The Inertia Coefficients of an Airship in a Frictionless Fluid

Description: The apparent inertia of an airship hull is examined. The exact solution of the aerodynamical problem is studied for hulls of various shapes with special attention given to the case of an ellipsoidal hull. So that the results for the ellipsoidal hull may be readily adapted to other cases, they are expressed in terms of the area and perimeter of the largest cross section perpendicular to the direction of motion by means of a formula involving a coefficient kappa which varies only slowly when the shape of the hull is changed, being 0.637 for a circular or elliptic disk, 0.5 for a sphere, and about 0.25 for a spheroid of fineness ratio. The case of rotation of an airship hull is investigated and a coefficient is defined with the same advantages as the corresponding coefficient for rectilinear motion. Bateman, H. December 1, 1979 UNT Libraries Government Documents Department National Advisory Committee for Aeronautics Collection Technical Report Archive and Image Library Total Uses: 212 Past 30 days: 1 Yesterday: 0
Creator (Author): Creation: December 1, 1979 The apparent inertia of an airship hull is examined. The exact solution of the aerodynamical problem is studied for hulls of various shapes with special attention given to the case of an ellipsoidal hull. So that the results for the ellipsoidal hull may be readily adapted to other cases, they are expressed in terms of the area and perimeter of the largest cross section perpendicular to the direction of motion by means of a formula involving a coefficient kappa which varies only slowly when the shape of the hull is changed, being 0.637 for a circular or elliptic disk, 0.5 for a sphere, and about 0.25 for a spheroid of fineness ratio. The case of rotation of an airship hull is investigated and a coefficient is defined with the same advantages as the corresponding coefficient for rectilinear motion. aerodynamics NASA. Ames Res. Center Classical Aerodyn. Theory; p 161-174 Originator : California Inst. of Tech. NACA Technical Reports UNT Libraries Government Documents Department National Advisory Committee for Aeronautics Collection Technical Report Archive and Image Library LOCAL-CAT-Number: 80N15042 URL: http://hdl.handle.net/2060/19800006783 REP-NO: NACA-TR-164 CASI: 19800006783 ARK: ark:/67531/metadc53406 Report Text Access: Public License: Public Domain Statement: No Copyright, Unclassified, Unlimited, Publicly available