Two blade curvatures representative of those found in automotive fans are compared.Measured performances are analyzed for forward and backward curved blades, either with orwithout heat‐exchangers placed in front of them. The backward fan demonstrated good efficiencybut poor acoustics, whereas it is the contrary for the forward fan. Investigations are completed by anumerical analysis of the flow in the cooling module. Different integration effects are highlighteddepending on the blade curvature, showing variation in pressure, torque and efficiency. Analysesof blade loadings show that the flow is more homogeneous with a forward curved fan and itproduces less unsteadiness at the blade tip. Post‐processing of detached eddy simulations (DES)shows density fluctuations on the blade wall and confirms the correlation between the large vorticalstructures and the acoustic sources for both fans. In addition, with the forward fan, the soundpropagation is less directed towards the axis of rotation and it yields up to −3.6 dB of sound pressurelevel (SPL) measured in front of the cooling module. As a conclusion, any choice for a fan mustresult from a compromise between aerodynamics and aeroacoustics, and the final performancesmust be carefully checked on the module.

In this paper, we consider a mathematical model of a contact problem in thermo-electro-viscoelasticity with the normal compliance conditions and Tresca’s friction law. We present a variational formulation of the problem, and we prove the existence and uniqueness of the weak solution. We also study the numerical approach using spatially semidiscrete and fully discrete finite element schemes with Euler’s backward scheme. Finally, we derive error estimates on the approximate solutions.

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