A shell structure for a turbine engine that includes a plurality of diaphragms, wherein each diaphragm comprises: an annularly formed support structure that positions and secures a row of circumferentially spaced stator blades, and wherein the plurality of diaphragms are configured and axially stacked such that each diaphragm abuts the diaphragm that is positioned directly upstream from it and the diaphragm that is positioned directly downstream from it such that a first shell structure is formed; a second shell structure disposed outboard of the first shell structure; and an intermediate chamber defined between an outboard face of the first shell structure and an inboard face of the second shell structure; wherein: a downstream end and an upstream end of the first shell structure define the axial length of the first shell structure; one or more downstream radial ports are defined at the approximate axial position of the downstream end of the first shell structure, each downstream radial port fluidly connecting the intermediate chamber to the main flow path of the turbine engine; and between the axial position of the downstream axial ports and the axial position of the upstream end of the first shell structure, the first shell structure is configured such that the intermediate chamber is substantially sealed from the main flow path.