Modeling method of liquid sloshing in microgravity environment of spherical tank

A liquid sloshing and microgravity technology, applied in simulators, instruments, control/regulation systems, etc., can solve the problems of complex sloshing of propellant in the tank, difficulty in meeting engineering needs, and low solution efficiency

Active Publication Date: 2017-07-14
BEIJING INST OF SPACECRAFT SYST ENG
View PDF2 Cites 11 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The spacecraft has a high positioning accuracy. During the attitude maneuvering and stabilization process, the spacecraft tank is faced with a microgravity environment, and the surface tension of the propellant in the tank begins to appear, which may lead to complex sloshing of the propellant in the tank. characteristics, which have an impact on the high-precision attitude control of the platform
The existing small linear shaking modeling methods can no longer meet the needs

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
  • Modeling method of liquid sloshing in microgravity environment of spherical tank
  • Modeling method of liquid sloshing in microgravity environment of spherical tank
  • Modeling method of liquid sloshing in microgravity environment of spherical tank

Examples

Experimental program
Comparison scheme
Effect test

Embodiment

[0170] The radius of the spherical storage tank is R=0.547m, the liquid filling ratio is 25%, and the liquid is water at normal temperature. Obtain its equivalent spring-mass model by calculation, m s =102.8kg, m 0 =68.48kg, K s =0.14425N / m, C s = 0.2827 Ns / m.

[0171] The coordinates of the sphere center of the tank in the body coordinate system are (0.3,0.4,0.5)m, and the translation excitation along the x-axis direction and the rotation excitation around the x-axis direction are applied to the tank, and the motion laws are x=0.01sin (0.1πt)m and θ x =0.01sin(0.2πt)rad. The acceleration of gravity is along the negative direction of the z axis, and the magnitude is g=10 -5 m / s 2 . Obtain the force of the liquid on the tank as Figure 4 and as shown in 5. Figure 4 and Figure 5 The response of the same tank calculated under the same excitation conditions using the commercial software Flow-3d is also plotted. The comparison results show that the error is less than ...

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 a modeling method of liquid sloshing in a microgravity environment of a spherical tank. Firstly, an equivalent mechanical model of liquid sloshing under the microgravity environment of a spherical tank is established. The equivalent mechanical model is a three-axis spring-mass equivalent mechanical model which contains the rest mass m0 and the sloshing mass ms, wherein the rest mass m0 is located in the center of the spherical tank, the sloshing mass is connected with the tank by three spring dampers with a stiffness coefficient of Ks and a damping coefficient of Cs. When the sloshing mass is in the equilibrium position, the directions of the three spring dampers are respectively overlapped with the three axes of the spherical tank. Then, the n-order natural frequency [omega]0i and the modal [phi]i of the liquid sloshing in the zero-gravity environment of the spherical tank are calculated. Finally, based on the force of the liquid applied to the wall of the tank and the kinetic energy of the sloshing liquid relative to the tank, the force of the equivalent mechanical model and the kinetic energy equivalent principle, the sloshing mass ms and the rest mass m0 of the equivalent mechanical model are obtained by calculation.

Description

technical field [0001] The invention is applied in the field of liquid sloshing analysis of liquid-filled spacecraft, and specifically relates to a modeling method for liquid sloshing in a spherical storage tank in a microgravity environment. Background technique [0002] According to the overload conditions of the spacecraft during flight, the movement of the fluid in the storage tank can be divided into several working conditions: weightlessness, micro-gravity, low-weight, normal weight and overweight. and slow rotation conditions, etc. For liquid-filled spacecraft, the main research is on the fluid motion characteristics of weightlessness or microgravity and low-gravity and spin conditions. Theory and practice show that when the Bond number ( Where ρ is the density of the liquid; g is the overload acceleration; L 0 is the characteristic length, generally taken as the radius of the free liquid surface; when σ is the surface tension coefficient) is 0, it can be regarded...

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): G05B17/02
CPCG05B17/02
Inventor 柳翠翠王天舒关晓东王黎珍于登云
Owner BEIJING INST OF SPACECRAFT SYST ENG
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