A displacer for an engine includes a body extending along a displacer longitudinal axis from a displacer first end surface to a displacer second end surface. At least one channel extends between a first opening in the displacer first end surface and a second opening in the displacer second end surface and has sidewalls therebetween defining a channel flow path. The first opening is located at a first radial distance from the displacer longitudinal axis in a first radial direction and the second opening is located at a second radial distance from the displacer longitudinal axis in a second radial direction. At least a portion of the channel flow path has a component in an angular direction that is at an angle to both the first and second radial directions.

A displacer for an engine includes a body extending along a displacer longitudinal axis from a displacer first end surface to a displacer second end surface. At least one channel extends between a first opening in the displacer first end surface and a second opening in the displacer second end surface and has sidewalls therebetween defining a channel flow path. The first opening is located at a first radial distance from the displacer longitudinal axis in a first radial direction and the second opening is located at a second radial distance from the displacer longitudinal axis in a second radial direction. At least a portion of the channel flow path has a component in an angular direction that is at an angle to both the first and second radial directions.