Benchmark of Delayed Equilibrium Model (DEM) and classic two-phase critical flow models against experimental data

Application of a fast transonic trajectory determination approach in 1-D modelling of steady-state two-phase carbon dioxide flow

“…DEM results compared with HEM predictions: The DEM correlation constants presented in eq. (9) were adjusted on the base of the Super Moby Dick experiment simulations described for instance in [13]. In the simulations, the model has been supplemented with Darcy friction factor calculated on the base of the Lockhart-Martinelli (LM) parameter and the flow was treated as adiabatic [13].…”

“…(9) were adjusted on the base of the Super Moby Dick experiment simulations described for instance in [13]. In the simulations, the model has been supplemented with Darcy friction factor calculated on the base of the Lockhart-Martinelli (LM) parameter and the flow was treated as adiabatic [13]. As a first step of the present investigation, calculations of all 10 runs of CO 2 flow cases presented in [8] were carried out with described DEM original setup.…”

“…This section presents only crucial elements of the analysis which are necessary to describe the basis of the applied solution procedure. The proposed methods require some information that can be obtained by applying the Possible-Impossible Flow algorithm that was presented in [11,13].…”

“…However, under real operation conditions, both mechanical and thermal non-equilibrium exist simultaneously making strong difficulties to accurately predict critical mass flow rate through the motive nozzle. This problem was widely investigated [7,[11][12][13] and it was proved that most physically consistent predictions may be obtained from models that take into account the thermal none-equilibrium e↵ects. Two of such kind models (HRM and DEM) together with Homogeneous Equilibrium Model and lumped parameter approach of Moody and Hanry-Fauske were investigated in [14].…”

Critical flow prediction by system codes – Recent analyses made within the FONESYS network

“…For this reason, results from SMD and BNL tests were also compared against the predictions of the 1-D Delayed Equilibrium Model (DEM) for critical flow rate in steady state or quasi-steady state conditions developed by UCL (Bartosiewicz et al, 2011;Bartosiewicz and Seynhaeve, 2014;De Lorenzo et al, 2017), not yet implemented in industrial version of SYS-TH codes. Fig.…”