Articles techniques et présentations

NASA's Advanced Exploration Systems (AES) program is pioneering new approaches for rapidly developing prototype systems, demonstrating key capabilities, and validating operational concepts for future human missions beyond Earth orbit" [1]. Under the new Atmosphere Revitalization Recovery ... En savoir plus

Sedimentation is a challenging two-phase problem to model and simulate. Many applications in the industry use sedimentation for separation. For example treatment of wastewater often carried out in settling basins. Different types of the sedimentation process include independent and zone ... En savoir plus

The most successful nanofiltration models are those based on the combination of the Extended Nernst-Planck equation with the Donnan steric equilibrium. These models have been typically solved by using iterative procedures based on the Runge-Kutta method. Yet, such procedures present ... En savoir plus

Most reactor designs are based on pseudo homogeneous models. This paper studies the COMSOL simulation of a packed bed reactor using a 2-D heterogeneous model. The case considered was a packed reactor with spherical catalyst for oxidation of o-xylene in air to phthalic anhydride. Large ... En savoir plus

Fluidized Catalytic Cracking (FCC) regenerators utilize a fluidized bed to facilitate catalyst regeneration. Cyclones are used to separate the catalyst from the gas stream and return the catalyst to the fluidized bed; as the gas progresses through the system for further processing. This ... En savoir plus

Steam Reforming of Ethanol using a Catalytic Wall Reactor (CWR) was successfully studied using COMSOL Multiphysics. A mathematical model was used to describe the reactor performance in terms of the main variables and dimensionless groups. Simulations showed that at specified conditions ... En savoir plus

Chlorine reactor is used to dry molten LiCl-KCl eutectic salt before it is put to use in electrorefining operation. Molten salt electrorefining is a pyrochemical method of separation of heavy elements from spent metallic nuclear fuel. It is a high-temperature process which uses molten ... En savoir plus

The dependency of electrochemical processes performances on mass transfer is well-known. Electrolyte flow in the vicinity of electrodes surface can enhance reactions due to increased mass transfer. This flow can be generated by the production of a gaseous phase, leading to a natural ... En savoir plus

Some NASA efforts are focused on improving current systems that utilize fixed beds of sorbent pellets by evaluating structured sorbents, seeking more robust pelletized sorbents, and examining alternate bed configurations to improve system efficiency and reliability. For the bulk ... En savoir plus

The paper presents and compares two models for simulating magneto-hydrodynamic flow of RedOx electrolyte in a conduit patterned with circular pillars. The first model solves the coupled Nernst-Planck and Navier-Stokes equations subjected to Butler-Volmer electrode kinetics and provides ... En savoir plus