CN103983438B - Method for testing service life of turning control system of airplane - Google Patents

Abstract

The invention belongs to the field of undercarriage fatigue life tests and relates to a method for testing the service life of a turning control system of an airplane. The method is characterized in that firstly, the damage ratio of platform take-off and landing to land-based take-off and landing is determined; secondly, the ratio of platform take-off and landing to land-based take-off and landing is determined; thirdly, the frequency of land-based take-off and landing and the frequency of platform take-off and landing are calculated; fourthly, the frequency of turning in the process of land-based take-off and landing and the frequency of turning in the process of platform take-off and landing are counted; fifthly, the reliability coefficient of a test is calculated; sixth, the cycle number of the test is calculated. The method has the advantages that the use conditions of land-based take-off and landing and platform take-off and landing are considered, the design of the test better accords with real use conditions, and a test result is more accurate.

Description

A kind of aircraft turn steerable system life test method

Technical field

The invention belongs to undercarriage fatigue life test field, it is related to multi-platform use undercarriage turn control system Life test method.

Background technology

Aircraft is different in continental rise from the service condition of platform.Platform landing damages substantially tight to the undercarriage of aircraft Weight, substantially reduces the life-span of undercarriage.Meanwhile, in order to meet the requirement of platform use, undercarriage turn control system is also compared with land Base aircraft has differences, and is provided that bigger angle of turn.How to determine turn control system according to multi-platform service condition Service life become a major issue in undercarriage Intensity Design.

The analysis of land airplane undercarriage turn control system lifetim and experimental technique are comparative maturities, but can not solve Two key issues that certainly undercarriage steerable system platform uses:

1) gear steering system index of aging will be matched with the index of aging of undercarriage, and reflects the flat of undercarriage Platform, continental rise service condition.

2) the gear steering system life-span will embody the particularity of platform use, reflects to wide-angle turning situation pair The impact in undercarriage life-span.

Content of the invention

The purpose of the present invention is: determines undercarriage turn control lifetime of system evaluation side under the multi-platform use condition of aircraft Method.

The technical scheme is that a kind of aircraft turn steerable system life-span method for testing it is characterised in that according to platform, Continental rise, using damaging ratio to determine the period of test of turning, comprises the steps:

First, determine the damage ratio that platform takeoff and landing and continental rise rise and fall

Undercarriage no matter platform or continental rise using all can to rising and falling between produce and damage.Obviously, the experimental enviroment of platform More harsh.Determine that the purpose damaging ratio is just to determine that the damage of a platform takeoff and landing is equivalent to how many times continental rise and rises and falls.

$\mathrm{\ζ}=\frac{\σ\frac{1}{n_{i.jz}}}{\σ\frac{1}{n_{i.lj}}}$

Wherein:Use for platform, a damage that undercarriage is produced of rising and falling

Use for continental rise, a damage that undercarriage is produced of rising and falling

Second, determine the ratio that platform takeoff and landing and continental rise rise and fall

Provide ratio k that continental rise rises and falls with platform takeoff and landing, this coefficient artificially gives according to the use requirement of aircraft；This coefficient Need to consider to turning system worst situation.

3rd, calculate continental rise and use, using with platform, the number that rises and falls

On 1 and 2 basis, calculate continental rise using peace according to damaging than the ratio risen and fallen with platform takeoff and landing and continental rise Platform is using the number that rises and falls；Formula is as follows:

$\left\{\begin{array}{c}{n}_{lj}+\mathrm{\ζ}\·n_{jz}=n_{jz}\\ \frac{n_{lj}}{n_{jz}}=k\end{array}\right.$

Wherein: n_ljFor continental rise using the number that rises and falls, n_jzFor platform using the number that rises and falls, in formula, k is known quantity；

4th, the turning situation that statistics continental rise rises and falls with platform takeoff and landing

Statistics continental rise uses type and number of times with the turning using each appearance of rising and falling for the platform；Statistical conditions can use matrix M represents:

$m_1=\left[\begin{array}{cc}m11& m12\\ m21& m22\end{array}\right]$

Wherein: m11 represents that continental rise one rises and falls common number of turns

M21 represent continental rise one rise and fall wide-angle traction number of turns

M12 represents that one, platform rises and falls common number of turns

M22 represent one, platform rise and fall wide-angle traction number of turns

5th, calculate the coefficient of reliability of test

Coefficient of reliability is used for ensureing the safety of system；Test cycle number is as follows with the relation of index of aging:

Coefficient of reliability is defined as follows:

${\mathrm{\η}}_{\mathrm{\σ}}=\underset{i=1}{\overset{4}{\π}}{\mathrm{\η}}_i={\mathrm{\η}}_1{\mathrm{\η}}_2{\mathrm{\η}}_3{\mathrm{\η}}_4$

Wherein: η₁, η₂, η₃, η₄It is to consider temperature respectively, destroy degree of danger, load credibility and tired dispersibility Correction factor；

6th, calculate the period of test

Result of calculation according to 1 to 5 step determines the test cycle number of each state in test

$m=m_1\×n\×{\mathrm{\η}}_{\mathrm{\σ}}=\left[\begin{array}{cc}m11& m12\\ m21& m22\end{array}\right]\×\left[\begin{array}{cc}{n}_{lj}& 0\\ 0& n_{jz}\end{array}\right]\×{\mathrm{\η}}_{\σ}.$

The invention has the advantage that

1) new method, based on land airplane undercarriage turning life test, uses the ratio with land use by platform Example can determine that index of aging.

2) if the change of line situation, the impact to undercarriage turn control system can be determined according to service condition.

3) unified land-based test and platform using test, need not have been tested twice, by once test just can be true Determine turn control system lifetim, economical and efficient.

Specific embodiment

It is assumed that the complete continental rise of aircraft uses, the undercarriage life-span rises and falls for 3000.Platform is using the damage using with continental rise Wound ratio is 2.The land number that rises and falls is 2 with the ratio of platform takeoff and landing number.Continental rise is risen and fallen 16 times using one and manipulates turning, 4 tractions Turn；Platform is risen and fallen 16 times using one and manipulates turning, and 2 tractions are turned.

Be can determine by above-mentioned condition:

One, calculate and damage ratio

$\mathrm{\ζ}=\frac{\σ\frac{1}{n_{i.jz}}}{\σ\frac{1}{n_{i.lj}}}=2$

Two, determine land number and the ratio of platform takeoff and landing number of rising and falling

$\frac{n_{lj}}{n_{jz}}=2$

Three, calculate continental rise and use, using with platform, the number that rises and falls

3000=n_lj+2n_jz

$\frac{n_{lj}}{n_{jz}}=2$

Solve: n_lj=1500, n_jz=750

Four, statistics continental rise rises and falls and one turning situation risen and fallen of platform takeoff and landing

$m_1=\left[\begin{array}{cc}m11& m12\\ m21& m22\end{array}\right]=\left[\begin{array}{cc}16& 16\\ 4& 2\end{array}\right]$

Five, calculate the coefficient of reliability of test

${\mathrm{\η}}_{\mathrm{\σ}}=\underset{i=1}{\overset{4}{\π}}{\mathrm{\η}}_i={\mathrm{\η}}_1{\mathrm{\η}}_2{\mathrm{\η}}_3{\mathrm{\η}}_4=5$

Six, life test period is calculated as follows:

$\begin{array}{c}m=m_1\×n\×{\mathrm{\η}}_{\mathrm{\σ}}=\left[\begin{array}{cc}16& 16\\ 4& 2\end{array}\right]\×\left[\begin{array}{cc}1500& 0\\ 0& 750\end{array}\right]\×5\\ =\left[\begin{array}{cc}120000& 60000\\ 30000& 750\end{array}\right]\end{array}$

Result of calculation shows: continental rise situation manipulates turning and carries out 120000 times, and traction turning carries out 30000 times；Platform feelings Condition manipulates and turns is 60000 times, and it is 750 times that traction is turned.

Claims (1)

1. a kind of aircraft turn steerable system life test method is it is characterised in that comprise the steps:

First, determine the damage ratio that platform takeoff and landing and continental rise rise and fall

Determine that the damage of a platform takeoff and landing is equivalent to how many times continental rise and rises and falls:

$\mathrm{\ζ}=\frac{\mathrm{\σ}\frac{1}{n_{i.jz}}}{\mathrm{\σ}\frac{1}{n_{i.lj}}}$

Wherein:Use for platform, a damage that undercarriage is produced of rising and falling

Use for continental rise, a damage that undercarriage is produced of rising and falling

Second, determine the ratio that platform takeoff and landing and continental rise rise and fall

Provide ratio k that continental rise rises and falls with platform takeoff and landing, this coefficient artificially gives according to the use requirement of aircraft, this coefficient needs Consider to turning system worst situation；

3rd, calculate continental rise and use, using with platform, the number that rises and falls

On the basis of step the first and step the second, calculate land according to damaging than the ratio risen and fallen with platform takeoff and landing and continental rise Base uses, using with platform, the number that rises and falls；Formula is as follows:

$\left\{\begin{array}{c}{n}_{lj}+\mathrm{\ζ}\·n_{jz}=n_{jz}\\ \frac{n_{lj}}{n_{jz}}=k\end{array}\right.$

Wherein: n_ljFor continental rise using the number that rises and falls, n_jzFor platform using the number that rises and falls, in formula, k is known quantity；

4th, the turning situation that statistics continental rise rises and falls with platform takeoff and landing

Statistics continental rise uses type and number of times with the turning using each appearance of rising and falling for the platform；Statistical conditions can use matrix m table Show:

$m_1=\left[\begin{array}{cc}m11& m12\\ m21& m22\end{array}\right]$

Wherein: m11 represents that continental rise one rises and falls common number of turns

M21 represent continental rise one rise and fall wide-angle traction number of turns

M12 represents that one, platform rises and falls common number of turns

M22 represent one, platform rise and fall wide-angle traction number of turns

5th, calculate the coefficient of reliability of test

Coefficient of reliability is used for ensureing the safety of system；Test cycle number is as follows with the relation of index of aging:

Coefficient of reliability is defined as follows:

${\mathrm{\η}}_{\mathrm{\σ}}=\underset{i=1}{\overset{4}{\π}}{\mathrm{\η}}_i={\mathrm{\η}}_1{\mathrm{\η}}_2{\mathrm{\η}}_3{\mathrm{\η}}_4$

Wherein: η₁, η₂, η₃, η₄It is to consider temperature, the correction of destruction degree of danger, load credibility and tired dispersibility respectively Coefficient；

6th, calculate the period of test

Result of calculation according to 1 to 5 step determines the test cycle number of each state in test

$m=m_1\×n\×{\mathrm{\η}}_{\σ}=\left[\begin{array}{cc}m11& m12\\ m21& m22\end{array}\right]\×\left[\begin{array}{cc}{n}_{lj}& 0\\ 0& n_{jz}\end{array}\right]\×{\mathrm{\η}}_{\σ}.$