The Research On Twisted Tube Of Surface Erosion And Collision Dynamics By Fluidized Particle

It’s an important means of using liquid-solid two-phase flow in heat transfer equipment to enhance heat transfer and remove scaling. It’s an important part of using twisted tube with induced fluidized particles in the liquid-solid two-phase flow technology. Particle phase collide with the wall and scratch on the tube wall which actually is the collision and erosion effect by the particles. This article just from the perspective of collision and erosion to do the following work:Using the software of Fluent to simulate fluidized particles colliding in the inner wall of the twisted tube and simulate the erosion of fluidized particles. Considering five factors(fluid flow velocity, twist tube’s ovality, twisted tube’s lead, particle size, particle concentration) and two-level’s operating parameters to do orthogonal analysis. Under the different operating parameters, the average erosion rate within different operating parameters and the primary and secondary factors’ effect on the average erosion rate has been obtained.For the spiral flow inducing fluidized particles lead to the collision and erosion on surface is inhomogenal within the twisted tube, the five factors and two levels’ operating parameters were optimized to obtain a good uniformity on the wall surface by the fluidized particles in the operation parameters. In order to avoid particles to descaling blind, the simulated results show that within a given range of operating parameters there are two sets of operating parameters can make a good uniformity in the wall surface erosion by the abrasive particles, the average erosion rate is not low, uniformly optimized surface erosion better operating parameters of a particle in two twisted tube welcome stream surface, back flow surface’s erosion rate difference is narrowed. But it is inevitable that the rate of erosion in the distortion of straight pipe and inlet transition section by fluidized particles is very small.Though the discrete element software EDEM coupled Fluent to simulate fluidized particles’ motion in the twisted tube to obtain the kinetic parameters associated with particles. The microscopic parameters obtained can explain the fluidized particle size of the average erosion rate on the inner wall and surface erosion uniform issues in the twisted tube. The average erosion rate is due to its large impact force on the wall surface. The abrasive surface is good uniformity due to a high collision probability of the particles.Through the established fluidized bed experiment platform, spiral fluidized heat transfer experiments about fouling materials with ammonium chloride solution was did. The results showed that adding balls fluidized particles can remove scaling and enhance heat transfer effect online. The calculated erosion and removal capability of particles about two millimeter size is 0.152 mm to the wall for the chloride crystal scaling. The erosion and removal capability of particles about two millimeter size is 0.152 mm to the wall for the chloride crystal scaling.