An unsteady aerodynamic force order reduction method based on generalized aerodynamic force

A kind of unsteady aerodynamic and aerodynamic technology, applied in the direction of instruments, complex mathematical operations, calculations, etc., can solve the problems of limited use, time-consuming, large amount of calculation, etc., to achieve the effect of improving accuracy, reducing difficulty, and reducing order.

Active Publication Date: 2019-06-25
NORTHWESTERN POLYTECHNICAL UNIV
View PDF5 Cites 13 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this method is computationally intensive and time-...

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
  • An unsteady aerodynamic force order reduction method based on generalized aerodynamic force
  • An unsteady aerodynamic force order reduction method based on generalized aerodynamic force
  • An unsteady aerodynamic force order reduction method based on generalized aerodynamic force

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0048] Embodiments of the present invention are described in detail below, and the embodiments are exemplary and intended to explain the present invention, but should not be construed as limiting the present invention.

[0049] The invention relates to an aerodynamic order reduction method based on generalized aerodynamic force, which includes: coordinate transformation, interpolation aerodynamic order reduction and aerodynamic time domain fitting. First, through coordinate transformation, the generalized aerodynamic force under the modal coordinates is transformed into the unsteady aerodynamic force distributed on the nodes of the finite element model under the physical coordinates, and then the distributed unsteady aerodynamic force is reduced by surface spline interpolation, which is equivalent to A reduced-order aerodynamic model in the frequency domain is obtained at a limited number of loading points, and finally the reduced-order aerodynamic model in the frequency domain...

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 provides an unsteady aerodynamic force order reduction method based on generalized aerodynamic force. The method comprises steps of firstly, converting generalized aerodynamic force under modal coordinates into unsteady aerodynamic force distributed on all nodes of a structural finite element model under physical coordinates through coordinate transformation; secondly, performing order reduction on the distributed unsteady aerodynamic force through curved surface spline interpolation, equivalently concentrating the unsteady aerodynamic force to a limited loading point so as to obtain a frequency domain aerodynamic force order reduction model, and finally fitting the frequency domain order reduction aerodynamic force model to a time domain by using a minimum state method. According to the method, the precision of the reduced-order aerodynamic model is improved on the basis of reducing the order of the reduced-order aerodynamic model as much as possible, so that the difficulty of designing an excitation force control system in a ground flutter simulation test is reduced, and the reduced-order method can be used for transonic flutter analysis by means of a CFD transonicvelocity unsteady aerodynamic calculation method.

Description

technical field [0001] The design of the invention belongs to the technical field of aircraft aeroelasticity test, and is specifically an unsteady aerodynamic order reduction method based on generalized aerodynamic force. Background technique [0002] Flutter is a kind of self-excited vibration with non-attenuating amplitude under the coupled action of aerodynamic force, elastic force and inertial force. At present, the main ways to study the flutter problem of aircraft structure are theoretical calculation and flutter test. [0003] Although theoretical calculation saves time and money, when establishing a mathematical model of the analysis object, some assumptions need to be introduced in terms of structure and aerodynamics, which may have a large deviation from the real situation. [0004] The flutter test is divided into wind tunnel flutter test and flight flutter test: the wind tunnel flutter test directly considers the effect of aerodynamic force, but the test model n...

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): G06F17/50G06F17/16
CPCY02T90/00
Inventor 张桂玮杨智春宋巧治谷迎松陈宇
Owner NORTHWESTERN POLYTECHNICAL UNIV
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products