Dynamic Analysis Of The Shaft System Of High-speed Atomizer

The high-speed atomizer is the most critical equipment in the spray drying equipment.It must be absolutely reliable.It is widely used in power plant flue gas desulfurization and other fields.The shaft system of high-speed atomizer consists of two rolling bearings,a flexible stepped spindle,a feed assembly,a liquid distributor assembly and an atomization wheel assembly,which is the core part of maintaining high-speed operation.The shaft system received more and more attention.In order to solve the "stuck neck" status and realize the localization of the shaft system of high-speed atomizer,it is necessary to further understand the design mechanism of the core components.The main research content in this paper are as follows:(1)The working principle of the high-speed atomizer is sorted out,the shaft system of high-speed atomizer is established with the software Solidworks and UG,the basic theory of three-dimensional elastic body dynamics and the basic principle of the finite element method are explained,and the Lanczos method is used for simulation to calculate the steps of state analysis.(2)Use the software ABAQUS to perform finite element modeling of the shaft system components of high-speed atomizer,and use the three-dimensional elastic body model to perform modal analysis.The natural frequencies and main vibration modes of the stepped shaft and shaft system under the conditions of no,elastic and rigid constraints are studied respectively,the critical speed corresponding to the rotor system is obtained,and the rated speed of the high-speed atomizer and the other two types of work are determined.The dynamic characteristics of the high-speed atomizer system under elastic and rigid constraints are compared and analyzed.(3)When the working speed is 8000r/min,10000r/min and 13500r/min,the unbalance is equivalently converted into forced excitation to be applied to the shaft.Under different balance accuracy grades,when the shaft is restrainted rigidly,the effect of centrifugal force caused by the unbalanced mass of the shaft on system vibration is calculated.The study found that when the rotation speed is constant,as the balance accuracy grade decreases from G2.5 to G16,the amplitude ratio of the free end increases,indicating that the unbalanced response has a greater impact on the atomizer rotor system.The balance accuracy grade is determined to provide theoretical guidance for actual processing.In order to explore the influence of the horizontal dynamic balancing machine on the vertical shafting,the unbalanced response caused by its own weight was calculated.The study found that the influence of gravity on the rotor system becomes larger with the increase of speed,and the vibration at the free end becomes more obvious.Therefore,when vertical balancing machine is available,try to use it to analyze the flexible shaft.