Effects of Condensate Inundation and Vapor Shear on Shell-Side Condensation

Abstract

본 연구에서는 shell측 응축에 미치는 응축액의 inundation과 증기 전단의 영향을 복합적으로 상관시키는 여러 가지 모델으 다루었다. 공업적 규모의 다관형 응축기에서 얻은 탄화수소 혼함물의 응축 실험데이터에 대한 수치모사르 수행하여 이러한 모델들을 평가하였다. 단일상의 응축액에 비해 응축액막의 열전달계수르 추산하는 것이 어려운 2상의 응축액을 형성하는 경우도 검토하였다. 응축액의 inundation과 증기의 전단이 응축현상에 대한 이론적 예측에 증요한 영향을 주는 것을 알 수 있었도, 증기의 전단에 대한 수정된 Shekriladze방법에 Nusselt의 inundation모들을 결합한 경우에 가장 좋은 예측을 얻을 수 있었다. 본 연구에서는 Nusselt의 inundation모델이 응축액막의 열전달계수를 약 40% 정도 감소시키고, 증기의 전단은 25%까지 열전달계수를 증가시키는 것으로 나타났다.

The present work descriges various models with respect to the manner of allowing for the combined influence of condensate inundation and vapor shear on shell-side condensation. These models have been evaluated by simulating extensive data on condensation in a shell and tube condenser of industrial scale and design. The study includes condensation of vapors forming two-phase condensate, in which the method of predicting condensate film coefficient is more uncertain than that available for single phase condensates. In has been concluded for the data of the present work that condensate inundation and vapor shear affect the theoretical predictions of condensation significantly, and the vest prediction was obtained when the combined coefficient obtained by the modified Shekriladze method the vapor shear is corrected for inundation by the method of Nusselt. Nusselt's correction may reduce the condensate film coefficient by 40%, while vapor shear enhances the coefficient by up to 25% for the systems considered here.

The present work descriges various models with respect to the manner of allowing for the combined influence of condensate inundation and vapor shear on shell-side condensation. These models have been evaluated by simulating extensive data on condensation in a shell and tube condenser of industrial scale and design. The study includes condensation of vapors forming two-phase condensate, in which the method of predicting condensate film coefficient is more uncertain than that available for single phase condensates. In has been concluded for the data of the present work that condensate inundation and vapor shear affect the theoretical predictions of condensation significantly, and the vest prediction was obtained when the combined coefficient obtained by the modified Shekriladze method the vapor shear is corrected for inundation by the method of Nusselt. Nusselt's correction may reduce the condensate film coefficient by 40%, while vapor shear enhances the coefficient by up to 25% for the systems considered here.