Looking for breakthrough ideas for innovation challenges? Try Patsnap Eureka!

Method for eliminating thermal buckling of lattice sandwich panel structure and restraining nonlinear flutter

A sandwich panel and nonlinear technology, which is applied in the field of eliminating thermal buckling of lattice sandwich panel structures and suppressing nonlinear flutter, can solve the problems of structural natural frequency changes, active stiffness cannot fully compensate for temperature changes, etc., and achieve design saving The effect of installation time

Inactive Publication Date: 2020-09-29
HARBIN ENG UNIV
View PDF2 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The purpose of the present invention is to solve the problem that existing piezoelectric materials are often used in the control of structural flutter and thermal buckling, and the active stiffness cannot fully compensate for the influence of temperature changes, and will also cause changes in the natural frequency of the structure. Now a kind of Method of Eliminating Thermal Buckling and Suppressing Nonlinear Flutter of Lattice Sandwich Panel Structure

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for eliminating thermal buckling of lattice sandwich panel structure and restraining nonlinear flutter
  • Method for eliminating thermal buckling of lattice sandwich panel structure and restraining nonlinear flutter
  • Method for eliminating thermal buckling of lattice sandwich panel structure and restraining nonlinear flutter

Examples

Experimental program
Comparison scheme
Effect test

specific Embodiment approach 1

[0022] Embodiment 1: A method for eliminating thermal buckling of a lattice sandwich panel structure and suppressing nonlinear flutter described in this embodiment includes the following steps:

[0023] Step 1: Establish the strain-displacement relationship and constitutive relationship of the lattice sandwich panel structure based on the geometric deformation of the lattice sandwich panel structure;

[0024] Step 2: Establish the expressions of the supersonic aerodynamic force and the work done by the in-plane thermal load and the mathematical model of the elastic foundation structure, obtain the expressions of the kinetic energy, deformation energy and elastic foundation potential energy of the lattice sandwich panel, and establish points based on the Hamilton variational principle The aerodynamic thermoelastic motion equation of the array sandwich panel structure;

[0025] Step 3: Solve the aerothermoelastic motion equation of the lattice sandwich panel structure based on t...

specific Embodiment approach 2

[0026] Specific implementation mode two: the detailed steps of described step one are:

[0027] Step ①: Establish the expression of the displacement field of the lattice sandwich panel structure:

[0028] w (p) =w,p=1,2;

[0029] u (3) =u-zθ x , v (3) =v-zθ y ,w (3) = w;

[0030] The superscript "p" represents the upper panel and the lower panel of the lattice sandwich panel structure, 1 is the upper panel of the lattice sandwich panel structure, and 2 is the lower panel of the lattice sandwich panel structure; the superscript "3" represents the lattice sandwich panel core plate structure core; h c is the thickness of the core; u, v and w are the displacements of the structural neutral plane along the x, y and z axes respectively; θ x and θ y represent the rotation angles of the neutral plane along the y and x axes, respectively;

[0031] Step ②: Establish the expression of the strain-displacement relationship of the lattice sandwich panel structure through the ex...

specific Embodiment approach 3

[0046] Specific implementation mode three: the core equivalent shear modulus G in the step 3. c The expression is:

[0047]

[0048] Among them, ρ r is the relative density of the core, Ec is the elastic modulus of the pyramid core material, α c is the inclination angle of the pyramid lattice rod;

[0049] where ρ r The expression is:

[0050]

[0051] where l c is the length of the pyramid lattice rod; α c is the inclination angle of the pyramid lattice rod; r c is the radius of the pyramid lattice rod.

[0052] Other steps and parameters are the same as those in Embodiment 1 or Embodiment 2.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention discloses a method for eliminating thermal buckling of a lattice sandwich panel structure and restraining nonlinear flutter. The invention aims to solve the problems that an existing piezoelectric material is often used for controlling flutter and thermal buckling of a structure, the influence caused by temperature change cannot be completely compensated by active rigidity, and the change of the inherent frequency of the structure is also caused. The method comprises the following steps: establishing a strain-displacement relationship and a constitutive relationship of a latticesandwich panel structure; establishing expressions of work done by supersonic aerodynamic force and in-plane thermal load and a mathematical model of the elastic foundation structure, obtaining expressions of kinetic energy, deformation energy and elastic foundation potential energy of the dot matrix sandwich panel, and establishing an aerodynamic thermal elastic motion equation of the dot matrixsandwich panel structure; based on a four-order Runge-Kutta method, solving an aerodynamic thermoelastic motion equation of the lattice sandwich panel structure, and performing analyzing to obtain aninfluence rule of an elastic foundation on aerodynamic thermoelastic characteristics of the lattice sandwich panel structure. The invention belongs to the field of aerospace.

Description

technical field [0001] The invention relates to a method for eliminating thermal buckling of a lattice sandwich panel structure and suppressing nonlinear flutter. Background technique [0002] The lattice sandwich structure is a new type of laminated material structure, which has excellent characteristics such as light weight, high specific strength, high specific stiffness, noise reduction and heat insulation, and is extremely suitable for the design of future aircraft structures. Since aircraft structures are often placed on elastic media such as thermal protection layers or damping strips, elastic media have a great influence on the aerothermoelastic properties of lattice sandwich structures. Therefore, it is of great significance to study the aerothermoelasticity of elastic basic lattice sandwich structures in supersonic airflow. In addition, in order to further improve the reliability of future hypersonic vehicles, so that they can fly stably and safely in complex envi...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
IPC IPC(8): G06F30/15G06F30/20G16C60/00G06F111/10G06F113/26G06F119/08
CPCG06F30/15G06F30/20G16C60/00G06F2113/26G06F2119/08G06F2111/10Y02T90/00
Inventor 柴玉阳李凤明宋智广
Owner HARBIN ENG UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Patsnap Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com