| Title |
Analysis of Geometrical Effects on Heat Transfer Characteristicsin a Modular Flat Tube-Bundle Heat Exchanger |
| Keywords |
Heat exchanger ; 열교환기 ; Flat tube-bundle ; 편평원관군 ; Numerical analysis ; 수치해석 ; Aspect ratio ; 종횡비 |
| Abstract |
Flow channels with non-circular cross-sections are encountered in a wide va-riety of heat exchangers. Accurate friction factor and Colburnj factor data are essential for the design and viable applications of such heat exchangers. In this study, an analysis is con-ducted on heat transfer and pressure drop characteristics for tube-bundle heat exchanger with various arrangements of tubes, of which their geometry could easily be modified from a cir-cular one in a harsh environment. The parameters investigated are aspect ratio, pitch, and in-clined angle of tubes. The results obtained are:(1) Aspect ratio has larger influence on thej andf factor than pitch;(2) As aspect ratio increases, bothj andf factors decrease;(3) The high performance is achieved when the pitch and aspect ratio are in the range of 1.5∼2.5 and 1.25∼2.0, respectively; and(4) the inclined arrangements of tubes show unfavorable results for both heat transfer and pressure drop characteristics in spite of the positive possibility of condensate removals in a latent heat recovery system. |