Simplification and equivalence method for dense exhaust film holes for nickel-based single crystal turbine blades

Abstract

The invention discloses a simplification and equivalence method for dense exhaust film holes of nickel-based single crystal turbine blades, belonging to the technical field of structural reliability analysis and optimization design. The method for solving the structural failure probability determines a blade plate model according to the arrangement mode of the dense exhaust film holes of the blade, and simplifies the blade plate model into an equivalent single-hole model; dividing the equivalent single hole model into a plane stress state region and a generalized plane strain state region according to the thickness difference of the equivalent single hole model; according to the stress-strain relationship of the blade plate model and the equivalent single-hole model, the expressions of theequivalent elastic constants of the equivalent single-hole model under the plane stress state and the generalized plane strain state are derived. The simplified and equivalent method can calculate the stress and strain fields around the film cooling holes and determine the life of the turbine blades at the same time.

Description

technical field [0001] The invention belongs to the technical field of structural reliability analysis and optimal design, and in particular relates to a simplified and equivalent method for a nickel-based single crystal turbine blade airtight membrane hole. Background technique [0002] At present, nickel-based single crystal superalloys are widely used as turbine blade materials in the world. This alloy not only has excellent thermal corrosion resistance and oxidation resistance, but also has outstanding high temperature creep, fatigue performance and structural stability, and is widely used in Manufacture of hot end parts of aviation and aerospace engines. In order to adapt to the higher and higher turbine inlet temperature, the turbine blades of aero-engines mostly adopt the structure with airtight exhaust film cooling holes on the blade body. The stress-strain field at the edge of the film cooling hole is extremely complex, and accurate calculation of the stress and st...

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Problems solved by technology

In the finite element simulation calculation of turbine blades, the existence of a large number of air film holes will lead to a huge amount of calculation

[0003] At present, the equivalence of air film holes for blade cooling is mainly used in isotropic materials, such as the equivalence of material properties of structures with holes. The simplification and equivalent methods are based on isotropic materials, and the The same amount of deformation is the equivalent judgment standard, and the nickel-based single crystal alloy mainly used in domestic aero-engines is an anisotropic material, and its mechanical properties are orientation-dependent and sensitive, and the existing equivalent simplified method cannot be applied

Moreover, the airtight membrane holes are arranged in different ways, and a single simplified model cannot satisfy all situations.

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