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Turbine housing divider wall design is critical to guarantee a sufficient lifetime. A numerical simulation is a necessary step toward the understanding of behaviors of divider wall subjected to cyclic thermal loading. Calculating the temperature and plastic strain distribution at the divider wall, steady state and transient, can predict crack initiation. A two-dimensional finite element model for divider wall has been developed, which takes into account transient state film heat transfer convection, temperature-dependent strain hardening behavior and cyclic thermal loads. A three-dimensional model is also presented to validate this model. Simulation results include temperature and plastic strain at divider wall are compared. The paper also studies the influences of turbine housing wall thickness, divider wall thickness and the connection angle between both walls on divider wall.

Numerical method is popular in analyzing turbine housing in turbocharger with an early and rapid risk assessment. However, complex casting and extreme thermal loading from exhaust gas temperature and flow variation under engine duty cycle lead to big thermal stress and this makes material serviced in the plastic zone. Previous numerical simulations show that a mesh size is insensitive to the elastic finite element analysis (FEA), but might not be proper for elastic-plastic FEA, even that other boundary conditions keep same, which indicating simulation results are changeable with mesh size and a simple numerical mesh size convergence might not be enough to guarantee accurate numerical results as well. Therefore, several different mesh sizes are used in elastic-plastic analysis of turbine housing to investigate the influence on numerical results.

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.

In this work we have proposed an interesting clamping solution of V-band which has an important industrial impact by reducing the cost and assembly process as well compare to the traditional V-band. The design what we are focusing for is applied for all size of turbochargers which helps to connect the hot components such as manifold and turbine housing. The cost for V-band is mainly from T-bolt. It is made from special stainless steel which represents 50% of the total cost. In this work it is proposed a new V-band joint by changing bolt clamping status from tension to compression. From tension to compression we change the bolt material from high cost steel to low cost steel. The new total cost is reduced by 40%. The prototype is made and performed in static tests including anti-rotating torque test and salt spray test. The new joint meets the design requirements at static condition. Further work will focus on the dynamic qualification and at high temperature as well.

Turbochargers are widely used to boost internal combustion engines for both on and off high way applications to meet emission and performance requirements. Due to the high operating temperature, turbochargers are subjected to hostile environment. Low vibration level is one of the key requirements while designing turbo for every application. An engine bracket is employed to support turbine housing to reduce total vibration level. Turbine housing in the turbocharger is commonly equipped with boss to accommodate the engine bracket supporting which eventually includes additional constraints in the turbocharger system. Additional constraints in the turbine housing can lead to adverse impact in the Thermo-Mechanical Fatigue (TMF) life of the housing component. Boss generally has critical influence to thermal stress distribution of the turbine housing.

Turbocharger is widely used to boost engine due to emissions, fuel and cost reasons. As one of the hot components, it is subjected to severe temperature and thermal load history. Under these conditions, the material suffers hostile thermal mechanical fatigue (TMF) damage especially for the turbine housing side which absorbs hot exhaust gas directly to drive the turbine wheel. The cracking of turbine housing occurs frequently in the inlet flange location due to its very complex geometry and consequently complicated temperature and stress distribution, seriously affecting the normal operation of the engine. In the electric power industry, one of the most challenging tasks is to ensure the guaranteed lifetime. This paper proposes a novel turbine housing inlet flange design to control this type of failure effectively and improve the component lifetime and reliability. The novel design extends the inlet flange and includes the heat dissipation function as well.

V-band joint was originally developed during World War II by the Marmon Corporation for use in the aircraft industry. The U.S. Military used Marman clamp to secure the atomic bombs during transport at the end of the Second World War. It has been widely used in a variety of applications including pumps, engines, exhaust systems, turbochargers to offer effective fastening solutions and greatly simplify assembly and service. In addition, the orientation of the connected components can be easily adjusted according to customer's request. So it has been popularly adopted in the field of turbochargers. The axial clamping force and anti-rotating torque are two key parameters in turbocharger applications to verify the quality of the v-band joint during its operation. It is important for the v-band joint to have sufficient axial clamping force to prevent leakage and wheel damage.