CAJ | 학술논문

以浸没在高位水箱中的竖直管束为研究对象，对不同热负荷条件下竖直管束内冷凝换热特性进行研究，通过对比中心管与周围旁管的凝液增长率以及冷凝换热热阻，分析了中心管与旁管换热特性的差异，解释了低压条件下冷凝换热系数剧烈下降现象。将管束冷凝试验数据与已有单管试验数据对比发现，在相同蒸汽工况下，单管的冷凝换热系数与旁管的冷凝换热系数吻合较好，但远低于中心管的冷凝换热系数，说明中心管的换热性能相对于旁管确实得到了强化。通过对比换热系数的试验值与经典努塞尔理论和努塞尔修正理论的计算值发现，中心管的试验值与努塞尔修正理论计算值吻合较好，但旁管的偏差较大。
이침몰재고위수상중적수직관속위연구대상，대불동열부하조건하수직관속내냉응환열특성진행연구，통과대비중심관여주위방관적응액증장솔이급냉응환열열조，분석료중심관여방관환열특성적차이，해석료저압조건하냉응환열계수극렬하강현상。장관속냉응시험수거여이유단관시험수거대비발현，재상동증기공황하，단관적냉응환열계수여방관적냉응환열계수문합교호，단원저우중심관적냉응환열계수，설명중심관적환열성능상대우방관학실득도료강화。통과대비환열계수적시험치여경전노새이이론화노새이수정이론적계산치발현，중심관적시험치여노새이수정이론계산치문합교호，단방관적편차교대。
This experiment is to investigate the condensation heat transfer characteristic of vertical tube bundle by controlling the steam parameters in vertical tubes immersed in head water tank .To explain the phenomenon of a sharp decline of condensation heat transfer coefficient and the difference of condensation heat transfer characteristics between center tube and side tube ,the growth rate of condensate and condensation ther‐mal resistance were analyzed detailedly .The experimental results show that the conden‐sation heat transfer coefficient of tube bundle is significant better than that of single tube ,especially the condensation heat transfer coefficient of the center tube is much bet‐ter than that of side tube under the same steam conditions .Through the contrast of heat transfer coefficient of the test value and the calculated values of both the classical and the modified Nusselt theories ,the results show that the test value of center tube accords well with the calculation value of the modified Nusselt theory ,but the deviation of side tube is larger .