Showing papers on "Added mass published in 1973"

Translatory accelerating motion of a circular disk in a viscous fluid

Abstract: The exact solution of the equation of motion of a circular disk accelerated along its axis of symmetry due to an arbitrarily applied force in an otherwise still, incompressible, viscous fluid of infinite extent is obtained. The fluid resistance considered in this paper is the Stokes-flow drag which consists of the added mass effect, steady state drag, and the effect of the history of the motion. The solutions for the velocity and displacement of the circular disk are presented in explicit forms for the cases of constant and impulsive forcing functions. The importance of the effect of the history of the motion is discussed.

Application of the Hypercircle Method to Estimating the Transverse Added Mass of Two-Dimensional Bodies in Restricted Waters

Abstract: In this paper, the author describes a practical method, that is called the hypercircle method, of estimating the transverse added mass of two-dimensional bodies moving in restricted waters. This method is one which rather assesses the upper and lower bounds of the added mass than to calculate the added mass itself directly. However, in order that this method may be available in engineering applications, it is necessary for the upper and lower bounds to be near to each other. Hence, some illustrative calculations of the upper and lower bounds were conducted for the two-dimensional bodies with the sectional form of simple geometry, to say for some rectangular cylinders and a triangular one. Consequently, this method proved to be very useful in case of the rectangular cylinder, while this was not true of the case of the triangular cylinder because of the great difference between the assessed upper and lower bounds. On the other hand, however, it was found by comparing the bounds calculated by this method between the added mass obtained by other method, that is the finite element method, that the lower bound itself could give a good approximate value of the added mass.

Bottom and surface proximity effects on the added mass of Rankine ovoids.

Abstract: The free-surface and bottom-proximity effects on the added mass of Rankine ovoids of various length-to-diameter ratios were experimentally investigated by vertically oscillating the ovoids normal to their major axis. The results have shown that the bottom-proximity increases the added mass and the free-surface proximity decreases it. Furthermore, the added mass increases with increasing lengthto-diameter ratio, i.e., for more cylinder-like ovoids, and approaches that predicted analytically for an infinitely long cylinder. Finally, an appropriate analysis based on the strip-method and the cylinder results has shown that the bottom-proximity effect on the added mass of Rankine ovoids may be predicted with sufficient accuracy. The prediction of the surface-proximity effect requires more refined methods.

Approximate calculation of the added mass in flow around a multirow array of rods

Abstract: A method of calculating effective masses of multirow clusters of elastic-cylindrical rods is presented. The flow of liquid caused by lateral vibrations of the rods is described approximately using a model of cells.