Boiling Pure Fluids at Sub Atmospheric Pressures

Abstract

The study and sizing of sorption machine evaporators are based on the prediction of the heat transfer coefficient at atmospheric pressures, but in the literature we only find correlations modeled from experiments for a wide range of pressure, where the majority of the data are above atmospheric pressure; A review of the experiments of boiling at sub-atmospheric pressures was carried out and compared to four known correlations for three types of fluids, which are water, hydrocarbons and refrigerants; The results obtained showed deviations of the predicted data from the experimental values for three correlations and convincing results for the fourth.

Heat transfer coefficient correlations of water subatmospheric vaporization in a channel of a smooth plate heat exchanger, based on Vaschy-Buckingham theorem

“…[20]. Thus, Dittus-Boelter [19], Labuntsov [11], Kruzylin [11], Stephan-Abdelsalam [11], Chang (pool boiling region and intermittent region) [13], Mc Nelly [21] and Yu [20] correlations consist of parameters that influence water vaporization.…”

“…Baki [21] performed a review on experimental boiling data at subatmospheric pressures for three different fluids, among them water, to compare them to four known correlations. His results showed poor accuracy between experimental and predicted data for three of the correlations.…”

“…Pool boiling zone Mc Nelly correlation (g) Figure 5 : Comparison between experimental HTC (hexp) of pool boiling zone and HTC predicted (hpred) by correlations of: (a) Dittus-Boelter [19], (b) Labuntsov [11], (c) Kruzylin [11], (d) Stephan-Abdelsalam [11], (e) Chang [13], (f) Mc Nelly [21] and (g) Yu [20] Table 4 : Statistical comparison between the HTC experimental of pool boiling zone and the HTC predicted by the correlations in the literature.…”

“…24 7 73 0.67 Kruzylin [11] 28 − 26 54 0.64 Labuntsov [11] 69 − 69 0 0.58 Stephan-Abdelsalam [11] 77 − 77 0 0.60 Chang [13] 29 8 69 0.57 Mc Nelly [21] 57 − 57 3 0.55 Yu [20] 39 39 27 0.96 Table 4 indicates that the HTC experimental database for the pool boiling area did not accurately match the majority of the correlations considered.…”

“…(n) Figure 6 : Comparison between experimental HTC (hexp) of liquid film evaporation zone and HTC predicted (hpred) by correlations of: (h) Dittus-Boelter [19], (i) Labuntsov [11], (j) Kruzylin [11], (k) Stephan-Abdelsalam [11], (l) Chang [13], (m) Mc Nelly [21] and (n) Yu [20] [20] 31 31 45 0.97…”