PURPOSE: To flex a liner with high pressure exhaust gas to prevent icing and ensure smooth exhaust of gas by forming a tubular liner with an outside surface of a diameter smaller than the inner diameter of an exhaust passage and a smooth inside surface, and arranging a plurality of projecting spacers on the outside surface for the purpose of arranging the liner in the passage in a state that the outside surface is spaced from the inside surface of the passage.

CONSTITUTION: A liner 22 is arranged in a passage 18. The liner 22 has a first end 24 and a second end 26, and an inside surface and an outside surface 30. A plurality of projecting spacers 32 are arranged on the outside surface 30. The spacers 32 are set to contact the inside surface of the passage 18. Thus, when pressurized air is applied to the liner 22, the liner 22 is suitably flexed to crash the ice or allow the ice to fall from the smooth inside surface 28 of the liner 22. The liner 22 has a flange 36 at the first end 24. The flange 36 forms a seal against an end of the passage 18. A flange 38 of the second end 26 also forms a seal against the passage 18.