Flow patterns, heat transfer and pressure drop for evaporation and condensation of R134A in microfin tubes

An Empirical Model to Predict the Transition Between Stratified and Nonstratified Gas–Liquid Two-Phase Flow in Horizontal and Downward Inclined Pipes

“…The accuracy of the proposed model is compared against the models of Taitel and Dukler [13] and Cheng et al [16] using data tabulated in Table 2 [1,2,3,4,5,6,19,[21][22][23][24][25][26][27]. The correlation of reference 13 is used for comparison against all data considered in this study, while the model of reference 16 is used only for horizontal two-phase flow data (since it is developed and recommended to be used for horizontal two-phase flow).…”

“…Air-water 0, -5, -10, -20, -30, -45, -60, -75 998 1 Andritsos [23] 95.3 Air-water 0 998 1 Jepson et al [24] 300 Air-water 0 998 1 Nguyen [1] 45.5 Air-water 0, -7, -20, -45, -67 998 1 Shoham [2] 25.4 Air-water 0, -10, -30, -50, -70 998 1 Ping et al [25] 50.4 Air-oil 0 856 63 Kang et al [6] 101 Air-oil -15, -30 ≈ 910 2.5 Kokal and Stanislav [5] 25.4 Air-oil -1, -5, -9 860 7 Meng et al [26] 50.1 Air-oil 0, -1, -2 875 5.6 Colombo et al [22] 8.9 R-134a 0 1278 0.25 Crawford et al [3] 25.4 R-113 -15, -30, -45, -60 1379 0.28 Quiben and Thome [21] 13.8 R22/R-410A 0 1265/1150 0.21/0.15 Thome and Hajal [19] 12 R-134a 0 1260 0.23 Gibson [4] 50.1 A i r -K 2 CO 3 -2, -7 1420 3 Andritsos [23] 95.3 Air-glycerin 0 1160-1220 10-80 Mukherjee [27] 38.1 Air-kerosene -5, -20, -30, -50, -70 780-800 1.6-2 It is also of interest to check the performance of the proposed correlation against the empirical model of Cheng et al [16] for horizontal two-phase flow. As shown in Figure 7, all three correlations appear to predict stratified flow data correctly.…”

Forced convective heat transfer and flow characteristics of ionic liquid as a new heat transfer fluid inside smooth and microfin tubes

“…The microfin tube was first developed by Fujie et al of Hitachi Cable [8]. Since then, many experimental and theoretical investigations had been extensively performed for convective condensation and boiling heat transfer in microfin tubes [9][10][11][12][13][14], and the phase change heat transfer enhancement mechanisms were presented. Compared to phase change heat transfer, experimental investigations of single phase heat transfer characteristics in microfin tubes are less reported.…”

Comparison of tubeside condensation and evaporation characteristics of smooth and enhanced heat transfer 1EHT tubes

“…Thome et al [12] proposed the development of simplified flow structures in various flow regimes. Colombo et al [13] presented heat transfer data and flow patterns for smooth and microfin tubes for evaporation and condensation conditions. Heat transfer coefficient and pressure drop of various microfin tubes (various fin numbers) are summarized.…”