Correlations for the Interphase Drag in the Two-Fluid Model of Gas--Liquid Flows through Packed-Bed Reactors

Experiments conducted by NASA measured the pressure drop due to gas–liquid flow through a packed-bed reactor under microgravity conditions. From these experiments, we develop correlations for the gas–liquid $f_{gl}$ interphase drag in a two-fluid model (TFM). We use an Ergun-type closure for liquid–solid drag. Then, under a 1D flow assumption, $f_{gl}$ is the only unknown in the TFM. Using a data-driven approach, we determine $f_{gl}$ and correlate it (via composite fits) with the liquid and gas Reynolds numbers, $R{e}_l$ and $R{e}_g$, respectively, and the Suratman number $S{u}_l$. To validate the proposed $f_{gl}(R{e}_l,R{e}_g,S{u}_l)$ closure, we perform two-dimensional transient simulations at microgravity conditions using ANSYS Fluent and employing an Euler–Euler formulation. We find good agreement between the simulations based on the proposed $f_{gl}$ closure and the experimental data.