# Table Root mean square errors

Fig. 18(a) and (b) show comparison results respectively for Chisholm’s correlation and Abdelall et al.’s one.

Fig. 18. Comparison of ΔpC between experiment and calculation by correlations in literatures. (a) Chisholm correlation (b) Abdelall et al. correlation .Figure optionsDownload full-size imageDownload as PowerPoint slide

Abdelall et al. [4] also reported that ADX 10059 their measured two-phase pressure changes due to sudden contraction indicated the occurrence of significant velocity slip between liquid and gas phases. After that, synapse applied the following slip flow model based equation to predict their data.equation(25)ΔpC=Gd2ρH1CC2-σA22ρ″2+(1-CC)ρ′equation(26)ρH=ρL1+xρLρG-1equation(27)ρ′=(1-x)2ρL(1-α)+x2ρGαequation(28)ρ″=(1-x)3ρL2(1-α)2+x3ρG2α2equation(29)α=1(1-x)ρGρLS+1Here, ρH is the homogeneous density and S is the slip ratio. As for S, Abdelall et al. [4] recommended Zivi’s correlation [23] as follows:equation(30)S=(ρL/ρG)1/3S=(ρL/ρG)1/3