Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
권호 표지
DOI QR코드

DOI QR Code

Error Characteristics of Clamp-on Ultrasonic Flowmeters Depending on Location of Sensors and Downstream Straight Run of Bent Pipe

곡관후단의 직관거리와 센서위치에 따른 초음파유량계의 오차특성

  • Received : 2011.03.28
  • Accepted : 2011.05.17
  • Published : 2011.08.01
Download PDF
⟨ Previous Next ⟩

Abstract

Flowmeters that measure the amount of fluid passing through conduits must kept accurate by comparison and the periodic calibration. The reference meters used are clamp-on meters that mount sensors on the outer wall of the pipe. They are called 1-path, 2-path or 4-path flowmeters depending on the number of sensors. We selected a flowmeter mainly used for K-water as test a flowmeter. We carried out experiments to find the intrinsic error of the flowmeter and errors in the downstream of a double bent pipe. The results show that there are the sensor locations that meet the tolerance. We suggested the angle of the sensor, the straight run from the downstream of the bent pipe and the number of sensors. So it is possible to improve the water treatment process and increase the accounted water rate by upgraded flow measurement technology.

관로를 통과하는 유체의 양을 측정하기 위해 설치된 유량계는 주기적인 교정과 비교측정을 통하여 측정의 정확도와 신뢰성을 확보하고 있다. 이때 사용되는 기준기는 휴대용 즉 센서가 관로의 외벽에 부착되는 건식 초음파유량계이며 사용되는 측정센서의 수량에 따라 1회선, 2회선, 4회선으로 구분된다. 본 연구의 대상은 K-water에서 주로 사용하고 있는 유량계를 선정한 후 직관거리가 충분히 확보된 상태에서 실험대상 유량계가 갖는 고유오차와 유동교란인자인 2중 곡관 후단에서의 직관거리별 오차에 대한 특성실험을 실시하였다. 실험결과를 기준으로 허용오차를 만족하는 센서위치 즉, 관로외부에 부착하는 각도와 곡관 후단으로부터의 이격거리 및 최적의 회선수를 제시하여 유량측정기술 향상을 통한 수처리 공정관리 및 유수율 제고기반을 마련하였다.

Keywords

References

  1. Hwang, S. Y., Seo, J. S. and Park, J. K., 2007, "Uncertainty Evaluation of Ultrasonic Flowmeter Varied with Temperature and New Improvement Method," Proceeding of the KFMA Annual Meeting, pp. 503-508.
  2. Som, J. N., 1994, "Study on the Calibration of the Transit-time Ultrasonic Flowmeter," Jour Pure Appl. Ultrason, 17, pp. 114-120.
  3. Lee, H. J., Hwang, S. Y. and Kim, K. J., 2004, "Flowrate Integration Errors of Multi-path Ultrasonic Flowmeter using Weighting Factors," Journal of KFMA, Vol. 7, No. 5, pp. 7-12. https://doi.org/10.5293/KFMA.2004.7.5.007
  4. KS B ISO/TR 12765, 2005, "Measurement of Fluid Flow in Closed Conduits - Methods Using Transit-time Ultrasonic Flowmeters."
  5. JEMIS-032, 1987, "Method of Flow Measurement by Ultrasonic Flowmeters."
  6. Lee, D. K. and Park, J. H., 2008, "A Study on Error Characteristics of Large Size Electromagnetic Flowmeter in the Range of Low Velocity," Journal of KFME(B), Vol. 32, No. 3, pp. 235-240 https://doi.org/10.3795/KSME-B.2008.32.3.235
  7. Lee, D. K. and Park, J. H., 2008, "Uncertainty Characteristics of Diverter for Flowmeter Calibration System," Journal of KFMA, Vol. 11, No. 3, pp. 50-55. https://doi.org/10.5293/KFMA.2008.11.3.050
  8. Lim, K. W., 2001, "A Study on the Measurement Uncertainty of Flowmeter Calibrator," Journal of KSME(B), Vol. 25, No. 4, pp. 561-571.
  9. Lim, K. W., Choi, Y. M., Lee, K. B., Oh, Y. K. and Yoon, B. R., 2007, "Development of Design and Uncertainty Estimation Technique of High Flowrate Flowmeter Calibration," KRISS/IR-2007-087, KRISS, pp. 46-51.
  10. ISO 4185, 1980, "Measurement of Liquid Flow in Closed Conduits - Weighing Method."

Cited by

  1. Correlation Analysis of Flow Characteristics Downstream of a Double Bent Pipe and Mounting Positions of Ultrasonic Flowmeter vol.37, pp.11, 2013, https://doi.org/10.3795/KSME-B.2013.37.11.1037
  2. Characteristics of Multipath Ultrasonic Flowmeter Installed Upstream and Downstream of Flow Disturbance Factors-Contraction, Expansion, and Tee Pipe vol.36, pp.8, 2012, https://doi.org/10.3795/KSME-B.2012.36.8.877