• Title/Summary/Keyword: 비틀림 테이프

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A Study on the Performance of a Shell Tube Heat- Exchanger with Twisted Tape (비틀림 테이프에 의한 이중관형 열교환기의 성능에 관한 연구)

  • Kim, Doo-Chun;Kim, Chul-Han
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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    • v.11 no.2
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    • pp.1-9
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    • 1982
  • Friction losses and heat transfer characteristics were studied experimentally for fully developed tubulent flow in tubes with twisted tape swirl generators. Data were obtained for pitch- to-diameter ratios from 8.10 to 25.71 with water under forced convection cool ins conditions. The experimental results of this and that of previous swirl flow investigation by Smithberg and Landis were compared. Nusselt number and friction data are combined in a constant pumping power comparision for swirl and straight flow, which indicates that improvement of 2.0 times in the best performance can be obtained with twisted tape-insert tube. A twisted tape-insert tube is recommended in the case of low temperature difference in heat-exchanger.

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An Experimental Study on Heat Transfer Characteristics of Arrangement Chips by Swirl Jet Impingement (선회충돌제트에 의한 배열 칩의 열전달 특성에 관한 실험적 연구)

  • 최재욱;전영우;정인기;박시우
    • Journal of Advanced Marine Engineering and Technology
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    • v.28 no.4
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    • pp.624-631
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    • 2004
  • The experimental study on heat transfer characteristics of protruding heated block array as conducted to investigate and to compare the performance of impinging single circular jet in fully developed tube with a twisted tape as a swirl generator. The effects of jet Reynolds number(Re=8700, 13800, 20000. 26500), dimensionless jet-to-block distance(H/d=1. 3, 5. 7) and swirl number(S=0.11, 0.23, 0.30) of the swirl jet on the average Nusselt number for each block and all blocks have been examined. Measurements of heat transfer rate on block surfaces were used naphthalene sublimation technique. Mean velocity and turbulence intensity of the jet along the axis were measured. Potential core length of the jet was 5 times of nozzle diameter because it was fully developed and initially turbulent. With the twisted tape in the nozzle, heat transfer coefficients were higher than those without the twisted tape. which are mainly caused with increasing the jet Reynolds number and swirl number.

A Case Report : Remission of Spasmodic Torticollis Confirmed with Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) And Tsui Score for Outcome Measure (사경증 평가도구를 통해 관해를 확인한 경련성 사경증 환자 1례)

  • Nam, Tong-Hyun
    • The Journal of the Society of Korean Medicine Diagnostics
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    • v.14 no.1
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    • pp.101-110
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    • 2010
  • Objective : A case of idiopathic spasmodic torticollis rapidly improved after Oriental Medical treatments and supplementary trigger point injection is reported. Methods & Results : The oriental medical treatment for spasmodic torticollis including acupuncture, bee-venum therapy, herb medication, taping therapy, chuna therapy and physical therapy was performed for pain alleviation, and trigger point steroid injections were also performed. The Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) and the Tsui Score were used for outcome measure of the spasmodic torticollis. After treatment for 15 days, the TWSTRS showed a decrease from 56 to 22.3 and the Tsui score also decreased from 13 to 5. Conclusions : We concluded that the oriental medical treatment including acupuncture, bee-venum therapy and taping therapy rapidly induced spasmodic torticollis to remission.