• 제목/요약/키워드: Three Dimensional Sound Field

검색결과 33건 처리시간 0.027초

3차원 라우드스피커 어레이를 이용한 음장재현기술 (Sound Field Reconstruction Technology Using a Three Dimensional Loudspeaker Array)

  • 서정일;강경옥
    • 한국음향학회지
    • /
    • 제28권8호
    • /
    • pp.723-731
    • /
    • 2009
  • 본 논문에서는 3차원 라우드스피커 어레이를 이용하여 다수의 청취자에게 동일하게 실감 있는 음장을 제공하기 위한 음장 재현 알고리즘을 제안한다. 제안된 알고리즘은 제어하고자 하는 3차원 공간 영역을 정의하고, 정의된 영역에서 원음장과 라우드스피커 어레이를 이용하여 재현되는 음장간의 자승오차가 최소가 되도록 라우드스피커 구동신호를 제어하는데 기초한다. 제안된 알고리즘의 성능을 검증하기 위하여 40개의 라우드스피커를 이용한 구형 3차원 어레이를 구성하였으며, 이를 이용한 실험결과와 고찰결과를 제시한다.

소리의 공간 제어를 위한 구형 다채널 스피커 어레이 설계 (Design of Multichannel Spherical Loudspeaker Array for the Spatial Sound Manipulation)

  • 강동수;최정우;이정민;김양한
    • 한국음향학회지
    • /
    • 제31권4호
    • /
    • pp.214-224
    • /
    • 2012
  • The objective of this paper is to design multichannel spherical loudspeaker array by considering various positioning methods such as Gaussian grid, Lebedev grid and packing method. For the spatial sound manipulation, which is to make desired sound field by controling multiple sound sources, the Kirchhoff-Helmholtz integral states that sound fields can be reproduced in terms of infinite control sources on the integral surface. But since we cannot control infinite number of sources for the implementation, we have to allocate finite number of sound sources which can approximately act as infinite number of sources. To manipulate sound field inside of a sphere (which is typical example of three dimensional array) by controlling sound sources on the surface, three methods of allocating sound sources, which are Gaussian grid, Lebedev grid and packing method, are reviewed. For each geometry, the performances of manipulation rendered by time-reversal operator and higher-order ambisonics are compared.

소리를 시각화하는 다양한 방법 (Sound Visualization Gallery: A means to express sound field in space and time)

  • 최정우;김양한
    • 한국소음진동공학회:학술대회논문집
    • /
    • 한국소음진동공학회 2005년도 추계학술대회논문집
    • /
    • pp.629-632
    • /
    • 2005
  • What does sound look like if we can see it? It might depend on the acoustic variables we want to see. In this article, we propose various ways to visualize or express sound field in much more intuitive manner. In particular, new visualization schemes that can effectively visualize sound intensity and 3D pressure field are proposed. This allows us to represent sound pressure, particle velocity and acoustic conductance at the same time, even in three-dimensional coordinate. Visualization examples corresponding to the proposed techniques show that we can successfully transfer the meaning of physical variable to visual space.

  • PDF

삼차원 와선의 비정상 거동에 의한 원거리 음압의 수치해석 (Numerical Calculation of the Far Field Acoustic Pressure from the Unsteady Motion of the Three-dimensional Vortex Filament)

  • 유기완;이덕주
    • 대한기계학회논문집A
    • /
    • 제21권6호
    • /
    • pp.942-950
    • /
    • 1997
  • Far field acoustic pressure from the evolution and interaction of three-dimensional vortex filament is calculated numerically. A vortex ring is a typical example of the three-dimensional vortex filament. An elliptic vortex ring emits a strong sound signal due to significant distortion and stretching of the vortec filament. The far field acoustic pressure is linearly dependent on the third time derivatives of the vortex positions. A numerical scheme of high resolution is employed to describe in detail the elliptic vortex ring motions which ar highly nonlinear. Descretized vortex filaments are interpolated by using a parametric blending function to remove a possible numerical instability. The distorted vortex filament, owing to the self-induced and the induced velocity from the other vortex segments, is redistributed at each time step. The accuracy and efficiency of the scheme are validated by comparisons with the analytic solution of circular vortex ring interaction.

2차원과 3차원 아음속 공동 유동 특성에 대한 수치적 연구 (NUMERICAL ANALYSIS OF TWO- AND THREE-DIMENSIONAL SUBSONIC TURBULENT CAVITY FLOWS)

  • 최홍일;김재수
    • 한국전산유체공학회:학술대회논문집
    • /
    • 한국전산유체공학회 2007년도 추계 학술대회논문집
    • /
    • pp.187-193
    • /
    • 2007
  • The flight vehicles have cavities such as wheel wells and bomb bays. The flow around a cavity is characterized as unsteady flow because of the formation and dissipation of vortices due to the interaction between the freestream shear layer and cavity internal flow, the generation of shock and expansion waves. Resonance phenomena can damage the structures around the cavity and negatively affect aerodynamic performance and stability. In the present study, numerical analysis was performed for cavity flows by the unsteady compressible three dimensional Reynolds-Averaged Navier-Stokes (RANS) equations with Wilcox's ${\kappa}\;-\;{\omega}$ turbulence model. The cavity has the aspect ratios of 2.5, 3.5 and 4.5 for two-dimensional case, same aspect ratios with the W/D ratio of 2 for three-dimensional case. The Mach and Reynolds numbers are 0.53 and 1,600,000 respectively. The flow field is observed to oscillate in the "shear layer mode" with a feedback mechanism. Based on the SPL(Sound Pressure Level) analysis of the pressure variation at the cavity trailing edge, the dominant frequency was analyzed and compared with the results of Rossiter's formula. The MPI(Message Passing Interface) parallelized code was used for calculations by PC-cluster.

  • PDF

3차원 고세장비 공동 주위의 난류유동 및 음향 특성에 관한 수치적 연구 (NUMERICAL ANALYSIS FOR TURBULENT FLOW AND AERO-ACOUSTIC OVER A THREE DIMENSIONAL CAVITY WITH LARGE ASPECT RATIO)

  • 문바울;김재수
    • 한국전산유체공학회:학술대회논문집
    • /
    • 한국전산유체공학회 2008년도 학술대회
    • /
    • pp.297-301
    • /
    • 2008
  • The flight vehicles have cavities such as wheel wells and bomb bays. The flow around a cavity is characterized as unsteady flow because of the formation and dissipation of vortices due to the interaction between the freestream shear layer and cavity internal flow, the generation of shock and expansion waves. Resonance phenomena can damage the structures around the cavity and negatively affect aerodynamic performance and stability. The flow field is observed to oscillate in the "shear layer mode" with low aspect ratio. In the present study, numerical analysis was performed for cavity flows by the unsteady compressible three dimensional Reynolds-Averaged Navier-Stokes (RANS) equations with Wilcox's $\kappa$-$\omega$ turbulence model. The flow field is observed to oscillate in the shear layer mode" with large aspect ratio. Based on the SPL(Sound Pressure Level) analysis of the pressure variation at the cavity trailing edge, the dominant frequency was analyzed and compared with the results of Rossiter's formul. The aero-acoustic wave analyzed with CPD(Correlation of Pressure Distribution).

  • PDF

3차원 고세장비 공동 주위의 난류유동 및 음향 특성에 관한 수치적 연구 (NUMERICAL ANALYSIS FOR TURBULENT FLOW AND AERO-ACOUSTIC OVER A THREE DIMENSIONAL CAVITY WITH LARGE ASPECT RATIO)

  • 문바울;김재수
    • 한국전산유체공학회:학술대회논문집
    • /
    • 한국전산유체공학회 2008년 추계학술대회논문집
    • /
    • pp.297-301
    • /
    • 2008
  • The flight vehicles have cavities such as wheel wells and bomb bays. The flow around a cavity is characterized as unsteady flow because of the formation and dissipation of vortices due to the interaction between the freestream shear layer and cavity internal flow, the generation of shock and expansion waves. Resonance phenomena can damage the structures around the cavity and negatively affect aerodynamic performance and stability. The flow field is observed to oscillate in the "shear layer mode" with low aspect ratio. In the present study, numerical analysis was performed for cavity flows by the unsteady compressible three dimensional Reynolds-Averaged Navier-Stokes (RANS) equations with Wilcox's ${\kappa}-{\varepsilon}$ turbulence model. The flow field is observed to oscillate in the "shear layer mode" with large aspect ratio. Based on the SPL(Sound Pressure Level) analysis of the pressure variation at the cavity trailing edge, the dominant frequency was analyzed and compared with the results of Rossiter's formul. The aero-acoustic wave analyzed with CPD(Correlation of Pressure Distribution).

  • PDF

가상 현실 선박 조종 시뮬레이터 구현을 위한 3차원 음장생성(I) : 머리전달함수 모델링 (3-D Sound-Field Creation Implementing the Virtual Reality Ship Handling Simulator(I): HRTF Modeling)

  • 임정빈
    • 한국항해학회지
    • /
    • 제22권3호
    • /
    • pp.17-25
    • /
    • 1998
  • This paper describes elemental technologies for the creation of three-dimensional(3-D) sound-field to implement the next-generation Ship Handling Simulator with human -computer interaction, known as Virtual Reality. In the virtual reality system, Head-Related Transfer Functions(HRTF's) are used to generate 3-D sound environmental context. Where, the HRTF's are impulse response characterizing the acoustical transformation in a space. This work is divided into two parts, the part Ⅰis mainly for the model constructions of the HRTF's, the part Ⅱis for the control of 3-D sound-field by using the HRTF's . In this paper, as first part, we search for the theory to formulate models of the HRTF's which reduce the dimensionalityof the formulation without loss of any directional information . Using model HRTF's we report results from psychophysical tests used to asses the validity of the proposed modleing method.

  • PDF

2차원적 음원추적에 관한 연구 II (A Study on 2-Dimensional Sound Source Tracking System II)

  • 문성배;전승환
    • 한국항해학회지
    • /
    • 제22권4호
    • /
    • pp.31-36
    • /
    • 1998
  • The whistle is a very important information source for the safety navigation under foggy weather. But navigator has no concern about this, because it must be achived by human hearing sense and considered as a vague signal. If the range and relative bearing of signal source can be detected automatically, it would be very useful system for preventing marine casualties making a lot of economic loss and environment pollution. Before the algorithm of 2-dimensional sound source tracking system was reported. This paper describes the method that can obtain the time lag between three signals and the theory of cross-correlation analysis and subtraction method for cauculating the time lag by using the digital signal data sequences. And a series of experiments were carried out for various position of sound source in the range from 200cm to 530cm. As a result, we have recognized that sound source tracking system is possible to the sea field with improvement of position error.

  • PDF

입체음장재현을 위한 멀티채널시스템 (A Multichannel System for Virtual 3-D Sound Rendering)

  • 이찬주;박영진;오시환;김윤선
    • 한국음향학회:학술대회논문집
    • /
    • 한국음향학회 2000년도 하계학술발표대회 논문집 제19권 1호
    • /
    • pp.223-226
    • /
    • 2000
  • Currently a multichannel system for virtual 3-D sound rendering is under development. Robust sound image formation and smooth real time interactivity are main design Points. The system utilizes VBAP algorithm as virtual sound image positioning. Overall system settings can be easily configured. We developed software, RIMA. as a driving Program of the system. At this stage, it is possible to position virtual sound images at arbitrary positions in three-dimensional space. The characteristics of the system are discussed. The system has been applied to the KAIST Bicycle Simulator to generate the virtual sound field.

  • PDF