The invention provides a frequency measurement method suitable for a star-shaped flexible hub helicopter blade, which comprises the following steps: moving a lifting hook 3 above a blade tip of a blade to be measured, supporting a lifting belt 2 at the lower part of a blade tip airfoil and tying the lifting hook, so that the lifting hook hangs the blade tip of the blade, and measuring and adjusting the length of the lifting belt. The swing inherent frequency of the hanging system is less than 1/5 of the first-order bending frequency of the paddle; the swing inherent frequency # imgabs0 # g of the hanging system is the gravitational acceleration, and L is the length of the hanging belt; a plurality of knocking points are arranged from the root of the blade to the tip of the blade in a matrix mode, each knocking point is knocked once in each measurement, and the inherent frequency of the blade is obtained through measurement of a three-axis vibration sensor. According to the invention, the constraint mode of the blade root can be accurately simulated, the action of the centrifugal force when the blade works is simulated by hanging the spring rope, and the inherent frequency of the blade in a non-rotating state can be more accurately and truly measured. A test result and a calculation result are shown in a table 1.
本发明提供适用于星型柔性桨毂直升机桨叶的频率测量方法,其中包括步骤将吊钩3移动至待测桨叶的桨尖上方,用吊带2托在桨尖翼面下部并系于吊钩,使得吊钩吊挂住桨叶的桨尖,测量并调节吊带长度,保证吊挂系统的的摆动固有频率小于桨叶一阶弯曲频率的1/5;吊挂系统的摆动固有频率#imgabs0#g为重力加速度,L为吊带长度;从桨叶根部到桨叶尖部矩阵式布置多个敲击点,每次测量均在各个敲击点进行一次敲击,通过三轴振动传感器进行测量得出桨叶固有频率。本发明能够准确的模拟桨叶根部的约束方式,同时又通过弹簧绳吊挂模拟桨叶工作时离心力的作用,可以更加准确、真实的测量桨叶在不旋转状态的固有频率。测试结果与计算结果如表1所示。
Frequency measurement method suitable for star-shaped flexible hub helicopter blade
适用于星型柔性桨毂直升机桨叶的频率测量方法
11.04.2025
Patent
Elektronische Ressource
Chinesisch
IPC: | G01H MEASUREMENT OF MECHANICAL VIBRATIONS OR ULTRASONIC, SONIC OR INFRASONIC WAVES , Messen von mechanischen Schwingungen oder Ultraschall-, Schall- oder Infraschallwellen / G01M TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES , Prüfen der statischen oder dynamischen Massenverteilung rotierender Teile von Maschinen oder Konstruktionen / B64F GROUND OR AIRCRAFT-CARRIER-DECK INSTALLATIONS SPECIALLY ADAPTED FOR USE IN CONNECTION WITH AIRCRAFT , Boden- oder Flugzeugträgerdeckeinrichtungen besonders ausgebildet für die Verwendung in Verbindung mit Luftfahrzeugen |
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