Table 3 Key drift–flux parameters in Eq. (13)

Slip between two phases

\(\gamma = S_{\text{G}}(\rho_{\text{G}}\rho_{\text{L}}\rho_{\text{m}}/\rho ^{*2}_{\text{m}})[(C_{0}-1)u_{\text{m}}+u_{\text{d}}]^{2}/(1-S_{\text{G}})\)

Mixture density

\(\rho_{\text{m}} = S_{\text{G}}\rho_{\text{G}}+(1-S_{\text{G}})\rho _{\text{L}}\)

Mixture velocity

\(u_{\text{m}} = [S_{\text{G}}\rho_{\text{G}}u_{\text{G}} + (1-S_{\text{G}})\rho_{\text{L}}u_{\text{L}}]/\rho_{\text{m}}\)

Adjusted average density of mixture

\(\rho ^{*}_{\text{m}} = S_{\text{G}}C_{0}\rho_{\text{G}}+(1-S_{\text{G}}C_{0})\rho_{\text{L}}\)