Study On Anti-erosion Mechanism Of High Speed Impact Of Fine Particles On Grooved Blade Target

Erosion wear is a process in which solid particles or fluids impact the workpiece surface at a certain speed and angle,causing surface damage and material removal.The erosion phenomenon caused by the impact of fine solid particles on the surface of materials is widely found in many engineering fields.For example,thermal power generation,aerospace,oil and gas transportation,high-speed railways,machinery manufacturing,mining operations,etc.Existing studies show that high speed impact of solid particles is the main failure mode of key components of mechanical and energy power equipment,such as steam turbine,gas turbine,centrifuge blade,automobile water pump impeller,valve,steam runner and so on.It has become one of the main factors affecting the safety and economy of equipment operation.Therefore,it is of great significance to explore the influence of impact parameters,target plate structure and other key factors on the erosion performance and particle rebound characteristics,so as to effectively reduce and accurately predict the erosion failure of fine solid particles.In addition,it is of great significance to improve the service life of equipment and reduce the production cost.Based on the nonlinear explicit dynamics algorithm,this paper studies the erosion and wear mechanism and springback characteristics of the non-smooth surface of biological surface（lizard back）under different groove microstructures.Based on this,it could be used to optimize the corrosion resistance of the key components of the transport power equipment.The specific research content and results are as follows:（1）The erosion models of single particle impact flat target plate,corrugated target plate and circular arc target plate were established.The effects of particle incidence angle,velocity and target plate structure on the rebound characteristics and erosion behavior of particles were analyzed by finite element method.The results show that:the recovery coefficients of particle velocity under flat target plate decrease with the increase of original impact angle;in a certain range of angles,the erosion resistance of the target plate with grooves is better than that of the flat target plate.（2）Based on the study of single particle,the erosion models of multi-particle impact on flat target plate,circular arc and V-shaped groove structure target plate are established.Furthermore,the influence rules of incident velocity,incident angle,target plate structure and other parameters on the erosion behavior and the potential erosion mechanism are further explored under the impact of multiple particles.The results show that:under certain incidence velocity and angle,the erosion resistance of circular arc and V-shaped slot structure is better than that of the flat target.And the larger the ratio of arc radius R to particle radius r,the better the average erosion resistance of circular arc structure.Therefore,among the three different circular arc structures（R/r=2,5,10）,the average erosion resistance of the circular arc structure target plate corresponding to R/r=10 is the best,and the average erosion resistance of the circular arc structure target plate is improved by27.20%compared with the flat target.Similar to circular arc structure target plate,the larger the ratio of groove spacing L₁ to particle radius r,the better the average erosion resistance of V-shaped groove structure target plate.Therefore,the average erosion resistance of the V-shaped groove structure corresponding to L₁/r=10 is the best among the three V-shaped groove structures（L₁/r=2,5,10）with different characteristic sizes,and the average erosion resistance of the V-shaped groove structure is improved by 20.21%compared with that of the flat target.To sum up,when the incidence velocity is constant,in the incidence angle range of 24°～45°,the circular arc structure target plate corresponding to R/r=10has the best anti-erosion performance.