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Heat Transfer Handbook part 75. The Heat Transfer Handbook provides succinct hard data, formulas, and specifications for the critical aspects of heat transfer, offering a reliable, hands-on resource for solving day-to-day issues across a variety of applications. | CONDENSATION IN SMOOTH TUBES 735 within the following ranges 80 Es KSoE D 102 a 5kg m2 s Gt 300kg m2 s 0.1 Ja 2.3 970 ReZo 11 000 0.1 xq 0.9 where the constant c and the exponents are given in Table 10.2 and h is calculated from the smooth correlation given in Section 10.6. Most of the data were correlated to within 15 . 10.6 CONDENSATION IN SMOOTH TUBES 10.6.1 Introduction Studies of condensation are numerous in the technical literature. These studies include analytical efforts to model the physics of condensation processes experimental efforts to measure the heat transfer behavior of certain fluids and various combinations of the two. Most investigators have collected data fora limited numberof fluids under a range of operating conditions that was suitable for the applications of their interest. Efforts to match their data with existing correlations or to develop correlations to fit their own data have met with some success. Many correlations that are available come with no explicit range of parameters over which they can be expected to give accurate results. Although there are handbooks and design manuals supplying reasonable recommendations for a design engineer who is searching the technical literature the overall literature provides seemingly diverse reports about which correlation is best. The differences between the lowest and highest predicted heat transfer ceefflcients in certain cases cab be as high as at faotof 2f 2 or 3 Hinde etal. 1992 . There is agreement in the literature that the mechanisms of heat transfer and pressure drop are intimately linked with the prevailing two-phase flow regime. This has led to many studies aimed at predicting what dimensionless parameters govern specific flow regime transitions and at what values of these dimensionless parameters certain transitions are expected to occur. Although debates still exist in the literature concerning differences in the flow regime predictions of various researchers a basic understanding has .
