Attainable superheat of ethane-methane solutions
V.G. Baidakov and A.S. Pankov
Institute of Thermophysics UB RAS, Ekaterinburg, Russia
Keywords: ethane-methane solution, nucleation, homogenous nucleation, heterogeneous nucleation, attainable superheating
Abstract
Мethods of measuring lifetime and continuous pressure decrease were used to study kinetics of spontaneous boiling-up of superheated ethane-methane solutions. The attainable superheats of solutions at two pressure values (1.0 and 1.6 MPa) and two concentrations of methane (2.1 and 6.0 mole %) were determined experimentally in the range of nucleation rate J = 1∙104–3∙108 s–1m–3. At temperatures 266.5, 270.0, and 273.15 K, the attainable stretching of the studied solutions was measured. The experimental results were compared with the theory of homogeneous nucleation. At nucleation rates J ≥ 2.5∙106 s–1m–3, there is a fair agreement of the theory and experiment. The discrepancy in attainable superheat temperatures Tn does not exceed 0.8 K. It is shown that significant underheating of solution to theoretical values Tn at J < 2.5∙106 s–1m–3 cannot be bound only with heterogeneous nucleation but is conditioned by other factors as well.
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