Arbitrarily time-distributed velocity information acquired by laser Doppler velocimeter systems needs special care when evaluated wrt. the mean velocity and the components of the Reynolds stress tensor. In rotating machinery, the arrival time information can be uniquely mapped to the angular position u of the runner blades by using encoder signals relating a ®xed runner position to an arrival time. It is convenient to statistically evaluate the velocity information of the detected particles in an angular window u 0 À Du=2; u 0 Du=2 in order to obtain mean velocities and turbulence values for an angular position u 0 . This approach has the inconvenience that turbulence values calculated from standard deviations are in¯uenced by a possible variation in the mean velocity in the evaluation window. Other problems that arise with this``evaluation window'' method are the in¯uence of unevenly angular-distributed velocity information on the mean velocity or the poor resolution of maxima and minima of the mean velocity, which is similar to the problem pointed out by Jakoby et al. but being of second-order nature. In this paper, different improvements in thè`e valuation window'' method wrt these problems based on ideas found in a paper by McDonald and Owen are presented. A con®dence interval calculation, generalizing the methods of Boutier, for all calculated values is included, which allows an appropriate window size Du to be chosen for each particular situation. The different methods are compared using examples from wake¯ows of axial hydraulic turbomachinery measured in air and water.

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This paper investigates the reversal of magnetic nanowires via a perturbation argument from the static case. We consider the gradient flow equation of the micromagnetic energy including the nonlocal stray field energy. For thin wires and weak external magnetic fields we show the existence of travelling wave solutions. These travelling waves are almost constant on the cross section and can thus be seen as moving domain walls of a type called transverse wall.

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In numeric simulations of magnetic nanowires several groups have observed two different types of reversal modes. It is suggested that the reversal mode corresponds to an energetically optimal domain wall profile. We investigate the energy minimisation problem in different regimes of thickness. When the radius goes to zero, the energy minimisation problem Γ‐converges to a reduced local one dimensional problem. Thus for small radii, minimisers of the energy functional are almost constant on the cross section. This is not the case for big radii. For radius to infinity, a class of magnetisations with a vortex has the optimal energy scaling. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)