A new indirect method of determining the rheological behavior of a non-Newtonian fluid, modeled by a two parameter power law, flowing in a tube with a geometrical singularity is proposed which makes it possible to indirectly estimate the rheology. Due to this singularity, the shape of the velocity profiles can be strongly dependent on the fluid rheology, which makes it possible to obtain indirectly the required viscosity estimation. Non-Newtonian fluid flows were simulated numerically with various flow conditions. Based on the results of these calculations, plots were drawn emphasizing the dependence of the dimensionless velocity on the dimensionless rheological parameters. On the other hand, dimensionless velocities were also obtained by measuring velocity profiles with an ultrasonic Doppler velocimeter. These experimental values were put on the plots and the rheological parameters of the actual fluid were thus determined. Comparisons were made with viscometer measurements in order to assess the accuracy of the method and its range of validity. This method is of great potential interest for application to industrial processes when it is necessary to know the viscosity of a fluid undergoing a transformation without interrupting the process by taking fluid samples.

A series of 44 samples of bone wedges of human origin, intended for allograft openwedge osteotomy and obtained without particular precautions during hip arthroplasty were re-examined. After viral inactivity chemical treatment, lyophilisation and radio-sterilisation (intended to produce optimal health safety), the compressive strength, independent of age, sex and the height of the sample (or angle of cut), proved to be too widely dispersed [10 − 158 MPa] in the first study. We propose a method for selecting samples which takes into account their geometry (width, length, thicknesses, cortical surface area). Statistical methods (Principal Components Analysis PCA, Hierarchical Cluster Analysis, Multilinear regression) allowed final selection of 29 samples having a mean compressive strength σmax = 103 MPa ± 26 and with variation [61 − 158 MPa] . These results are equivalent or greater than average materials currently used in openwedge osteotomy.

This study is to look at the distribution of current densities in proton exchange membrane fuel cells (PEMFC) to enable optimisation of fuel cell performance. The feasibility of using a new measurement technique of the local magnetic field, in the conductive plates of the cell was studied. The magnetic field is measured throughout the cell using the Maxwell equations and the current densities calculated. The measurement system and its validation are outlined in the first section. The next section outlines the experimental current density distribution within the cell, operating under standard conditions and special configurations, such as the partially active membrane electrodes assembly (MEA). Using a Matlab or Femlab model of the cell, (which is briefly outlined) our experiments are compared and an attempt made to explain the distribution of the current densities. Finally recent developments of the device are described, which will be used in several tests of PEMFC small stacks.