| Viscose fiber is widely applied in many fields in our life,such as paper,medicine,textile,printing.etc.As a result,it will produce much water with acid and alkali waste which will pollute the environment seriously without some physical and chemical treatment.Generally speaking,if the waste water is dealt with some physical and chemical treatment,it will ultimately become sludge with the water rate of 97%.Then the sludge is separated through the centrifuge and less than 80%of moisture content of sludge will be got,which may receive some following-up treatment.Since centrifuge plays an important role in the sewage treatment process,to study the strength,deformation,and its characteristics of the internal flow in the running process of a centrifuge,this paper analyzes the rotary drum and screw conveyer by means of the finite element method,and explores the characteristics of the internal flow field through the method of fluid mechanics.Specific work is as follows:1?It analyzes a three-dimensional finite element model of decanter centrifuge drum and screw conveyer by static method.It checks the force of the drum under the joint function of the centrifugal force and the hydraulic combined with the design of pressure vessels.Meanwhile,it investigates the effects of axial and radial displacement.Moreover,the paper makes a numerical modeling and analysis of the blade's stress and displacement of the screw conveyor under no-load and spiral condition.The results show that under normal working conditions,the drum,the third stress intensity of the screw conveyor and the deformation of the axial and radial direction meets the requirement of real production.The maximum stress value of the drum is located at the heel of the inner wall of the cylinder;the maximum stress of the screw conveyor is located at the root of the spiral blade.2.By the establishment of a finite element model of the internal fluid of decanter centrifuge,the RNG k-epsilon turbulence model is adopted.The paper analyzes the flow velocity,pressure and the distribution of turbulent kinetic energy through the fluid analysis of CFX module,and discusses the relationship between the three characteristics and the centrifuge separation of horizontal decanter.It also studies the sludge separation process of the decanter centrifuges through the transient analysis method.Besides,by changing the rotation speed and the rotate speed of the drum,the article studies the numerical relationship between the technical parameters and the slag discharging port of the sludge moisture content.It shows that in a certain range,the rotational speed difference has an optimal value,but rotational speed of the drum has little influence on the real separation effect,compared with the rotational speed difference. |
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