Heat transfer correlations of rifled tubing for boilers under sliding pressure operating condition.

Experimental study on heat transfer to the supercritical water upward flow in a vertical tube with internal helical ribs

“…Here the present experimental data are marked by solid points and the data of other researchers by hollow points. The data of Iwabuchi [25,26] and Wang [31] were excluded from consideration due to their lack, and because their test parameters rather differed from those for the current experiment.…”

“…The HTC values at SCW up-flow in ribbed tubes of other type also presented in Fig. 8 were calculated on the basis of correlations given in [26,[29][30][31][32][33]. These investigations were carried out at the same parameters as during the current test.…”

“…Iwabuchi [26] Nuw a smooth tube. Outside the scope of the LSHR region the wall temperature increases greatly with the bulk fluid enthalpy, but the HTC value changes a little.…”

“…The heat transfer to supercritical water (SCW) flow in ribbed tubes with specific tube structures was experimentally investigated separately [24][25][26][27][28][29][30][31][32][33], as listed in Table 1.…”

“…The modified Dittus-Boelter equation was used by Iwabuchi [26] and Griem [27] to develop the HTC correlations in ribbed tubes for SCW flow, see Table 2. The Griem correlation was developed for two pressure ranges taking into account the selected specific heat C p,sel .…”