Experimental examination of vortex-sound generation in an organ pipe: A proposal of jet vortex-layer formation model

2012 ◽  
Vol 331 (11) ◽  
pp. 2558-2577 ◽  
Author(s):  
Shigeru Yoshikawa ◽  
Hiromi Tashiro ◽  
Yumiko Sakamoto
Keyword(s):  
Sound Generation ◽  
Layer Formation ◽  
Formation Model ◽  
Experimental Examination ◽  
Vortex Sound ◽  
Vortex Layer ◽  
Organ Pipe

scholarly journals Vortices on Sound Generation and Dissipation in Musical Flue Instruments

2020 ◽  
Author(s):  
Shigeru Yoshikawa
Keyword(s):  
Acoustic Energy ◽  
Layer Model ◽  
Pipe Organ ◽  
Discrete Vortex ◽  
Vortex Sound ◽  
Vortex Model ◽  
Vortex Layer ◽  
Sound Theory ◽  
Drive Model ◽  
Discrete Vortex Model

Musical flue instruments such as the pipe organ and flute mainly consist of the acoustic pipe resonance and the jet impinging against the pipe edge. The edge tone is used to be considered as the energy source coupling to the pipe resonance. However, jet-drive models describing the complex jet/pipe interaction were proposed in the late 1960s. Such models were more developed and then improved to the discrete-vortex model and vortex-layer model by introducing fluid-dynamical viewpoint, particularly vortex sound theory on acoustic energy generation and dissipation. Generally, the discrete-vortex model is well applied to thick jets, while the jet-drive model and the vortex-layer model are valid to thin jets used in most flue instruments. The acoustically induced vortex (acoustic vortex) is observed near the amplitude saturation with the aid of flow visualization and is regarded as the final sound dissipation agent. On the other hand, vortex layers consisting of very small vortices along both sides of the jet are visualized by the phase-locked PIV and considered to generate the acceleration unbalance between both vortex layers that induces the jet wavy motion coupled with the pipe resonance. Vortices from the jet visualized by direct numerical simulations are briefly discussed.

Filtration studies of polymer solution applied in flow deviation technologies in Kazakhstan fields

2020 ◽  
pp. 27-30
Author(s):  
A.S. Strekov ◽  
◽  
B.N. Koilybaev ◽  
Keyword(s):  
Polymer Solution ◽  
Laboratory Experiments ◽  
Low Permeability ◽  
Layer Formation ◽  
Formation Model ◽  
High Permeability ◽  
Permeability Ratio ◽  
Polymer Systems ◽  
Flow Deviation

The paper deals with the results of laboratory experiments on filtration characteristics of cross-linked polymer systems (CPS) based on the “FP-307” PAA polymer solution and A grade crosslinker of acetate-chrome applied in flow deviation technologies. The studies on the estimation of CPS filtration characteristics have been carried out on the linear two-layer formation model with different interlayer permeability. Obtained results justified that the higher is formation homogeneity (permeability ratio of high permeability and low permeability interlayers), the more CPS enter into the high permeability interlayer. As a result of formation of flow deviation screen in high permeability interlayers, a regulation possibility of filtration flows direction and logging into the operation of low-permeable interlayers appears.

scholarly journals SIMULATION OF VORTEX SOUND USING THE VISCOUS/ACOUSTIC SPLITTING APPROACH

2011 ◽  
Vol 35 (1) ◽  
pp. 39-56
Author(s):  
Ting H. Zheng ◽  
Shiu K. Tang ◽  
Wen Z. Shen
Keyword(s):  
Flow Field ◽  
Flow Structure ◽  
Incompressible Flow ◽  
Analytical Solutions ◽  
Numerical Approach ◽  
Sound Generation ◽  
Vortex Sound ◽  
Acoustic Interaction ◽  
Unsteady Interaction ◽  
Good Agreement

A numerical viscous/acoustic splitting approach for the calculation of an acoustic field is applied to study the sound generation by a pair of spinning vortices and by the unsteady interaction between an inviscid vortex and a finite length flexible boundary. Based on the unsteady hydrodynamic information from the known incompressible flow field, the perturbed compressible acoustic terms are calculated and compared with analytical solutions. Results suggest that the present numerical approach produces results which are in good agreement with the analytical solutions. The present investigation verifies the applicability of the viscous/acoustic approach to flow structure-acoustic interaction.

Neural network approximation of resistivity tool responses in three–layer formation model

2020 ◽  
Author(s):  
Dmitry Yu. Kushnir ◽  
◽  
Nikolay N. Velker ◽  
Darya V. Andornaya ◽  
◽  
...  
Keyword(s):  
Neural Network ◽  
Neural Networks ◽  
Measurement Error ◽  
Approximation Method ◽  
Relative Position ◽  
Function Approximation ◽  
Model Parameters ◽  
Layer Formation ◽  
Formation Model ◽  
Test Database

We apply neural networks function approximation method to the problem of resistivity data modeling on the example of a three–layer geoelectric formation model. The model parameters distribution of the training database depends on the relative position of the tool coils and the layer boundaries. It is obtained on a test database that the signals calculated using neural networks coincide with the synthetic ones within one measurement error for more than 99.9% of the test samples.

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