Search Results 1-20 of 117

  • Relation between peak value and acoustic damping of sound pressure level of one dimensional sound field partitioned by perforated plates  [in Japanese]

    ISHIHARA Kunihiko , GOTO Akari

    … In this study, the sound pressure level of the one dimensional duct with the perforated plate will be calculated by the transfer matrix method in various parameters such as the aperture ratio, the hole's length and the set position of the plate. …

    The Proceedings of Mechanical Engineering Congress, Japan 2019(0), J09110, 2019

    J-STAGE 

  • On sound pressure level of one dimensional sound field partitioned by perforated plate:(Effect of hole length on acoustic natural frequency of duct)  [in Japanese]

    Ishihara Kunihiko , Kudo Satoru

    <p>Noise prpblems sometimes occur due to a self sustained tone in a heat exchaneger such as a boiler and a gas heater. Once it happens the factory is obliged to stop an operation. So it is very …

    The Proceedings of Conference of Kansai Branch 2019.94(0), 704, 2019

    J-STAGE 

  • Consideration of acoustic natural frequency of one dimensional sound field partitioned by perforated plate:(1<sup>st</sup> Report; Consistency of present analysis with Melling equation)  [in Japanese]

    ISHIHARA Kunihiko

    … An natural acoustic frequency of an one dimensional duct partitioned by a perforated plate was clarified to come down with decreasing aperture ratio experimentally and analytically. … As a result, it was clarified that the Transfer Matrix Method can be used in prediction of the natural acoustic frequency of the one dimensional duct with the perforated plate. …

    The Proceedings of the Symposium on Environmental Engineering 2018.28(0), 127, 2018

    J-STAGE 

  • Effect of set position of perforated plate on acoustic natural frequency of one dimensional sound field  [in Japanese]

    KUDO Satoru , ISHIHARA Kunihiko

    … This paper deals with the effect of the set position of a perforated plate on the acoustic natural frequency of an one dimensional sound field partitioned by the perforated plate. … The acoustic experiments using the one dimensional duct partitioned by the perforated plate and the numerical analysis by the transfer matrix method were conducted. …

    The Proceedings of the Symposium on Environmental Engineering 2018.28(0), 128, 2018

    J-STAGE 

  • Acoustic natural frequency of one dimensional sound field partitioned by perforated plate:(Effect of hole length on acoustic natural frequency of duct)  [in Japanese]

    Ishihara Kunihiko , Kudo Satoru

    … <p>Karman vortex shedding occurs when the gas passes through the duct with tube bank of the heat exchangers, such as gas heaters and boilers. … Very high level sound in called "self-sustained tones" occurs due to the interference of the vortex and the sound field in the duct. … Then, perforated plates are installed in both sides of the duct to suppress the self-sustained tones. …

    The Proceedings of Conference of Kansai Branch 2018.93(0), 613, 2018

    J-STAGE 

  • Mean Free Path and Correction Factor for the Long Uniform Ducts of Isosceles-Triangle Cross Section  [in Japanese]

    MATUDA Namio

    … <p>In application of one dimensional diffusion theory to gas molecular flow in the steady state through long ducts of uniform cross section, diffusion coefficient 𝒟 is generally represented as</p><p><img align="middle" src="./Graphics/abst-61_539-1.jpg"/></p><p>here <i>λ</i> …

    Vacuum and Surface Science 61(8), 539-543, 2018

    J-STAGE 

  • Study on acoustic natural frequency and its mode of one dimensional sound field partitioned by perforated plate  [in Japanese]

    ISHIHARA Kunihiko , KUDO Satoru , MASUMOTO Takayuki , MORI Masaaki

    … <p>Karman vortex shedding occurs when the gas passes through the duct with tube bank of the heat exchangers, such as gas heaters and boilers. … Very high level sound in called "self-sustained tones" occurs due to the interference of the vortex and the sound field in the duct. … Then, perforated plates are installed in both sides of the duct to suppress the self-sustained tones. …

    Transactions of the JSME (in Japanese) 84(857), 17-00365-17-00365, 2018

    J-STAGE 

  • Acoustic natural frequency of one dimensional sound field partitioned by perforated plate:(Consideration due to viewpoint of acoustic natural mode)  [in Japanese]

    Ishihara Kunihiko , Kudo Satoru , Masumoto Takayuki , Mori Masaaki

    … <p>Karman vortex shedding occurs when the gas passes through the duct with tube bank of the heat exchangers, such as gas heaters and boilers. … Very high level sound in called "self-sustained tones" occurs due to the interference of the vortex and the sound field in the duct. … Then, perforated plates are installed in both sides of the duct to suppress the self-sustained tones. …

    The Proceedings of Conference of Kansai Branch 2017.92(0), 303, 2017

    J-STAGE 

  • Acoustic Natural Frequency and Its Mode of One Dimensional Sound Field Partitioned by Perforated Plate  [in Japanese]

    ISHIHARA Kunihiko , KUDO Satoru , MASUMOTO Takayuki , MORI Masaaki

    … Karman vortex shedding occurs when the gas passes through the duct with tube bank of the heat exchangers, such as gas heaters and boilers. … occurs due to the interference of the vortex and the sound field in the duct. … Then, perforated plates are installed in both sides of the duct to suppress the self-sustained tones. … However the perforated plates change the acoustic natural frequency of the sound field of the duct. …

    The Proceedings of the Dynamics & Design Conference 2017(0), 449, 2017

    J-STAGE 

  • Effect of perforated plate on acoustic natural frequency of one dimensional sound field partitioned by perforated plate  [in Japanese]

    KUDO Satoru , ISHIHARA Kunihiko

    … <p>Natural acoustic frequency of one dimensional duct partitioned by a perforated plate was clarified to come down with decreasing an aperture ratio experimentally and analytically. … This is equivalent to the getting long of the duct and the natural acoustic frequency can be considered to become low.</p> …

    The Proceedings of the Symposium on Environmental Engineering 2017.27(0), 111, 2017

    J-STAGE 

  • A Study on the Fundamental Cause of Stall Stagnation Phenomena in Surges in Compressor Systems

    Yamaguchi Nobuyuki

    … In order to clarify the situations, behaviours of infinitesimal disturbance waves superposed on a main flow were studied in a simplified one-dimensional flow model. … In the situation where both the sectional area ratio and the length ratio of the delivery flow-path to the suction duct are sufficiently large, the enhancement factors are greater in magnitude, which means occurrence of ordinary deep surges. …

    International Journal of Fluid Machinery and Systems 10(2), 119-137, 2017

    J-STAGE 

  • Acoustic radiation at opening with movable louver ANC system  [in Japanese]

    YANAGIMOTO Kensaku , WATANABE Seiji , SUZUKI Daisuke , TAKAHASHI Masayuki

    One of them, louver-ANC system which secondary noise source is set at each bottom side of the louver vane. … An opening of each movable louver vane is one-dimensional space similarly a duct. … The other one is slit-ANC system that is installed on an opening of machinery wall. …

    Transactions of the JSME (in Japanese) 82(833), 15-00441-15-00441, 2016

    J-STAGE 

  • Characteristics of Rotational Frequency Noise in a Small Centrifugal Compressor with Resonance Tube  [in Japanese]

    UEDA Kosuke , INOKUCHI Yuzo , YAMASAKI Nobuhiko , Daichi WAKAKI , Akihiro YAMAGATA

    … Here, the flow passage includes the volute and duct located downstreamof the compressor impeller. … One of the significant findings is that thenoise field of the pulsation noise in the duct is highly one-dimensional although the flow fields are highly three-dimensional. …

    Turbomachinery 43(12), 714-720, 2015

    J-STAGE 

  • Fire spread simulation of small plastics using FDS Ver. 6  [in Japanese]

    Mori Kazuhiro , Hideura Tsutomu , Shibata Yoshimaro , Okamoto Naoki , Nishiki Shinnosuke

    … Pyrolysis is considerd to solve the one-dimensional heat conductivity equation in three directions respectively. … We have executed fire spread simulations of small plastic gears with a diameter of 30 mm and 10 mm in thickness in a closed duct to evaluate the capability of FDS as a development tool. … In this report, we have investigated the combustion characteristics of an upper gear for the distance between two gears and aperture ratio of upper surface of the duct. …

    Japanese Journal of Forensic Science and Technology 20(1), 93-102, 2015

    J-STAGE 

  • Variation of Velocity Profile around an Automotive Brake Disc Arising from Ventilation Duct  [in Japanese]

    ITOH Kazuhiro , KUMAMARU Hiroshige , SHIMOGONYA Yuji

    … Three-dimensional velocity components were evaluated at 5 mm outside the disc edge by rotating X-type hot-wire probe. … An empirical one-dimensional model was suggested for evaluation of flow through air passage. …

    Journal of the Japanese Society for Experimental Mechanics 13(1), 27-34, 2013-03-28

    J-STAGE  References (16)

  • Development of a Simulation Method of Surge Transient Flow Phenomena in a Multistage Axial Flow Compressor and Duct System

    Yamaguchi Nobuyuki

    … The code is constructed on the basis of one-dimensional stage-by-stage modeling and application of fundamental equations of mass, momentum, and energy. …

    International Journal of Fluid Machinery and Systems 6(4), 189-199, 2013

    J-STAGE 

  • G100045 Fan noise analysis in acoustic duct using the reciprocity theorem  [in Japanese]

    ARATA Kazuki , UTSUNO Hideo

    … However, previous research in this field has been limited to noise reduction by changing the blade shape, and concentrated on one-dimensional analysis. … The primary focus of this paper is to analyze the fan noise in the three-dimensional acoustic space, and reduce the noise by controlling fan's phase. … When making a three-dimensional model, it is necessary to consider resonance in the radial direction in relatively large acoustic space. …

    The Proceedings of Mechanical Engineering Congress, Japan 2012(0), _G100045-1-_G100045-4, 2012

    J-STAGE 

  • The Two Fluid Model for the Analysis of Airflow in the Subway Systems  [in Japanese]

    MORII Nobuharu , Nobuharu MORII , 沼津工高専 , Numazu College of Technology

    … The two-fluid model are adopted to discrive the interaction between the moving train and the airflow in one-dimensional pictuer, and the self-consistent equations are derived. … The results of calculation are tested through the model experiments constituted by the open-ended tunnel and that with the ventilation duct. …

    Nagare 29(5), 345-352, 2010-10-25

    References (4)

  • 1117 A Stage-by-Stage Simulation Method for Surge Transient Flow Phenomena in Multistage Axial Flow Compressor-Duct Systems  [in Japanese]

    YAMAGUCHI Nobuyuki

    … This paper describes a practical method of compressor surge simulation over the transient behaviors both of the entire flow-path and the internal stages, in particular the latter on the basis of one-dimensional stage modeling and application of fundamental equations of mass, motion and energy. …

    The Proceedings of the Fluids engineering conference 2009(0), 375-376, 2009

    J-STAGE 

  • A numerical method for flow in a two-dimensional channel of large aspect ratio

    Miyashita Kazuko , Kawamura Tetuya

    … The former is obtained by solving one-dimensional equation analytically. … Coupling of two-directional main flow equations enables a long duct of large curvature to be solved using Cartesian coordinate system. … Two-dimensional flows in a long duct inclined at varying angles are performed to study the effectiveness of the present method. …

    Natural science report of the Ochanomizu University 58(2), 1-9, 2008-02

    IR 

Page Top