Labyrinth seal comprising an abradable element with variable cell density

A method for manufacturing a labyrinth seal for a turbomachine,

• the labyrinth seal including a rotor element and a stator element extending around the rotor element,
• the rotor element being configured to rotate relative to the stator element about an axis of rotation along an axial direction,
• the stator element carrying an abradable element,
• the rotor element including an annular wiper having an outer radial end extending towards the abradable element,
• the outer radial end of the annular wiper having a corrugation along the axial direction, the corrugation having a non-zero axial extent, the outer radial end of the annular wiper having a constant axial extent at any position of the outer radial end of the annular wiper along a circumferential direction;
• the abradable element including cells disposed adjacent to each other along the axial direction and along the circumferential direction, the cells comprising walls which extend in a substantially radial direction,
• the method comprising:
• manufacturing the annular wiper;
• and
• manufacturing the abradable element including a first densified annular area located directly facing the outer radial end of the wiper along the axial direction, the first densified annular area having a first cell density, the first densified annular area having an axial extent less than or equal to the axial extent of the corrugation,
• all cells of the abradable element located outside the first densified annular area and immediately adjacent to the first densified annular area being distributed according to a reference cell density, the first cell density being superior to the reference cell density.

A method for manufacturing a labyrinth seal for a turbomachine,

• the labyrinth seal including a rotor element and a stator element extending around the rotor element,
• the rotor element being configured to rotate relative to the stator element about an axis of rotation along an axial direction,
• the stator element carrying an abradable element,
• the rotor element including an annular wiper having an outer radial end extending towards the abradable element,
• the outer radial end of the annular wiper having a corrugation along the axial direction, the corrugation having a non-zero axial extent,
• the abradable element including cells disposed adjacent to each other along the axial direction and along an orthoradial direction, the cells comprising walls which extend in a substantially radial direction,
• the method comprising:
• manufacturing the annular wiper;
• and
• manufacturing the abradable element including a first densified annular area located directly facing the outer radial end of the wiper, the first densified annular area having a first cell density, the first densified annular area having an axial extent less than or equal to the axial extent of the corrugation, the cells being distributed according to a reference cell density outside the first densified annular area, the first cell density being superior to the reference cell density,
• measuring the axial extent of the corrugation,
• determining a least one of the axial extent of the first densified annular area, an axial extent of a second densified annular area and an axial extent of a third densified annular area of between 40% and 100% of the measurement of the axial extent of the corrugation.