Abstract
The present paper deals with the two-dimensional flow field around a circular cylinder moving slowly along the central plane parallel to side planes in a viscous liquid bounded by two parallel side planes. It is solved semi-analytically by applying the collocation method for the determination of unknown coefficients of the general solution. From the stream function determined, experssions of velocity, pressure and viscous stress are obtained and are discussed on the basis of numerical results. It seems to be quite all right to consider the present solution to be reasonable. The pressure drag and the friction drag of the cylinder are determined from the pressure distribution and the viscous stress distribution at the surface of a circular cylinder, respectively. It is shown that the pressure drag is larger than the friction drag and the ratio of the former to the latter decreases with an increase in the distance between two parallel planes. Concerning the total drag of a circular cylinder, Faxen's formula about the two parallel planes effect on the drag is discussed on the present analytical results and a modified formula is proposed. The new formula is useful in a wider range of the distance between two parallel planes.
