Thermal insulating layer for hot channel of hypersonic-velocity wind tunnel

The invention relates to a thermal insulating layer, and in particular relates to a thermal insulating layer for a hot channel of a hypersonic-velocity wind tunnel. The thermal insulating layer is in a cylindrical structure and comprises a cylinder body and two cylinder covers, wherein the cylinder body is formed by rolling a plurality of metal plates; each cylinder cover is manufactured by a metal plate; the two cylinder covers are respectively welded at the two ends of the cylinder body; and each metal plate is of a convex structure. The thermal insulating layer adopts a structure with the multiple metal plates, utilizes air among the thin plates for thermal insulation and fulfills the purposes of resisting the brush of air flow and the pressure of the internal air flow by utilizing the strength of the metal plates, so that a pressure balance hole does not need to be formed, the service life of the thermal insulation layer structure is prolonged, and the pollution of thermal insulating materials to a flow f