低壓型 Vortex tube의 기하학적 형상에 관한 실험연구

다국어 초록 (Multilingual Abstract)

This experimental study is to investigate the process of energy separation in a low pressure vortex tube with air as a working medium. A "vortex tube" is a device that separates an incoming gas flow into to streams, one hotter and one cooler than the inlet gas temperature. Part of the gas leaves through the orifice at the inlet side, the remaining part through the other end which includes any various of throttle valve to adjust the mass flow ratio of both flows.
Experimental data of the temperature of the cold and hot air leaving the vortex tube are presented. The variation of the maximum wall temperature along the inner surface of the vortex tube and the temperature distribution in the vortex tube provides useful information about the location of the stagnation P_(o)int of the flow field at the axis of the vortex tube. As temperature difference between inlet air and outlet hot air is larger, the effect of energy separation is better
The aim of this investigation is to provide fundamental data of geometric condition which improve the effect of the energy separation. In this investigation, the inner diameter of vortex tube is 20mm and the ratio of length to inner diameter is 20. The varying inlet air pressure(P_(o)) is 0.4～1.6kgf/㎠ and the cold air flow ratio(y_(c)) is 0.1～0.9. Now knowing the measurements, the experiment is carried out.
From the experiment, following conclusive remarks can be proP_(o)sed.
1) When the nozzle area ratio(Sn) was 0.142, the maximum hot air temperature difference(ΔT_(h,max)) was obtained. When Sn was 0.164, the maximum cold air temperature difference(ΔT_(c,max)) was obtained.
2) The maximum wall temperature difference(ΔTw,max) along with the inner surface of the vortex tube if provided useful information about the location of where the stagnation P_(o)int is and the flow field is at the axis of the vortex tube.
3) When the length of vortex tube was L=14D, ΔT_(h,max) and ΔTw,max were better.
4) As the inner surface roughness of the steel vortex tube was decreased, the effectiveness of the energy separation was increased about 20%.
5) When the cone angle of throttle valve was 60°, the effectiveness of the energy separation was better.
6) With adopting the sleeve ΔT_(h,max) and ΔTw,max were increased about 10% in a low pressure vortex tube at y_(c)=0.9.
7) When the ratio of the diameter of a cold end orifice(ζ) was 0.7, ΔT_(c,max) was obtained at y_(c)=0.9.

국문 초록 (Abstract)

본 논문은 저압형 vortex tube의 노즐면적비, tube 길이, 재질 및 내면 조도, throttle valve의 형상, sleeve, 저온 출구 오리피스 직경에 따른 영향에 대해 실험한 논문입니다.

목차 (Table of Contents)

• 목차
• Nomenclature = ⅲ
• List of Figures = ⅶ
• List of Tables = ⅸ
• List of Photographs = ⅸ
• 제 Ⅰ장 서론 = 1
• 1-1 연구의 필요성 = 1
• 1-2 연구동향 = 4
• 1-3 연구의 목적 = 8
• 제 Ⅱ장 이론적 고찰 = 10
• 2-1 Vortex tube의 개요 = 10
• 2-2 Vortex tube의 에너지 분리현상 = 13
• 2-3 Vortex tube의 특성에 관한 이론적 배경 = 16
• 2-4 Vortex tube의 기하학적 형상 = 22
• 제 Ⅲ장 실험장치 및 실험방법 = 26
• 3-1 저압형 vortex tube의 기하학적 형상에 따른 에너지분리 특성 실험 = 26
• 3-1-1 실험장치 = 26
• 3-1-2 실험방법 = 31
• 제 Ⅳ장 실험결과 및 고찰 = 37
• 4-1 저압형 vortex tube의 기하학적 형상에 따른 에너지분리 특성 = 37
• 4-1-1 노즐면적비에 따른 영향 = 37
• 4-1-2 저압형 vortex tube 내 온도분포 = 43
• 4-1-3 Tube 길이에 따른 영향 = 47
• 4-1-4 Tube 재질 및 내면조도에 따른 영향 = 49
• 4-1-5 Throttle valve의 형상에 따른 영향 = 52
• 4-1-6 Sleeve에 따른 영향 = 56
• 4-1-7 저온출구 오리피스 직경에 따른 영향 = 58
• 제 Ⅴ장 결론 = 60
• 참고문헌 = 61
• ABSTRACT = 66