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Documents a case study in the use of Shainin Design of Experiments in an industrial honing operation. Provides an overview of the process which attempts to reduce process variability by isolating the most influential factor (Red X). Shows the details of the week‐long experiment and gives some analysis of the data. Uses multiple statistical techniques to identify Red X and discusses corrective action. Suggests that this methodology is very practical and easily executable in many settings, making it one of the most approachable quality techniques available.

TEST bed equipment plays no small part in the comparatively high standard of efficiency of the modern aero‐engine, and a lot of time has been given to the careful study of engine test requirements by equipment designers.

THE fact that ring cowling is approved for use with the current series of Mercury and Pegasus engines appears a suitable occasion for a resumé of the important development work carried out by the Bristol Company in connection with the application of drag‐reducing cowlings to their engines and a programme of work which has included a long series of single cylinder experiments, wind tunnel research and full scale flight tests.

Problem 1 of the International Workshops for Eddy Current Code Comparison is a hollow cylinder with axis perpendicular to a uniform field. A total of 17 solutions are described and compared with experimental results. Many kinds of codes, both two‐ and three‐dimensional, were found to give satisfactory solutions.

This study aims at investigating two-dimensional laminar flow of power-law fluids around three unconfined side-by-side cylinders.

The numerical study is performed by solving the governing (continuity and momentum) equations using a finite volume-based code ANSYS Fluent. The numerical results have been presented for different combinations of the governing dimensionless parameters (dimensionless spacing, 1.2 = L = 4; Reynolds number, 0.1 = Re = 100; power-law index, 0.2 = n = 1.8). The dependence of the kinematic and macroscopic characteristics of the flow such as streamline patterns, distribution of the surface pressure coefficient, total drag coefficient with its components (pressure and friction) and total lift coefficient on these dimensionless parameters has been discussed in detail.

It is found that the separation of the flow and the apparition of the wake region accelerate as the dimensionless spacing decreases, the number of the cylinder increases and/or the fluid behavior moves from shear-thinning to Newtonian then to shear-thickening behavior. In addition, the distribution of the pressure coefficient on the surface of the cylinders presents a complex dependence on the fluid behavior index and Reynolds number when the dimensionless spacing between two adjacent cylinders is varied. At low Reynolds numbers, the drag coefficient of shear-thinning fluids is stronger than that of Newtonian fluids; this tendency decreases progressively with increasing of Re until a critical value; beyond the critical Re, the opposite trend is observed. The lift coefficient of the middle cylinder is null, whereas, the exterior cylinders experience opposite lift coefficients, which show a complex dependence on the dimensionless spacing, the Reynolds number and the power-law index.

The flow over bluff bodies is a practical engineering problem. In the literature, it can be seen that the previous studies on non-Newtonian fluids are limited to the flow over one or two cylinders (effect of an odd number of cylinders on each other). Besides that, the available results concerning the flow of Newtonian fluids over three cylinders are limited to the high Reynolds numbers region only. However, this work treats the flow of non-Newtonian power-law fluids past three circular cylinders in side-by-side arrangements under a wide range of Re. The outcome of the present study demonstrates that the augmentation of the geometry complexity to three cylinders (effect of pair surrounding cylinders on the surrounded ones in what concerns Von Karman Street phenomenon) causes a drastic change in the flow patterns and in the macroscopic characteristics. The present results may be used to predict the flow behavior around multiple side-by-side cylinders.

Hydraulic cylinders may not be the most glamorous components in industrial robots but they are here to stay.

£2.25m expansion at Milton Keynes for pneumatic/hydraulic equipment manufacturer