XUE Xiang, LI Yong, LIU Fuguang, et al. Effect of water droplet characteristics on water erosion of stellite alloy for steam turbine blades[J]. Thermal power generation, 2022, 51(7): 116-122.
DOI:
XUE Xiang, LI Yong, LIU Fuguang, et al. Effect of water droplet characteristics on water erosion of stellite alloy for steam turbine blades[J]. Thermal power generation, 2022, 51(7): 116-122. DOI: 10.19666/j.rlfd.202202021.
Effect of water droplet characteristics on water erosion of stellite alloy for steam turbine blades
Steam turbine blades are damaged by water erosion due to the action of steam condensate during operation. Embedding Stellite alloy is a general method to resist water erosion. In this paper
the influence of water droplet speed and size on water erosion of Stellite alloy is studied by numerical calculation. The results show that
the velocity and size of water droplets have a significant effect on the stress of Stellite alloy. With the increase of water droplet collision velocity
the maximum equivalent stress in Stellite alloy increases. When the velocity exceeds 293 m/s
the maximum equivalent stress is greater than the yield strength
and higher secondary stress is produced. With the increase of water droplet size
the maximum equivalent stress increases significantly and exceeds the yield strength of Stellite
but when the water droplet radius exceeds 750 μm
the maximum equivalent stress is basically unchanged. Large water droplets split into smaller water droplets in the process of high-speed collision
and continue to collide with Stellite alloy
resulting in secondary stress that is higher than the fatigue limit of Stellite alloy. The higher the impact velocity and water droplet diameter
the greater the number of secondary stress peaks above the fatigue limit
which will accelerate the fatigue damage of Stellite alloy.