Simulation tools are important to investigate and predict mobility and the destructive potential of gravitational mass flows (e.g., snow avalanches). AvaFrame – the open avalanche framework – offers ...well-established computational modeling approaches, tools for data handling and analysis, and ready-to-use modules for evaluation and testing. This paper presents the theoretical background, derivation, and model verification for one of AvaFrame's core modules, the thickness-integrated computational model for avalanches with flow or mixed form of movement, named com1DFA. Particular emphasis within the description of the utilized numerical particle–grid method is given to the computation of spatial gradients and the accurate implementation of driving and resisting forces. The implemented method allows us to provide a time–space criterion connecting the numerical particles, grid, and time discretization. The convergence and robustness of the numerical implementation is checked with respect to the spatiotemporal evolution of the flow variables using tests with a known analytical solution. In addition, we present a new test for verifying the accuracy of the numerical simulation in terms of runout (angle and distance). This test is derived from the total energy balance along the center-of-mass path of the avalanche. This article, particularly in combination with the code availability (open-source code repository) and detailed online documentation provides a description of an extendable framework for modeling and verification of avalanche simulation tools.
Buoyant Energy is a new approach to store energy offshore in floating structures and is based on the well-established technologies of pumped-storage hydro-power. Buoyant Energy Quarters (BEQ) are a ...combination of floating city extensions with the Buoyant Energy-storage approach and are currently investigated by a multi-disciplinary team in a research project funded by the European Regional Development Fund. This paper presents some of the first advances of the project. The first part of the paper focuses on the development design criteria for floating stability and storage capacity for several standard storage geometries. The second part describes the approach for the energy system analysis. Finally, an example for a possible application, in which the BEQ storage is used to balance energy produced by photovoltaic panels with domestic electrical energy demand over the course of a few days, is presented.
