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This paper describes a numerical analysis of flow in an induction-type electromagnetic pump. Laminar and turblent flows in a conducting fluid between two coaxial cylindrical walls to which were applied an azimuthally traveling sinusoidal magnetic field are investigated numerically. In order to consider the demagnetizing effect quantitatively, induced magnetic fields due to induced currents are calculated based on the Biot-Savart's law. Several characteristic curves are obtained from numerical results. They are characterized by the Hartmann number, magnetic Reynolds number, azimuthal pressure gradient, pole pitch and curvature of the channel. Influence of these parameters on the flow are discussed in detail.

A numerical method calculating the two-dimensional MHD laminar and turbulent flow in a traveling sinusoidal magnetic field is shown. Some calculated examples which represent the relations between the induced mean velocity and Hartman number, magnetic Reynolds' number, traveling velocity of the magnetic field, wavelength of the field, etc., are shown. Some characteristic curves as a flat linear induction pump are calculated.

Recently there has been a heavy increase in the demand for volute pumps handing viscous fluids for chemical industries. It is suggested that the properties of viscous fluid influence the hydraulic performance of a centrifugal pump as compared with action of water, and already a few scholars have reported on this influence. It seems, however, that there remain many problems unsettled as to the pumping behavior of a volute pump handling viscous fluids. The authors measured the hydraulic performance characteristics of a 75 mm volute pump under various pumping conditions in order to analyze their characteristics. In this paper they describe the method of representing all the properties under various conditions and show the performance characteristic diagrams indicating the influence of viscosity.

When solid particles flow through the impeller of a volute pump with water, the behavior of particles is not always clear. The writers recorded photographically the trajectories of solid particles in the impeller using a high speed camera. In this paper the experimental results are cited, especially those on the relative velocity and its direction at the impeller exit. Moreover the numerical method of calculating the trajectories is demonstrated.

The flow through volute pump is so complicated that the accurate values of the pressure losses are not obtainable by calculation. In this paper the writer treats of the pressure loss as the difference between the head handling water and that handling viscous fluids other than water, and derive the formula which predicts the heads of volute pump handling viscous fluids from the head of water.

Recently, the Gibson method has been used for flow measuring at hydraulic power plants, but the obtained results have never been compared with volume or weight measurements. Therefore the accuracy of the method is uncertain. Authors made comparative experiments between the weight measurements and the Gibson method by means of a test apparatus of 3 in. diameter pipe line. As a result of the tests, the relative errors of the Gibson method were found to be positive for rapid gate closure, and negative for slow gate closure. The variations of discharge did not affect the discrepancies. The authors proposed such a new treatment of fluid friction coefficient in the Gibson method analysis that the relative errors might become smaller particularly for slow gate closure.

As to the formula predicting the efficiency of prototype water turbines by their model tests, many formulas have been already presented by many investigators and are used practically. It seems, however, these formulas are not always exact as to treatment of hydraulic pressure losses. In this paper the authors show the method predicting the efficiency of prototype water turbines using the model test data at different speeds. By this method more precise values of the efficiency can be obtained. A similar calculating method is applied to the test data using the different size models also.