Summary: | This study analyzes the stress distribution of 3D elastoplastic contact problems by using the FE parametric quadratic programming (PQP) method derived from a 3D FE model based on parametric variational principle (PVP). We numerically analyze a 24-blade compressor by combining centrifugal loading with interference-fit one. To accelerate computation, calculation is simplified by structural modeling via multisubstructuring, aiming to deal with FE-simulated computer aided design (CAD) conveniently. We then analyze the relationships between the maximum residual stresses of the compressor posterior to prestressing and overspeed rpms, and we also study the distribution and magnitude of the contact stresses of the compressor in working conditions after overspeed prestressing. Moreover, we thoroughly discuss the distribution and magnitude of the contact stresses of shaft-shaft sleeve-impeller in working conditions. Relative displacement can be prevented and contact stress can be kept uniform due to the nonuniform initial amount of interference in overspeed prestressing. This paper summarizes the FEM simulation results and provides reference data for improving the design and processing of compressor impellers, indicating that overspeed is indispensable in manufacture.
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