CN-122020838-A - Dynamic optimization method and device for periodic impact load supporting structure

CN122020838ACN 122020838 ACN122020838 ACN 122020838ACN-122020838-A

Abstract

The invention provides a dynamic optimization method of a periodic impact load supporting structure, which comprises the steps of obtaining the excitation frequency of periodic impact load applied to the supporting structure Obtaining the initial first-order natural frequency of the supporting structure by finite element analysis or directly adopting a mode test Determining whether there is a k not less than k 0 such that If so, the initial first-order natural frequency is obtained As the natural frequency of the support structure. Can be used for guiding and referencing related structural design.

Inventors

CHEN YINGHUA
MA XIAOYAN
ZHANG GUIBAO

Assignees

中国直升机设计研究所

Dates

Publication Date: 20260512
Application Date: 20251224

Claims (8)

1. A method of dynamic optimization of a cyclic impact load support structure, the method comprising: acquisition of the excitation frequency of a periodic impact load to which the support structure is subjected ; Obtaining the initial first-order natural frequency of the supporting structure by finite element analysis or directly adopting a mode test ; Determining whether there is a k not less than k 0 such that ; If present, the initial first order natural frequency As the natural frequency of the support structure.
2. The method of claim 1, wherein the initial first order natural frequency is determined Before being the natural frequency of the support structure, the method further comprises: Judging initial first-order natural frequency Whether or not to be equal to ; If not, according to Optimizing initial first order natural frequency 。
3. The method of claim 1, wherein k 0 has a value of 3.
4. The method according to claim 1, wherein the method further comprises: If there is no k not less than k 0 , then When according to Optimizing initial first order natural frequency ; At the position of When according to Or (b) Optimizing initial first order natural frequency 。
5. The method of claim 1, wherein the excitation frequency of the periodic impact load ; N is the frequency of application of the periodic impact load to the support structure in times per minute.
6. A dynamic optimization device for a cyclic impact load support structure, comprising: An excitation frequency acquisition module for acquiring the excitation frequency of the periodic impact load applied to the support structure ; The natural frequency acquisition module is used for acquiring the initial first-order natural frequency of the support structure through finite element analysis or directly adopting a mode test ; A detection module for judging whether k not less than k 0 exists so as to ; An optimizing module for optimizing the initial first-order natural frequency when present As the natural frequency of the support structure.
7. The apparatus of claim 6 wherein the optimization module is further configured to determine an initial first order natural frequency Whether or not to be equal to ; If not, according to Optimizing initial first order natural frequency 。
8. The apparatus of claim 6, wherein k 0 has a value of 3.

Description

Dynamic optimization method and device for periodic impact load supporting structure Technical Field The invention belongs to the technical field of helicopter structure dynamics design, and particularly relates to a dynamics optimization method and device for a periodic impact load supporting structure. Background In the use process of the aviation structure, the action frequency of periodic impact load and the dynamics matching degree of the installation structure relate to the size of structural response, and poor dynamics matching often causes superposition amplification of structural dynamic response and even resonance, so that the transmission of load is increased, unnecessary structural weight gain is brought, and the design difficulty of equipment with precision requirements is increased. Therefore, the dynamic matching design of the structure subjected to the periodic impact load is a necessary means for reducing the structural load and the weight and improving the index of precision equipment. In the current model design, the aviation structure design is more concerned about the strength problem caused by load peaks, and the lack of relevant specifications and requirements for the dynamic matching of periodic impact loads, in particular to a structural rigidity design method, has become a key factor for restricting the development and application of the aircraft. Disclosure of Invention The invention aims to provide a dynamic optimization method and device for a periodic impact load supporting structure, which comprise the aspects of frequency analysis, oscillation period calculation, frequency matching, fixed frequency design and the like. A first aspect of the invention provides a method of dynamic optimisation of a cyclic impact load support structure, the method comprising: acquisition of the excitation frequency of a periodic impact load to which the support structure is subjected ; Obtaining the initial first-order natural frequency of the supporting structure by finite element analysis or directly adopting a mode test; Determining whether there is a k not less than k 0 such that; If present, the initial first order natural frequencyAs the natural frequency of the support structure. Optionally, at the initial first order natural frequencyBefore being the natural frequency of the support structure, the method further comprises: Judging initial first-order natural frequency Whether or not to be equal to; If not, according toOptimizing initial first order natural frequency。 Alternatively, k 0 has a value of 3. Optionally, the method further comprises: If there is no k not less than k 0, then When according toOptimizing initial first order natural frequency; At the position ofWhen according toOr (b)Optimizing initial first order natural frequency。 Alternatively, the excitation frequency of the periodic impact load; N is the frequency of application of the periodic impact load to the support structure in times per minute. A second aspect of the invention provides a dynamic optimisation apparatus for a cyclic impact load support structure comprising: An excitation frequency acquisition module for acquiring the excitation frequency of the periodic impact load applied to the support structure ; The natural frequency acquisition module is used for acquiring the initial first-order natural frequency of the support structure through finite element analysis or directly adopting a mode test; A detection module for judging whether k not less than k 0 exists so as to; An optimizing module for optimizing the initial first-order natural frequency when presentAs the natural frequency of the support structure. Optionally, the optimization module is further configured to determine an initial first-order natural frequencyWhether or not to be equal to; If not, according toOptimizing initial first order natural frequency。 Alternatively, k 0 has a value of 3. The invention has the beneficial effects that: The invention provides a dynamic optimization method and a dynamic optimization device for a periodic impact load supporting structure, provides a dynamic design method based on periodic impact load excitation frequency and dynamic characteristic matching of the supporting structure, and can be used for guiding and referencing related structural design. Aiming at the defect of the current aviation structure dynamics design method under the periodic impulse excitation environment, the provided structure dynamics design method can give out the dynamics requirement of the support structure design according to the working frequency of the periodic impulse excitation, and can effectively prevent or eliminate the response superposition problem caused by the periodic impulse excitation. Drawings In order to more clearly illustrate the embodiments of the invention or the technical solutions in the prior art, the drawings that are required in the description of the embodiments or the prior art will be briefly described, in