Green’s Functions of the Convective Helmholtz Equation for an Infinite Straight Circular Cylinder with Acoustically Rigid and Soft Walls
* Presenting author
Green’s functions of the three-dimensional convective Helmholtz equation for an infinite circular cylinder with acoustically rigid and soft walls are found. These functions are represented by a series of the corresponding cylinder acoustic modes. In the functions, the uniform mean flow effects are reflected in the direct form. The effects become more significant as the flow Mach number increases, causing, in particular, the appearance and further growth of the functions’ asymmetry about the cylinder cross-section in which the point acoustic source is located. And vice versa, the decrease of the Mach number results in the decrease of the effects and, in particular, the decrease of the indicated asymmetry. In the case of flow absence in the cylinder, the obtained Green’s functions are symmetric about the indicated cross-section and coincide with the corresponding Green’s functions for the investigated cylinders, which are available in the scientific literature.