The operational characteristics of a VCHP in the various operation conditions were investigated. A water heat pipe including nitrogen gas as a non-condensable gas was designed and manufactured using a copper tube with 12.7㎜ diameter and 480㎜ length. Experimental data showed that the length of non-active zone mostly depend on the temperature of the vapor and the non-condensable gas. And the heat flow rate was negligible parameter at the same vapor temperature in the range of the experiment. As the vapor temperature increase and the non-condensable gas temperature decrease, the non active zone was increased. The calculated data by using the flat front model and the experimental results showed same tendency.

Abstract
 1. 서론
 2. VCHP의 작동 영역
 3. 실험장치 및 실험 방법
 4. 실험 결과 및 고찰
 5. 결론
 참고문헌

• 강환국(동은에이티에스) | H. K. KANG
• 조운(용인송담대학 자동차기계과) | W. CHO