Method and system for metallic low pressure fan case heating
AssigneeGeneral Electric Company
InventorsHemanth Gudibande Sathyakumar Kumar, Bhaskar Nanda Mondal, Thomas Ory Moniz
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Abstract
A fan assembly is provided. The fan assembly includes a fan, a fan casing circumscribing the fan, and a fan casing heating system in thermal communication with the fan casing. The fan includes a hub, and a plurality of fan blades extending from the hub. Each fan blade of the plurality of fan blades terminates at a respective blade tip. A clearance gap is defined between the fan casing and the blade tips. The fan casing heating system is configured to apply heat to the fan casing when the fan is operating in a first operational mode, and remove the applied heat when the fan transitions into a second operational mode.
Claims26
A fan assembly comprising:
- a fan comprising:
- a hub;
- and
- a plurality of fan blades extending from said hub, each fan blade of said plurality of fan blades terminating at a respective blade tip;
- a fan casing circumscribing said fan, wherein a clearance gap is defined between said fan casing and said blade tips;
- and
- a fan casing heating system in thermal communication with said fan casing, said fan casing heating system configured to:
- apply heat to said fan casing when said fan is operating in a first operational mode;
- and
- remove the applied heat when said fan transitions into a second operational mode.
A turbofan engine comprising:
- a core engine including a multistage compressor;
- a fan powered by a low-pressure turbine driven by gas generated in said core engine, said fan comprising:
- a hub;
- and
- a plurality of fan blades extending from said hub, each fan blade of said plurality of fan blades terminating at a respective blade tip;
- a fan casing circumscribing said fan, wherein a clearance gap is defined between said fan casing and said blade tips;
- a fan casing heating system in thermal communication with said fan casing;
- and
- a processor programmed to:
- apply, using said fan casing heating system, heat to said fan casing radially outboard and axially aligned with said fan when said fan is operating in a first operational mode such that said fan casing expands by a predetermined amount, increasing the clearance gap to a first distance;
- and
- remove, using said fan casing heating system, the applied heat to contract said fan casing when said fan transitions into a second operational mode, decreasing the clearance gap to a second distance, wherein the second distance is less than the first distance.
A method of controlling a clearance gap between respective tips of a plurality of blades of a fan and a fan casing, said method comprising:
- applying heat to the fan casing radially outboard and axially aligned with the fan such that the fan casing expands by a predetermined amount, increasing the clearance gap to a first distance;
- operating the fan in a first operational mode;
- transitioning the fan to a second operational mode;
- removing the applied heat to contract the fan casing, decreasing the clearance gap to a second distance, wherein the second distance is less than the first distance;
- and
- operating the fan with the clearance gap at the second distance.
A method of controlling a clearance gap between respective tips of a plurality of radially extending blades of a rotatable body and a cylindrical casing circumscribing the rotatable body, said method comprising:
- applying heat to the casing radially outboard and axially aligned with the rotatable body such that the casing expands by a predetermined amount, increasing the clearance gap to a first distance;
- operating the rotatable body in a first operational mode;
- transitioning the rotatable body to a second operational mode;
- removing the applied heat to contract the casing, decreasing the clearance gap to a second distance, wherein the second distance is less than the first distance;
- and
- operating the rotatable body with the clearance gap at the second distance.
Dependencies are inferred from the claim text.