Research On The Mechanism And System Implementation Of Laser Cleaning Of Airport Runway Surface Dirt

As the main carrier of aircraft operation,the airport runway is the core facility of the airport.With the continuous growth of my country’s civil aviation flight volume and the increasingly complex airport layout,runway safety issues have become prominent.The dirt attached to the runway of the airport will reduce the friction coefficient of the runway,causing the aircraft to fail to take off or land normally,and bringing huge safety hazards to the flight of the aircraft.Therefore,major civil aviation airports regularly check the dirt adhesion on the airport runway,test the friction coefficient of the runway,and remove the dirt on the surface of the airport runway to ensure the normal friction characteristics of the airport runway surface.The traditional method of removing dirt from the runway surface of the airport is ineffective.The steel wire and metal shot blasting used in mechanical cleaning are scattered on the runway,which is easy to be sucked into the aircraft engine,causing the crash of the aircraft;the water pressure of the high-pressure water gun cleaning is relatively high(40MPa),Improper operation of the equipment will bring harm to the human body and the road surface.In winter,there is a problem of ice on the runway;chemical cleaning is not conducive to environmental protection and human health,and strict waste disposal is required.Laser cleaning technology is a safe and effective cleaning method,and the research on its mechanism and process has a great demand in the field of airport runway dirt cleaning.In this research,through the analysis of the mechanism of pulse laser cleaning,the feasibility and application of pulse laser cleaning the dirt on the surface of the airport runway are studied by combining the three-dimensional finite element model and the experiment.The main research contents are as follows:(1)Mechanism analysis of pulsed laser cleaning runway dirt.The process of material absorbing pulsed laser energy includes gasification mechanism,thermoelastic stress,light stripping mechanism and other mechanisms.These several action mechanisms interact and affect the cleaning efficiency and quality during the cleaning process,and can change the dominant action mechanism of pulsed laser parameters.(2)Analysis of the type,composition and properties of runway pavement materials and typical dirt materials on their surfaces.Carry out on-the-spot investigation and statistics of airport runway pavement and dirt types at Zhengzhou Xinzheng International Airport,and select cement concrete pavement and glue accumulation as the main research objects.X-ray diffractometer and Fourier transform infrared spectroscopy were used to carry out quantitative and qualitative research on the cement concrete pavement samples and rubber-stacked samples of Zhengzhou Xinzheng International Airport,respectively,and test their main properties.It provides a theoretical basis for the follow-up pulsed laser cleaning finite element analysis model and experiment.(3)Three-dimensional finite element model modeling and simulation of pulse laser cleaning airport runway dirt.Study the influence of different pulse laser parameters:scanning speed,laser power,on the temperature field and surface morphology of the pulse laser cleaning process.The results show that the scanning speed is 1000mm/s,the repetition frequency is 50 k Hz,and the laser power is 10 W,which has suitable cleaning efficiency and cleaning quality.(4)The experimental system design and performance verification of the pulsed laser cleaning cement concrete surface area glue was carried out.Design the pulse laser cleaning system,and design the experimental scheme based on the results of the pulse laser finite element model.The surface friction coefficient of cement concrete before and after cleaning was measured.The results show that the surface friction coefficient of cement concrete samples after pulse laser cleaning fully meets the actual work requirements.It is safe,effective and feasible to use pulse laser to remove the dirt on the airport runway surface.