Pushing Droplet Through a Porous Medium

I use a mechanical model of a soft body to study the dynamics of an individual fluid droplet in a random, non-wettable porous medium. The model of droplet relies on the spring–mass system with pressure. I run hundreds of independent simulations. I average droplets trajectories and calculate the averaged tortuosity of the porous domain. Results show that porous media tortuosity increases with decreasing porosity, similar to single-phase fluid study, but the form of this relationship is different.

Heat and mass transfer in a metal hydride reactor: combining experiments and mathematical modelling

Heat transfer in porous metal hydride (MH) beds determines efficiency of MH devices. We present a COMSOL Multiphysics numerical model and experimental investigation of heat and mass transfer in a MH reactor filled with 4.69 kg of AB5 type alloy (Mm0.8La0.2Ni4.1Fe0.8Al0.1). To achieve an agreement between the model and experiments it is necessary to include a flow control device (inlet valve or flow regulator) into the model. We propose a simplified and easy-to-calculate boundary condition based on a porous domain with variable permeability at reactor inlet. The permeability of the domain is connected with hydrogen mass flow by a PID controller. Thus, boundary conditions for the inlet pressure and mass flow are coupled and heat transfer inside the reactor could be calculated without additional assumptions applied to heat and mass transfer in the MH bed.

Insights into the poroelastic mechanical behaviour of a crystalline magma reservoir and its influence on modelling volcano surface deformation

<p><span xml:lang="EN-US"><span>Understanding the physical properties of magma reservoirs and their fluid/mechanical behaviour is crucial for improving geophysical models. New evidence suggests that large bodies of magma are difficult to maintain for an extended time period and that melts may instead reside within crystal-</span><span>mush</span><span> reservoirs which consist of variably packed frameworks of crystals and interstitial melt. Most existing volcano deformation models assume a pressurized cavity embedded in a homogeneous or heterogenous elastic half-space and therefore ignore the presence of crystals and the possible poroelastic mechanical response to melt intrusion or withdrawal. Here, we consider the magma reservoir to be entirely porous, comprising melt distributed between solid crystals. We investigate the influence of poroelastic mechanical behaviour on reservoir pressure development and resultant </span></span><span xml:lang="EN-US"><span>spatio</span></span><span xml:lang="EN-US"><span>-temporal surface deformation. We examine the post-intrusion and post-eruption time-dependent pressure evolution in the magma reservoir due to melt diffusion in the porous domain. Unlike the classic (cavity) models for volcanic surface deformation, an observable post-eruptive or post-intrusion time-dependent inflation can occur without an additional mass change if the reservoir is sufficiently permeable. Post-intrusion and post-eruption timescales vary depending on the porosity of the </span><span>mush</span><span> (melt fraction), permeability and magma viscosity. Our study confirms that reservoir inflation and surface deformation can occur without an intrusion or withdrawal of melt but are instead controlled by the </span><span>mush</span><span>'s poroelastic behaviour</span></span><span xml:lang="EN-US"><span>.</span></span><span xml:lang="EN-US"><span> </span></span></p><p> </p>

NUMERICAL INVESTIGATION OF FLUID FLOW INSTABILITIES IN PORE-SCALE WITH HETEROGENEITIES IN PERMEABILITY AND WETTABILITY

Quadrant geometry with permeability and wettability contrast occurs in different events, such as faults, wellbore damage, and perforation zones. In these events, understanding the dynamics of immiscible fluid displacement is vital for enhanced oil recovery. Fluid flow studies showed that viscous fingering occurs due to viscous instabilities that depend on the mobility of fluids and capillary forces. Besides, the porous domain heterogeneity is also effective on the formation of fingering. So, the purpose of the current research is to numerically investigate the effect of heterogeneity in wettability and permeability, and flow properties in Saffmann-Taylor instabilities. Numerical simulations with different flow rates in the permeability contrast model illustrated the nodal crossflow, growth of viscous fingering in the nodal part, and bypass flow in the second zone. In the wettability contrast model, a capillary fingering pattern is observed and fluid patches are isolated because of capillary force and the end effects are trapped within the quadrant. Moreover, the consequences of wettability on apparent wettability that alters the fluid-front pattern and displacement efficiency are shown.

Micro-Computed Tomography Pore-Scale Study on Natural Convection in a Cubic Cavity Filled With Complex Porous Medium

A pore-scale numerical simulation was carried out in this study to predict the natural convection in a cubic cavity filled with reconstructed porous medium using lattice Boltzmann Method (LBM). The computational porous domain was established with the micro-computed tomography technique. The natural convection phenomena were predicted with the pore-scale simulation for different thermal boundary conditions and fluid thermal properties. The results show that the natural convection in the present porous domain is more obvious as the side wall is heated compared to that as the bottom wall is heated. The existence of porous structure suppresses the natural convection in the cubic cavity. As Rayleigh number increases, the natural convection in the porous domain is enhanced accordingly. The heat flux distribution on the porous structure surface varies intensively due to the complex flow characteristic in the small pore spaces. The numerical approach presented in this study is to provide a promising solution that can simulate pore-scale natural convection in porous medium and can be further extended for the development of field-scale model for transport processes in porous medium.

Performers’ discourses on listening to recordings

How we listen to music and respond to its media and contexts has changed significantly since the invention of sound recording. Today’s musicians have countless opportunities to listen to others’ interpretations given the vast availability of past and contemporary repertories through the global reach of recordings. This study investigated the extent to which the growing archive of recordings provides a valuable resource for performers’ creativity. Although musical performance is a particularly porous domain for influence through either deliberate or spontaneous assimilation of expressive variation from other aural sources, little empirical research exists on influence in performance and specifically on the influence of recordings. Qualitative data were obtained via an online questionnaire to identify how and in what ways the use and influence of recordings have changed over the course of classical performers’ training or professional careers. Respondents’ ( N = 130) comments were analysed using a thematic inductive approach. The emerging themes reveal an overall increased level of use of recordings now relative to the past, a largely positive contribution of recordings in shaping musical development, including the role of recordings in self-regulated learning, a largely positive attitude to the influence of others’ interpretations, a means of developing expressions of self-identity in relation to others and a route to acquiring a more critical and discerning mode of listening to recordings. Implications for music education are discussed in terms of how listening to recordings, in both formal and informal learning contexts, could support advanced musicians’ learning through trial and error, enhance creative insight, strengthen self-efficacy, foster metacognitive skills and nurture individuality.