Modern large aircraft mainly have three power supply systems: Electric Energy, Pneumatic, hydraulic Hydraulics. The energy of the hydraulic system mainly comes from the drive shaft driven by the engine through the gearbox to drive the pump and increase the pressure inside the fluid. When an emergency occurs, if the engine fails to work properly, the hydraulic system can be operated by the power system and the pneumatic system.
The aircraft hydraulic system, as the power source of aircraft flight control system and landing gear, plays a key role in the safe flight of the aircraft. Aircraft hydraulic system of hydraulic pump pulsing output make the pipe produces forced vibration and resonance, if the solid line close to the natural frequency and the resonance frequency of the fluid phase, or with a hydraulic pump pulse frequency is close to, will produce the fluid-structure coupling vibration. Fluid-structure coupling vibration can reduce the service life of hydraulic components and pipes, serious when even will cause the vessel rupture, pipe support structure damage, support rigidity decline, piping system failure, hydraulic oil leak, leading to serious catastrophic accidents. Therefore, make sure the aircraft hydraulic system of fluid-solid coupling for vibration of pipeline flow mechanism, the new hydraulic system for safe and reliable design and vibration suppression measures of existing aircraft hydraulic system is very important.
Aircraft hydraulic pipe system is a typical application of pipeline system, its security good working condition of normal to the plane flying plays an important role, if the hydraulic pipe in larger installation service under stress, vibration at work stress and pressure pulsation stress combination, and easy to achieve early fatigue limit, cracking or breakage, if regularly check and adjust the installation stress, can ensure the normal working state of catheter, effectively avoid cracking and other malignant fault. Our company has cooperated with a unit of air force to develop the prestressed project using Strain Gauge Measurement System (customized) for the hydraulic piping of the hand-held aircraft, and has conducted some verification tests on a certain type of aircraft.
Dynatronic Stress-strain Measurement is used to measure such small changes in resistance, pressure, temperature, velocity and so on.strain gage configurations are based on the concept of a Wheatstone bridge. The general Wheatstone bridge is a network of four resistive arms with an excitation voltage, VEX, that is applied across the bridge.