The hydrodynamics of a dispersed air-water system within a spouted column with a concentric draft tube and a conical base is simulated using CFD based on a two–fluid Euler–Euler (E-E) modeling framework and k-ε two-equation turbulence closures. The interaction between the dispersed gas phase and the continuous liquid phase is characterized by bubble–liquid interphase forces (drag, turbulent dis...

Fluidized beds are being used in practice to gasify biomass to create producer gas, a flammable gas that can be used for process heating. However, recent literature has identified the need to better understand and characterize biomass fluidization hydrodynamics, and has motivated the combined experimental-numerical effort in this work. A cylindrical reactor is considered and a side port is intr...

The holdup problem arises when parties negotiate to divide the surplus generated by their relationship specific investments. We study this problem in a dynamic model of bargaining and investment which, unlike the stylized static model, allows the parties to continue to invest until they agree on the terms of trade. The investment dynamics overturns the conventional wisdom dramatically. First, t...

Holdup in Oligopsonistic Labour Markets: A New Role for the Minimum Wage We consider a labour market model of oligopsonistic wage competition and show that there is a holdup problem although workers do not have any bargaining power. When a firm invests more, it pays a higher wage in order to attract workers from competitors. Because workers participate in the returns on investment while only fi...

Jet loop reactors are standard multiphase used in chemical, biological and environmental processes. The strong liquid jet provided by a nozzle enforces both internal circulation of gas as well entrainment dispersion the phase. We present one-dimensional compartment model based on momentum balance that describes phase reactor. This considers influence local variations volume fraction circulation...

Abstract Based on the Euler-Euler-Lagrangian framework, Euler-Euler two-fluid model coupled with population balance (PBM) and Discrete Phase Model (DPM) were used to simulate gas-liquid-solid three phase dynamic behavior in laboratory bubble column. The non-Newtonian properties of liquid was considered numerical simulation, cases different models discussed. It is found that peak value velocity ...

The online detection of liquid flow rate in gas-liquid two-phase has become an important factor ensuring the safe operation gas wells. In this paper, real-time measurement holdup is carried out by analyzing characteristics vibration signals excited impacting on pipe wall. Firstly, acceleration sensing and processing system constructed to obtain Then, pure airflow at different velocities excitat...

The identification of the main flow regime boundaries in bubble columns is essential since the degrees of mixing and mass and heat transfer vary with the flow regime. In this work, a new statistical parameter was extracted from the time series of the cross-sectional averaged gas holdup. The measurements were performed in bubble columns by means of conductivity wire-mesh sensors at very high sam...