Turbulence, heat and mass transfer 2: Proceedings of the second international symposium on turbulence, heat and mass transfer. Delft, The Netherlands, June 9-12, 1997

Simulating compressibility in cavitating flows with an incompressible mass transfer flow solver

The effect of finite mass transfer rate in combination with temporal resolution on the dynamics of caviting flows is subject of this study. It will be shown that global flow quantities exhibit convergent behaviour with respect to mass transfer rate and time step size in incompressible pressurebased simulation of cavitating flows. It is concluded...

Interfacial interactions and mass transfer at the interfacial region of bituminous hydrocarbon mixtures

The adhesion between bitumen and aggregate is a complex process with numerous of variables. To improve the understanding of the bond between bitumen and aggregates in road applications, this research focuses on preferential adsorption, which is one aspect of bitumen-aggregate adhesion. The main objective is to find out whether there is...

Detailed simulations of liquid and solid-liquid mixing: Turbulent agitated flow and mass transfer

This thesis aims at a contribution to reliable and accurate predictions of complex, multi-phase processes. The reader is presented detailed simulations on liquid and solid-liquid mixing using large eddy simulations (LES) including scalar mixing and particle transport in a Rushton turbine stirred tank geometry. Large eddy simulations have been...

Fluidized bed ice slurry generator for enhanced secondary cooling systems

Ice slurries are liquid solutions of a freezing point depressant in water, in which small ice crystals are present. Ice slurries are efficient secondary cooling fluids because they utilize the latent heat effect involved with the ice/water phase change. A high heat capacity is available at relatively constant temperatures, while ice slurries are...

Forced convection mass deposition and heat transfer onto a cylinder sheathed by protective garments

In chemical, biological, radiological, and nuclear protective clothing, a layer of activated carbon material in between two textile layers provides protection against hazardous gases. A cylinder in cross flow, sheathed by such material, is generally used to experimentally test the garment properties. This is, however, complicated and predictive...

Transport of heat and mass in a two-phase mixture: From a continuous to a discontinuous description

We present a theory that describes the transport properties of the interfacial region with respect to heat and mass transfer. Postulating the local Gibbs relation for a continuous description inside the interfacial region, we derive the description of the Gibbs surface in terms of excess densities and fluxes along the surface. We introduce...

The effect of interface movement and viscosity variation on the stability of a diffusive interface between aqueous and gaseous CO2

Carbon dioxide injected in an aquifer rises quickly to the top of the reservoir and forms a gas cap from where it diffuses into the underlying water layer. Transfer of the CO2 to the aqueous phase below is enhanced due to the high density of the carbon dioxide containing aqueous phase. This paper investigates the behavior of the diffusive...

Analysis of coupled mass transfer and sol-gel reaction in a two-phase system

The coupled mass transfer and chemical reactions of a gel-forming compound in a two-phase system were studied in detail. Tetra-methyl-ortho-silicate (TMOS) is often used as a precursor in sol-gel chemistry to produce silica gels in aqueous systems. TMOS can also be mixed with many hydrocarbons without chemical reaction, which allows for various...

Resistances for heat and mass transfer through a liquid–vapor interface in a binary mixture

In this paper we calculate the interfacial resistances to heat and mass transfer through a liquid–vapor interface in a binary mixture. We use two methods, the direct calculation from the actual nonequilibrium solution and integral relations, derived earlier. We verify, that integral relations, being a relatively faster and cheaper method, indeed...

Predicting the Liquid Phase Mass Transfer Resistance of Structured Packings

Published correlations for estimating the liquid phase mass transfer coefficients of structured packings are compared using experimental evidence on the efficiency of Montz-Pak B1–250MN and B1–500MN structured packings as measured in total reflux distillation tests using the chlorobenzene/ethylbenzene system at two operating pressures. Large...

Nonequilibrium thermodynamics of interfaces using classical density functional theory

A vapor-liquid interface introduces resistivities for mass and heat transfer. These resistivities have recently been determined from molecular simulations, as well as theoretically using the van der Waals square gradient model. This model, however, does not allow for direct quantitative comparison to experiment or results from molecular...

Numerical Simulation of Natural Convection in Heterogeneous Porous media for CO2 Geological Storage

We report a modeling and numerical simulation study of density-driven natural convection during geological CO2 storage in heterogeneous formations. We consider an aquifer or depleted oilfield overlain by gaseous CO2, where the water density increases due to CO2 dissolution. The heterogeneity of the aquifer is represented by spatial variations of...

The role of temperature in nucleation processes

Heat and mass transfers are coupled processes, also in nucleation. In principle, a nucleating cluster would have a different temperature compared to the surrounding supersaturated old phase because of the heat release involved with attaching molecules to the cluster. In turn a difference in temperature across the cluster surface is a driving...

Mass transfer limitations in binderless ZSM-5 zeolite granules during adsorption of flavour compounds from aqueous streams

BACKGROUND: Recently, a new process concept has been proposed to selectively adsorb wort off-flavours, i.e. aldehydes, from alcohol-free beers with hydrophobic zeolites. RESULTS: In this work, we investigated the uptake of a mixture of wort flavour compounds (2-methylpropanal, 2-methylbutanal, 3-methylbutanal, furfural, and methional), from a...

Membrane bioreactors for syngas permeation and fermentation

Syngas fermentation to biofuels and chemicals is an emerging technology in the biobased economy. Mass transfer is usually limiting the syngas fermentation rate, due to the low aqueous solubilities of the gaseous substrates. Membrane bioreactors, as efficient gas–liquid contactors, are a promising configuration for overcoming this gas-to...