Unlock instant, AI-driven research and patent intelligence for your innovation.

Magneto-rheological shock absorber fatigue testing method and system

A magneto-rheological shock absorber and fatigue testing technology, which is applied in the field of fatigue testing, can solve problems such as component damage, insufficient inspection of magnetorheological shock absorber life, fatigue, etc.

Active Publication Date: 2019-10-08
TSINGHUA UNIV +1
View PDF6 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0003] Fatigue life is an index that must be investigated in the practical application of magneto-rheological shock absorbers. In addition to considering from the perspective of ordinary shock absorbers, there are also unique aspects that need to be considered: 1. The damping force of the magnetorheological shock absorber is adjusted by loading different currents. There is no basis for how much current is loaded in the fatigue test.
If no current is applied, it obviously does not meet the functional requirements of the magneto-rheological shock absorber, and it is not enough to examine the life of the magnetorheological shock absorber; The reliability test requirements are too high, and fatigue problems may occur if the required number of tests may not be met
The second is that the magnetorheological fluid is constantly squeezed and rubbed in the damping channel, and the base carrier fluid and suspended soft magnetic particles will cause oxidation fatigue. Therefore, the service life of the magnetorheological fluid itself needs to be investigated
[0004] At present, there is a lack of effective methods to guide the fatigue test of magneto-rheological shock absorbers

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
  • Magneto-rheological shock absorber fatigue testing method and system
  • Magneto-rheological shock absorber fatigue testing method and system
  • Magneto-rheological shock absorber fatigue testing method and system

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0071] figure 1 It is a flowchart of a fatigue test method for a magneto-rheological shock absorber in Embodiment 1 of the present invention.

[0072] see figure 1 , the magneto-rheological shock absorber fatigue test method of the embodiment, comprising:

[0073] Step S1: Determine the periodic vibration excitation value required to load the magneto-rheological damper.

[0074] The periodic vibration excitation value includes vibration amplitude and vibration frequency.

[0075] Step S2: Determine the range interval of cumulative dissipated energy per unit volume.

[0076] The range of accumulated energy dissipation per unit volume is 1.0×10 6 J / cm 3 ≤W LDE ≤1.0×10 7 J / cm 3 ;W LDE Indicates the cumulative dissipated energy value per unit volume.

[0077] Step S3: Determine the current loading range interval.

[0078] The current value within the range of current loading is not greater than the maximum continuous current that the copper wire used for the magneto-rhe...

Embodiment 2

[0099] The fatigue life of magnetorheological fluid has a strong correlation with the energy dissipated per unit volume. figure 2 It is a graph showing the relationship between the viscosity of the four magnetorheological fluids in Example 2 of the present invention and the cumulative dissipated energy per unit volume. Depend on figure 2 It can be seen that the accumulative energy dissipated per unit volume of bad magnetorheological fluid only reaches 10 5 J / cm 3 When it is even lower, oxidative fatigue will occur, and the zero-field viscosity will increase significantly, and it will even appear in the form of cement at zero-field, which cannot be used any longer. And the magnetorheological fluid with good durability can dissipate 10% of the accumulated energy per unit volume. 7 J / cm 3 Still works fine.

[0100] Therefore, the accumulated energy dissipated per unit volume of the magneto-rheological fluid in the magneto-rheological shock absorber is defined as:

[0101]...

example 1

[0128] Example 1: Take the magneto-rheological shock absorber 1 of the vehicle suspension as an example, the body temperature of the shock absorber is 70°C, the load current is 1.0A, and the dynamometer diagram under the sinusoidal excitation with a displacement amplitude of ±50mm and a frequency of 1.67Hz is as follows image 3 shown.

[0129] Calculate the area of ​​the dynamometer diagram by using the existing calculation method for the area of ​​the dynamometer diagram That is, the heat dissipated in one cycle of shock absorber movement is P=270J. Take W LED =2.0×10 6 J / cm 3 , V mrf =250cm 3 , the expected number of test cycles n∈[1.0×10 6 ,2.0×10 6 ], calculated to get: n=1.8519×10 6 , the total time consumption: time=n / f / 3600=308.039h. n is within the required range, therefore, the magneto-rheological shock absorber is loaded with a current of 1.0A, W LED =2.0×10 6 J / cm 3 applied in practice.

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 magneto-rheological shock absorber fatigue testing method and system. The method comprises the following steps: selecting any current value in the current range interval as the current testing current value, selecting any unit volume accumulative dissipation energy value in the current dissipation energy range interval as the current unit volume accumulative dissipation energy testing value; at the preset temperature, obtaining an indicator diagram of the magneto-rheological shock absorber according to the current testing current value and the periodic vibration excitation value; determining the single-period dissipation heat according to the indicator diagram; computing the testing period number according to the single-period dissipation heat and the current unitvolume accumulative dissipation energy testing value; judging whether the testing period number is in the preset period range; if the testing period number is located in the preset period range, ending the testing; if the testing period number is not located in the preset period range, re-adjusting the current testing current value and the current unit volume accumulative dissipation energy testing value. The fatigue test of the magneto-rheological shock absorber can be guided, so that the magneto-rheological shock absorber can be well applied in the practice.

Description

technical field [0001] The invention relates to the technical field of fatigue testing, in particular to a fatigue testing method and system for a magneto-rheological shock absorber. Background technique [0002] Magnetorheological fluid is a kind of smart material sensitive to magnetic field. It has good fluidity when there is no external magnetic field; shear yield strength. The shear yield strength of magnetorheological fluid increases with the increase of the external magnetic field, so a greater shear stress is required to make it yield and flow. Dampers, valves and other devices are made of this characteristic of magnetorheological fluid, and the viscosity of magnetorheological fluid is controlled by a magnetic field, so as to realize the damping adjustment of these devices. Because magnetorheological dampers and magnetorheological valves have the advantages of fast response, good controllability, simple structure, and low energy consumption, they have good applicati...

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): G01M13/00
CPCG01M13/00
Inventor 危银涛彭志召张进秋
Owner TSINGHUA UNIV