简介

宫内直先生1978年毕业于日本京都大学机械工程系，2004年获得工学博士学位，日本机械协会会士（JSME Fellow）。曾在日本久保田（Kubota）株式会社供职长达三十四年，从事大型透平泵、供水工业标准、小水电相关技术研究，历任久保田株式会社研究员、主任研究员、研究部门负责人。在长期的实际工作中，积累了极其丰富的工程经验，在日本透平机械工业领域享有盛誉。

宫内直先生自2015年起任大阪工业大学工学部机械工学科兼职教授。

Abstract

Using the optimization design and the inverse design, the pump design method becomes to establish. Therefore, nowadays the pressure fluctuation which sometimes induces vibration or noise severely is focused and it has begun to be studied by using EFD/CFD Integration method. As for the guide vane of mixed flow pump, due to the distortion caused by Jet-Wake flow from the impeller and rotor-stator interaction, the flow unsteadiness causes problems of vibration. Because guide vane is narrow and complicated three-dimensional shape, it is difficult to measure the pressure. The technology of stereolighographic model with plenty fine pressure pipes was used to manufacture a guide vane. And accurate and sensitive multipoint simultaneous measurements with high spatial and temporal resolution were done. Next, using various statistical analyses including higher order statistics (skewness S and kurtosis K), the characteristics of the measured pressure is examined: 1) The mean pressure distributions at the design flow rate are as intended by an original design. 2) At shutdown, there is the bimodality in the histogram of the inlet hub near the pressure surface of guide vane. This would be caused by two region of Jet-Wake flow. 3) At the immediate downstream, mixed diffusion process with the main flow would cause a kind of relaxation process from this unsteady flow to a steady flow with periodic pressure fluctuation.