Study on two-phase pressure drop of LNG during flow boiling in a 8Â mm horizontal smooth tube

Two-phase pressure drop of LNG (liquefied natural gas) during flow boiling has been measured in a horizontal smooth tube with an inner diameter of 8 mm at 0.3-0.7 MPa. And the experiments was conducted with the mass flux of 50-200 kg m−2 s−1, heat flux of 8-32 kW m−2, and vapor quality of 0.16-0.83. The effects of vapor quality, heat flux and mass flux, inlet pressure on the frictional pressure drop of LNG are discussed. The comparisons of the experimental data with the predicted value by existing six correlations are analyzed. Müller-Steinhagen and Heck [8] and Friedel [21] can provide acceptable predictions for two-phase pressure drop of LNG at inlet pressure of 0.3-0.7 MPa among them.