A Two-parameter Robust Design Method for Special-Shaped Bolt Holes Based on Minimal Profile Variation

Abstract

The invention discloses a robust two-parameter irregular bolt hole design method based on minimum outline change. In optimization design, the method adopts optimization objectives of (a) decreasing of a hole side stress to reach a task specified value, (b) controlling irregular hole outline change amplitude (namely avoiding too large difference between an irregular bolt outline and an original round outline) and the like. In an optimization model, a comprehensive irregular hole optimization design model is established by conducting reasonable weighting summation processing on each optimization objective. In addition, an irregular hole balance optimization design effect under the multi-objective condition is obtained by adopting a method for dynamically adjusting weighting coefficients balanced in contribution to the comprehensive optimization objectives based on different design objectives, the dependency on a design variable value range of irregular hole design variable (namely circular arc size) optimization results is fundamentally eliminated, and the best irregular hole outline meeting the strength design task requirement conditions and having minimum outline change can be obtained through rapid optimization. Design results have better consistency.

Description

technical field [0001] The invention belongs to the structural optimization design of turbine rotor components of aero-engines, and in particular relates to a multi-objective optimization design model of the profile shape of biaxially symmetrical special-shaped bolt holes of a turbine disk. Background technique [0002] The long-term working environment of the high-pressure turbine disc of the aero-engine is harsh, and the round bolt hole on the front mounting edge often has cracks at the edge of the hole due to stress concentration, which has become an important reason for the failure of the disc. [0003] The patent "multi-arc special-shaped hole" (patent number: ZL2013 1 0287309.9) proposes an eight-arc special-shaped hole structure. But still there are following deficiencies: [0004] 1. There is an over-optimization phenomenon in the optimal value of the objective function in the existing optimization model (that is, the stress drop at the edge of the hole exceeds the ...

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Problems solved by technology

[0004] 1. There is an over-optimization phenomenon in the optimal value of the objective function in the existing optimization model (that is, the stress drop at the edge of the hole exceeds the design requirement)

[0005] 2. The optimal design results are too dependent on the setting of the value range of the design variables. In the actual design, continuous trial calculations are required to determine the reasonable value range of the design variables, and the design efficiency is low.

[0006] 3. The robustness of the optimization design results is poor, and the convergence speed of the optimization process is slow

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