| Rotary kiln is the core equipment in the production process of metallurgical industry,building materials industry,chemical industry,special waste treatment industry etc.Components such as cylinder and wheel belt are the key components bearing the rotary kiln’s rotary system.The failure of the key components will lead to the paralysis of the whole rotary kiln working system,resulting in huge economic losses and safety risks.Because the outside of the rotary kiln is wrapped with high temperature flue gas jacket to heat it,the distribution of temperature field is directly related to the mechanical properties of key components of rotary kiln.In this thesis,the temperature field control,static and dynamic characteristics of key components of rotary kiln and the optimization of flue gas jacket structure are studied by means of thermal-fluid-structure coupling finite element analysis technique.Firstly,aiming at the problem that the temperature of the rotary kiln cylinder is difficult to be directly measured,a finite element model of flow field analysis is created based on the basic principle of fluid-thermal coupling analysis.The temperature field distribution of the high-temperature flue gas in the flue gas jacket outside the cylinder and the outside wall of the cylinder is verified by numerical simulation method,and the influence of different flue gas velocity and jacket clearance on the temperature field distribution of the flue gas field and the outside wall of the cylinder is explored.The problem of large axial temperature distribution gradient is solved by optimizing the flue gas jacket flow field.Secondly,the static analysis of the influence of thermal stress on the mechanical characteristics of key components of rotary kiln is carried out,and the static analysis model is created based on the thermal-fluid-structure coupling analysis method.By comparing the mechanical characteristics of key components of rotary kiln in cold state and hot state,the influence of thermal stress on the stress distribution,deformation trend and contact clearance between transmission components is explored.Aiming at the problem of stress concentration at the head end of the cylinder kiln,the temperature field distribution on the outer wall of the cylinder is optimized by improving the flue gas jacket structure,and the influence of different flue gas jacket structure on the stress field at the head end of the rotary kiln is compared and analyzed.Finally,aiming at the problem that the contact clearance between key components of rotary kiln affects the dynamic performance,a transient dynamic analysis model is established based on the basic theory and method of transient dynamics and considering the factors of multi-field coupling and nonlinear contact.The influence of different side clearance on the meshing law of key components and the influence of different side clearance,speed and temperature field on the impact force law in the rotation process of rotary kiln are explored. |
