Forces due to exterior singularities upon 2- and 3-dimensional bodies

Thrust deduction, or the resistance increase, is not fully investigated probably because of the complexity of the flow pattern in the stern region. In this work, it is assumed that the theory of potential flows may represent the most significant portion of the physics of the phenomena. Hence the propulsor and other devices in the stern region are represented by exterior singularities and their effects upon the resistance increase are estimated by taking a circular cylinder and a sphere as the 2- and 3-dimensional body, respectively. Results for a circular cylinder are summarized, and those for a sphere are given more attention.