Juan Wang

CFD Simulation of Flash Boiling of Supercritical Pentane during Asphalt Granulation

We consider a technology for granulation of asphalt from its mixture with supercritical pentane and construct a mathematical model for the process. We compare two nozzle designs intended for spraying the mixture and flash boiling of pentane. We show that a nozzle with a conical section is not susceptible to clogging by the asphalt. The pentane vaporization rate and the fraction of vapor phase increase owing to the presence of the asphalt phase.

Experimental and numerical study on the flow behavior in a jet-driven swirling flow

ABSTRACT In order to understand the asphalt separation processes in a new technique of solvent deasphalting, the hydrodynamics of the jet-driven swirling flow within a spray granulation tower (SGT) was studied by using experimental and numerical methods. Mean velocity components were measured by use of the Phase Doppler Particle Anemometer (PDPA). Simulation with Reynolds Stress Model (RSM) was carried out to understand the flow information. Two different zones in the jet-driven swirling flow were observed in both experiment and simulation. A combined effect of jet, jet entrainment and jet interactions leads to complex flow behavior in the upper part. A double swirling flow was identified on the basis of the tangential and the axial velocity distribution in the lower part. The specific flow pattern was identified based on the experimental and computational flow field. An empirical formula was proposed to predict the percentage of the SGT occupied by the jet and the swirl zone.

Dynamic Simulation of Flow Behavior in a New Spray Granulation Tower

Aiming to understand the asphalt granulation and separation processes in a new technique of solvent deasphalting, this work performs a detailed numerical study of the gas flow behaviors in a spray granulation tower with array nozzles. The influence of nozzle distances and jet angles on the fluid dynamics of the tower, especially on the double swirling flow, is investigated. The simulation results reveal many interesting phenomena, which include a flow consisting of two distinct regimes, a multistage flow development of jet array and a strong dependence of the velocity distribution on the nozzle arrangement.

Simulation of Bubbles Aggregation Process Base on Interface Compression Method

Interface compression method is a VOF model presented in recent years. In this paper, the difference between interface compression method and classic acceptor-donor methods was revealed. The advection test shown the interface compression method was more accurate than HRIC scheme. The bubble aggregation process was simulated by this method using open source CFD tool OpenFOAM. Simulation shown the method can accurately capture the interface in the process of bubble aggregation and the loop flow is a key factor in the process.