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The aim of this study is to identify key factors limiting efficiency of pumped heat energy storage systems and determine some general features of transient behavior of solid state, sensible heat storages. Moreover, it aimed at establishing a feasible approach to transient conjugate heat transfer (CHT) analyses for such applications.

A zero-dimensional analytical model is used to determine the system efficiency sensitivity to efficiency of its components. Analysis of argon gas flow in an exemplary configuration of layered bed thermal energy storage is presented. The analysis incorporates a unsteady reynolds averaged navier stokes model with conjugate heat transfer between gas and solid storage core.

It is established that exergetic efficiency of the heat storage is one of the key factors for the system’s overall performance. Three full cycles of storage charging and discharging having 17 h physical time in total are simulated, with calculation of exergetic efficiency for each of the cycles. From standpoint of the system efficiency, it is concluded that the presented heat storage kind has limited exergetic efficiency because of severe temperature drop at the solid–fluid interface in comparison to granular kind of heat storage devices. From the methodological standpoint, it is concluded that calculating the exergetic efficiency of the heat storage by direct computational fluid dynamics (CFD) analysis requires significant amount of walltime and computational resources.

The paper presents unconventional approach to using standard CFD tools by exploiting numerical diffusion to numerically suppress high-frequency solution oscillations. This strategy grants that the analysis, otherwise requiring impractically long computation walltime, is completed within a practical time.

This article seeks to introduce the concept of the Grid‐GMPLS control plane architecture with focus on new services, models, and interoperability issues of Grid‐GMPLS (G²MPLS) and GMPLS control planes. The purpose of this activity is to design, implement and test extensions of the GMPLS Control Plane that can enable the paradigm of a G²MPLS network.

The approach deploys extended GMPLS implementations aiming to facilitate bandwidth provisioning to Grid users.

G²MPLS is a Network Control Plane architecture that implements the concept of Grid Network Services. GNS is a service that allows the provisioning of network and Grid resources in a single‐step through a set of integrated procedures. By providing a unified network/Grid infrastructure the control plane can adapt to the demands of applications having intensive requirements on both computational and network resources.

The project delivers the prototype implementation of G²MPLS. Consideration should be given to involving the vendors of the optical equipment in the development process to incorporate the project findings into their operating systems.

The G²MPLS protocol stack has been designed to be compatible with the ASON/GMPLS architecture. This could lead to possible integration of Grids in the existing operational networks, by overcoming the current limitations of Grids running over dedicated networks with their own administrative procedures.

The paper provides the description of Grid Network Infrastructures with a common and transversal Control Plane approach based on G²MPLS, in which Grid resources and optical network resources are both controlled by the same Control Plane, seamlessly spanning the different Control and Management domains of the network.