Nucleate pool boiling in ethane was studied at 0.15

0.2 and 0.3 MPa at heat flux between 14.27 and 81.22 kW·m-2 by visualization technique. Images of departure ethane bubbles at upper smooth surface of the vertical 20 mm-diameter heating copper rod were recorded at a frame rate of 2619 fps and a full resolution of 960×720 pixels by Phantom high-speed digital camera. The departure bubble diameters were got by image processing and analyzed relationship with Jacob number(Ja). With the increase in Ja

bubble departure diameter tended to increase but not monotonically. Compared experimental diameter data with predictions of six most used correlations

it was found that Kim and Kim(2006) model had the best prediction with absolute average deviation (AAD) below 30% at all three pressures and 50% of the predicted values within 30%-40% deviations at 0.15 MPa. Finally

a new correlation was proposed on a basis of fitting bubble departure data and Kim and Kim (2006) power law model

which has within ±30% difference between prediction and experimental data. The prediction for methane departure diameters at four different pressures were within ±30% (only one over ±30%) of the literature data. The new correlation works well for both methane and ethane at various operating conditions

however

its application range is limited because the correlation is obtained from data under low Ja.