solute transport in unsaturated porous media can be viewed as a coupled phenomenon with waterand heat transport, together with mechanical behaviour of media. in this paper, solute transport is formulatedmathematically considering heat and water flow in deformable porous media. advection, dispersion anddiffusion of chemical species in the liquid phase are considered. convection and conduction fo...

Experiments were performed in a scaled annular cavity design, to investigate melt dispersal from the reactor pit when the reactor pressure vessel lower head fails at low system pressure of less than 2 MPa. In the part of the experimental program presented in this paper, the fluid dynamics of the dispersion process was studied using model fluids, water or bismuth alloy instead of corium, and nit...

For the calculation of reactive flows in bubble columns the local interfacial area is one of the key parameters. In addition backmixing causes a residence time distribution in the gas and liquid phase, thus mixing phenomena have to be considered as well. The three-dimensional, instationary flow fields in bubble columns are numerically calculated using an Euler multi-fluid model. The resulting s...

Dispersion and spreading of concentration signals in gas/liquid microreactors is studied with methods of computational fluid dynamics (CFD). It is shown that conventional reactor designs exhibit a broad residence-time distribution due to convective signal dispersion. This result is supported by experiments monitoring the transport of a liquid plug introduced into the microreactor by a microdisp...

Theoretical calculations are presented of solid-liquid equilibrium for linear quadrupolar molecules, focusing especially on the ratio of the triple point temperature to the critical temperature. The proposed treatment uses the hard quadrupolar dumbbell model as the reference system, and incorporates the effect of dispersion forces through a mean-field term. The reference system of quadrt/polar ...

The structure of liquid water has been addressed by ab initio molecular dynamics simulations based on density functional theory. Exchange-correlation effects have beed described by the popular PBE and RPBE functionals within the generalized gradient approximation as these functionals also yield satisfactory results for metals which is important to model electrochemical interfaces from first pri...

The instability of a Fermi-liquid drop with respect to bulk density distortions is considered. It is shown that the presence of the surface strongly reduces the growth rate of the bulk instability of the finite Fermi-liquid drop because of the anomalous dispersion term in the dispersion relation. The instability growth rate is reduced due to the Fermi surface distortions and the relaxation proc...