The Profound Unravelling of Equilibrium Thermodynamics and Arrhenius First-Order Kinetics in Relation to Metal Hydride Desorption Reactions

<div> <p>Approaching the entanglement problem of kinetics with thermodynamics in reversible metal hydride desorption reactions by means of a hyperbola template such as the Michaelis-Menten curve renders a closed solution for their unravelling possible, revealing profound insight of general significance into both, the structure of the rate-limiting thermodynamic factor and the nature of experiment-specific first-order Arrhenius kinetics. As by-product an alternate method of extreme simplicity for modelling transient behaviour of reversible metal hydride tanks is obtained. This paper concludes a series of works concerned with objectively approaching metal hydride soprtion reaction kinetics.</p></div>

The Profound Unravelling of Equilibrium Thermodynamics and Arrhenius First-Order Kinetics in Relation to Metal Hydride Desorption Reactions

<div> <p>Approaching the entanglement problem of kinetics with thermodynamics in reversible metal hydride desorption reactions by means of a hyperbola template such as the Michaelis-Menten curve renders a closed solution for their unravelling possible, revealing profound insight of general significance into both, the structure of the rate-limiting thermodynamic factor and the nature of experiment-specific first-order Arrhenius kinetics. As by-product an alternate method of extreme simplicity for modelling transient behaviour of reversible metal hydride tanks is obtained. This paper concludes a series of works concerned with objectively approaching metal hydride soprtion reaction kinetics.</p></div>

Implementation of the Onsager Theorem to Evaluate the Speed of the Deflagration Wave

While considering the deflagration regime, the thermal theory of combustion proposes that the mechanism of heat transfer from the flame exothermic zone to the front neighborhood reactants layer dominates the flame behavior. The introduction of the Fourier law allows a closed solution of the continuity and energy conservation equations to yield the burning velocity. It is, however, clear that this classical solution does not conform to the momentum equation. In the present work, instead of introducing the Fourier law, we suggest the introduction of a simplified version of the Onsager relationship, which accounts for the entropy increase due to the heat transfer process from the front layer to its successive layer. Solving for the burning velocity yields a closed solution that also definitely conforms to the momentum equation. While it is realized that the pressure difference across the flame front in the deflagration regime is very small, we believe that violating the momentum equation is intolerable. Quite a good fitting, similarly to the classic theory predictions, has been obtained between our predictions and some experimentally observed values for the propagation flame deflagration velocity, while here, the momentum equation is strictly conserved.

Modeling and simulation of Electromagnetic Fields on a Floating Aluminium

The electromagnetic field calculation for a floating aluminum disc is difficult to calculate since the equation involved does not produce a closed solution. The numerical, analytical, semi-analytical techniques that are already developed to find these magnetic fields have no proper mathematical formulation when the disc is disturbed from its coaxial position. The stabilization of disc is going to be effected when the disc moves away from its coaxial position due to a change in inductance between the disc and coils, due to change in magnetic flux linkage, etc. In this paper, a 2D FEM model is developed to determine the magnetic fields on a floatingaluminum disc when it is moved away from its coaxial position. The 3D FEM model developed is simulated in both COMSOL-Multiphysics and ANSYS-Electronics. The results obtained by simulation are compared, for accuracy, with the numerical solution developed earlier using Finite Difference method (FDM) and also discussed.

On quantum-mechanical equations of motion in representation dependent of external sources

In the present paper, we consider in detail the aspects of the Heisenberg’s equations of motion, related to their transformation to the representation dependent of external sources. We provide with a closed solution as to the variation-derivative motion equations in the general case of a normal form (symbol) chosen. We show that the action in the path integral does depend actually on a particular choice of a normal symbol. We have determined both the aspects of the latter dependence: the specific boundary conditions for virtual trajectories, and the specific boundary terms in the action.

Determination of Overhead Power Line Cables Configuration by FEM and Meshless FDM

The paper addresses numerical modeling of overhead power line cables subjected to static loads. Cable extensibility, their large 3D displacements as well as an interaction with strings of insulators and elastic towers are considered. A 2D exact closed solution available for certain type of loading was generalized by us to a 3D displacement case and applied as one of the benchmarks, that were used in convergence, efficiency and accuracy studies of numerical methods to select the most reliable one. Various formulations of the problem (strong and weak in both the Bubnov and local Petrov–Galerkin MLPG-5 versions) as well as various solution approximation approaches were examined, namely the finite element method (FEM) with the higher order shape functions as well as for the first time the meshless finite difference method (MFDM). Validation done by comparison of the numerical results with in situ measurements confirmed that the assumed models are reliable.