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Rotor failure in housings at high rotational speed is a critical event in the automotive and aerospace industry. The design of the containment housing that encloses the rotor burst is important to ensure the safety of the surrounding area. It is essential to perform rotor containment testing and numerical simulation study. This paper first presents the results of a series of regular disk with same geometry and tube with different thickness containment testing. The disk is made of nickel base alloy and the tube is made of high silicon molybdenum (HiSiMo) ductile iron. The regular disk is released at certain rotating speed which subsequently impacts the inner wall of the tube with uniform thickness. Three groups of tests are conducted at the high speed rotor spin testing facility in the laboratory with different disk rotating speed and tube thickness. Then numerical simulations are carried out using nonlinear finite element method to repeat and study the impact process.

Turbine housing in turbocharger is a critical part which must withstand severe cyclic mechanical and thermal load throughout its service life. The combination of thermal transients with mechanical load cycles results in a complex evolution of damage, leading to thermal mechanical fatigue (TMF) of the material and, after a certain number of loading cycles, to failure of the component. The volute tongue at radial turbine housing is a key feature which is frequently the first location subject to thermal crack failure due to turbine design. Design of tongue is of importance to improve system's TMF performance. In this work, two tongues including square and elliptic shape on radial turbine fatigue are studied. TMF performance is evaluated by finite element analysis (FEA). In particular, experimental method is carried out in order to validate the simulation model. The good agreement is found between numerical and experimental results.

A smart waste gate (WG) turbocharger controls boost by bypassing turbine flow through the WG port which allows optimizing both low and high speed engine performance. However, the WG port in the turbine housing involves much complex geometry which leads to potentially higher thermal stress and plastic strain if design is improper. This paper first presents the common thermal cracking problems at port zone and then shows finite element analysis (FEA) results for one design. The predicted location correlates well with the observed failure port location. A design study with key parameters for the port is conducted under same boundary conditions. Key parameters include height H, inner diameter D and inner diameter fillet r of the port. Totally 13 designs are analyzed under packaging and performance limitation. Accumulated plastic strain (APS) from FEA is used to evaluate different designs. Curves are plotted to show the relationship between APS and design parameters.