The stagnation temperature profiles which have been observed recently downstream of the stators in high Mach number compressor stages are shown to be due to transport of the rotor wakes across the main streamlines during their passage through the stator. The rotor wake fluid has energy in excess of the inviscid flow, and it is collected by the pressure side of the stator. A wake transport theory is presented, which connects the temperature profile to the rotor blade loss factor, and so provides a new method for determination of the losses in a rotor under actual operating conditions. The theory compares favorably with a special helium-tracer experiment designed to check it, as well as with temperature measurements in two high Mach number stages.

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In this article, we propose a finite element numerical tool adapted to a Fe-based shape memory alloy structural analysis, based on a developed constitutive model that describes the effect of phase transformation, plastic sliding, and their interactions on the thermomechanical behavior. This model was derived from an assumed expression of the Gibbs free energy taking into account nonlinear interaction quantities related to inter- and intragranular incompatibilities as well as mechanical and chemical quantities. Two scalar internal variables were considered to describe the phase transformation and plastic sliding effects. The hysteretic and specific behavior patterns of Fe-based shape memory alloy during reverse transformation were studied by assuming a dissipation expression. The proposed model effectively describes the complex thermomechanical loading paths. The numerical tool derived from the implicit resolution of the nonlinear partial derivative constitutive equations was implemented into the Abaqus® finite element code via the User MATerial (UMAT) subroutine. After tests to verify the model for homogeneous and heterogeneous thermomechanical loadings, an example of Fe-based shape memory alloy application was studied, which corresponds to a tightening system made up of fishplates for crane rails. The results we obtained were compared to experimental ones.