This study deals with the erosion of granular laboratory dykes to allow for the prediction of the main dyke failure features, including the temporal advance of the maximum dyke height and the breach discharge. Two extreme scenarios are considered: (1) constant approach flow discharge; and (2) constant headwater elevation during the breach process, as the two extreme cases of prototype scenarios. Based on the previous research, the effects of three additional parameters, namely the up-and downstream dyke face slopes and the crest length, are considered by the so-called dyke shape parameter. Its effect is included in the governing dyke breach equations so that all relevant variables vary only as a function of discharge scenario, original dyke height, and sediment diameter. The breach process is described with typical images and plots, to highlight the various effects. The results allow for an estimate of the dyke breach characteristics based on Froude similitude.

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The numerically stable simulation of cavitation effects is mandatory for predicting the friction and wear behavior of translational hydraulic seals. This contribution provides a comparison of two different implementations of the Jakobsson-Floberg-Olsson (JFO) cavitation model, an investigation of their properties and possible options for their stabilization. These methods are tested and compared both within a simple divergent gap test case as well as within an EHL simulation of a rubber metal contact. Based on these comparisons and theoretical investigations, the strengths and weaknesses of the different methods are summarized and discussed with respect to an application in EHL simulations of translational hydraulic seals.

Reducing the carbon emissions from hotels on non-interconnected islands (NII) is essential in the context of a low carbon future for the Mediterranean region. Maritime tourism is the major source of income for Greece and many other countries in the region, as well as hot-temperate and tropical regions worldwide. Like many NIIs, Rhodes attracts a high influx of tourists every summer, doubling the island’s energy demand and, given the high proportion of fossil fuels in the Rhodian energy supply, increasing carbon emissions. Using the theoretical framework ‘FINE’, this paper presents the optimisation of a medium-sized hotel’s energy system with the aim of reducing both cost and carbon emissions. By introducing a Photovoltaic (PV) net metering system, it was found that the carbon emissions associated with an NII hotel’s energy system could be reduced by 31% at an optimised cost. It is suggested that large-scale deployment of PV or alternative renewable energy sources (RES) in NII hotels could significantly reduce carbon emissions associated with the accommodation sector in Greece and help mitigate climate change.