Thermal Deformation Analysis And Optimization Design Of S31 Type Roots Blower Impeller

Roots blower is widely used in various industry departments because of its simple structure,various forms and stable operation.As the one of the important structures of roots blower,roots blower impeller has played a very key role for stable operation.The cooperation of the two impellers in the rotation process is that the precondition for ensuring the gas transmission efficiency,the increase in the temperature of the gas delivery compression process causes uneven thermal deformation of the outer contour of the impeller,with the gap so that the change,resulting in local interference between the two impellers of the Roots blower,aggravation local wear and even lead to "killed".Therefore,the control reduces the thermal deformation of the Roots blower impeller outer contour,so that the impeller remains stable under the actual working conditions,which is of great significance to the normal and stable work of the overall mechanical equipment.This paper focuses on thermal deformation analysis and optimization design of S31 type roots blower impeller,producted by changsha blower factory co.,ltd.,the main research contents and resu ts are as fol ows:Firstly,introduced the performance evaluation index commonly used in the Roots blower,the mechanism of the thermal deformation of the impeller is analyzed,due to the operating principle of the Roots blower determines that it has a higher temperature during the working process,and increases with the pressure of the carrier gas,the theoretical basis of thermal deformation of mechanical parts is analyzed,including heat transfer theory,theory of elasticity,thermal elasticity theory,theory of thermal expansion of material,etc.Secondly,the 3d model of S31 Roots blower was built,the structural characteristics of it was analyzed,and the finite element model of the S31 Roots blower impeller was established.A steady-state thermal analysis was performed on the impeller,obtained it amount of thermal deformation and equivalent stress at temperature rise prepare for the next optimization analysis.Thirdly,in order to prevent the uneven distribution of the temperature change the outer contour of the impeller generates non-uniform thermal deformation,and the deformation of the outer contour leads to the change of the fit clearance.Based on the dissimilarity characteristic of the shape thermal deformation,the impeller balance hole shape is analyzed for the Roots blower impeller influence of the deformation of the outer contour.The optimize hole structure is determined through simulation analysis;The structure of the Roots blower impeller with the smallest amount of thermal deformation is obtained,it make the working life of the Roots blower is extended.Finally,for preventing local interference of the two impellers of the Roots blower,exacerbate local wear and affect the normal running of the Roots blower,the size of the non-mating surface of the impeller is selected as the design variable,with the DOE central composite design principle,the impeller parameterize was optirmized to gain even more reasonable size of the non-mating surface improves the gas delivery efficiency of the Roots blower and perfect its working efficiency.This paper will provide essential parameters and basis for thermal deformation analysis and optimization design of S31 type Roots blower impeller.And it has profound guiding significance for future research of the same type.