The Journal of the Korea Contents Association (한국콘텐츠학회논문지)

The Korea Contents Association (한국콘텐츠학회)
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The Estimation of Friction Velocity by Hydraulic Parameters Reflecting Turbulent Flow Characteristics in a Smooth Pipe Line

매끄러운 관수로 내 난류흐름특성을 반영한 수리학적 매개변수에 의한 마찰속도의 산정

  • 추태호 (부산대학교 사회환경시스템공학부) ;
  • 손종근 (부산대학교 사회환경시스템공학부) ;
  • 권용빈 (부산대학교 사회환경시스템공학부) ;
  • 안시형 (부산대학교 사회환경시스템공학부) ;
  • 윤관선 (부산대학교 사회환경시스템공학부)
  • Received : 2016.02.04
  • Accepted : 2016.04.01
  • Published : 2016.04.28
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Abstract

Grid(pipe network) design is an important element of Smart Water Grid, which essential to estimate hydraulic parameters such as the pressure, friction factor, friction velocity, head loss and energy slope. Especially, friction velocity in a grid is an important factor in conjunction with energy gradient, friction coefficient, pressure and head loss. However, accurate estimation friction head loss, friction velocity and friction factor are very difficult. The empirical friction factor is still estimated by using theory and equation which were developed one hundred years ago. Therefore, in this paper, new equation from maximum velocity and friction velocity is developed by using integration relationship between Darcy-Weisbach's friction head loss equation and Schlichting equation and regression analysis. To prove the developed equation, smooth pipe data areis used. Proposed equation shows high accuracy compared to observed data. Study results are expected to be used in stability improvements and design in a grid.

스마트워터그리드의 중요한 요소기술로써 그리드(관망)의 설계는 압력, 마찰계수, 마찰속도, 수두손실, 그리고 에너지 경사와 같은 수리학적 매개변수를 추정하는 것이 필수적이다. 특히, 그리드의 마찰속도는 에너지 경사, 마찰계수, 압력, 수두손실 등의 결합에 있어 매우 중요한 인자이다. 그러나 마찰 수두손실, 마찰속도 등 마찰인자를 정확히 산정하는 것은 매우 어려우며, 경험적 마찰 인자는 여전히 약 100년 전에 개발된 공식과 이론을 사용함으로써 산정된다. 따라서, 본 논문에서는 최대유속과 마찰속도 사이의 새로운 공식을 Darcy-Weisbach의 마찰수두 손실공식과 Schlichting 공식 사이의 적분관계 및 회귀분석을 통하여 개발하였다. 개발된 공식을 증명하기 위하여 매끄러운 관 자료가 사용되었으며 제안한 공식은 관측 자료와 비교하여 높은 정확성을 보여준다. 이 연구의 결과는 안정성 향상과 그리드 설계에 사용이 가능할 것으로 판단된다.

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