Slurry wear with sand particles in rivers is a serious problem for pump operation. Therefore, a technique to predict wear volume loss is required for selecting wear resistant material and determining specification of the maintenance period. This paper reports a method to predict the wear depth distribution on a blade of an impeller. Slurry wear test of an aluminum pump impeller were conducted. Prediction results of wear depth distribution approximately correspond with the results of slurry wear test. This technique is useful for industrial application.

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In this study, in order to examine the noise measurement technique of the internal flow, the flow noise due to vortex shedding from a circular cylinder was measured by use of a suction type wind tunnel which was equipped with glass wool walls and a condenser microphone. As a result of experiments, it was found that the acoustical free space can be created when the glass wool was set in the test section of wind tunnel, and the measurement of the fluid sound of the internal flow became possible without disturbing a flow field by incorporating a condenser microphone into the glass wool wall. A sound frequency with one big sound pressure level was measured when measuring a fluid sound from a circular cylinder in the fluid flow and the other frequency ingredient was a level as much as the background noise.

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In steam-turbine manufactures, there are two types of design groups, consisting of rotor (shaft) dynamics and blade dynamics groups who work independently. The former mainly calculate critical speed design of the shaft-bearing system. The latter design the off-resonance of blade vibration at higher modes.
However, we have to consider the interaction between shaft vibration and blade vibration concerning the blade modes of nodal diameter k =0 and 1. When concerning the turbine-generators for nuclear power plants, because natural frequency tends to be lower as the blade length increases, blade-shaft coupled vibration effects have to be taken into consideration in designing shafts and blades.
This paper presents a theoretical analysis of coupled vibration between blade vibration in plane (nodal diameter k =1) and shaft parallel motion from the viewpoints of stability and resonance. It also presents an experimental analysis using coupled resonance vibration data, though, with limited conditions.

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