The forces on a solid body moving through viscous fluid

Abstract

In a previous paper with the same title a general theorem was stated concerning the resultant force on a solid body of any size and shape moving with uniform velocity U through otherwise still fluid of density ρ . The discussion then given was not sufficiently general. This was pointed out to me by Professor Burgers, to whom I wish to express my thanks for the great interest he has shown in the matter. My thanks are also due to Dr. Jeffreys for valuable criticisms of the first draft of this paper, which has been largely rewritten in consequence. In the previous discussion the equations (P. 4) give the solution only when the solid body is of revolution, and they are not sufficiently general. To recognise this, it is sufficient to note that they give no component of vorticity about the direction of the stream.