Experimental results of maximum transition boiling temperature during upflow in a circular tube at medium pressure

Abstract

Temperature-controlled measurements of forced convective boiling heat transfer during upflow of water in a vertically mounted short circular tube were performed between saturation and 400°C wall temperature. From these experimental results, 343 data points of the maximum transition boiling temperature, which corresponds to the minimum heat flux condition, were deduced. The parametric effects of pressure (range 0.11–1.2 MPa), local quality (−0.04–0.8), mass flux [10−1000 kg/(m 2·s)], and inlet subcolling (5–57 K) as comprised in these data are discussed. The present data are compared with experimental data and correlations of the true quench temperature available from the literature. Extrapolating the data to zero flow and comparing the resultant pseudodata with pertinent theories and experimental data for the minimum film boiling temperature reveals fair agreement over the entire pressure range with recent data by Sakurai et al, only.