theorem (1922) for a potential stream with singularities a general formula for the thrust deduction fraction is derived. It is shown that the corresponding velocity field contains a system of helical vortices shed by a propeller of an infinite number of blades. In the limiting case of very light loading, the thrust deduction expression is reduced to a generalization of Fresenius’ expression (1921). Numerical values for different configurations of a prolate ellipsoid hull and propeller are presented in tabular form. The results indicate that the thrust deduction fraction exhibits a rapid diminution with the increase of the distance of the propeller from the stern and with the increase of the propeller diameter. These theoretical results are in complete agreement with experimental values measured by Weitbrecht (1941).

DOI: 10.3233/ISP-1958-54403

Journal: International Shipbuilding Progress, vol. 5, no. 44, pp. 166-177, 1958