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A magnetic refrigeration test device has been built and tested. The device allows variation and control of many important experimental parameters, such as the type of heat transfer fluid, the movement of the heat transfer fluid, the timing of the refrigeration cycle, and the magnitude of the applied magnetic field. An advanced two-dimensional numerical model has previously been implemented in order to help in the optimization of the design of a refrigeration test device. Qualitative agreement between the results from model and the experimental results is demonstrated for each of the four different parameter variations mentioned above.

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The active magnetic regenerator (AMR) refrigeration system represents an environmentally attractive alternative to vapour-compression refrigeration. This paper compares the results of two numerical AMR models: (1) a 1D finite difference model and (2) a 2D finite element model. Both models simulate a reciprocating AMR and can determine the cyclical steady-state temperature profile of the system as well as performance parameters such as the refrigeration capacity, the work input and the coefficient of performance (COP). The models are used to analyse an AMR with a regenerator made of flat parallel plates of gadolinium operating in the presence of a 1 T magnetic field. The results are used to discuss under which circumstances a 1D model is insufficient and a 2D model is necessary. The results indicate that when the temperature gradients in the AMR perpendicular to the flow are small a 1D model obtains accurate results of overall results such as the refrigeration capacity but that a 2D model is required for a detailed analysis of the phenomena occurring inside the AMR.

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The present study is an attempt to explain the reason for the sinking of the scour protection observed at Horns Rev 1 Offshore Wind Farm. A new method for analyzing the survey data has been developed based on detailed descriptions in the literature of the processes causing sinking. The results of the analysis of the survey data have shown that the largest relative damage was observed at shallow water and for the largest scour protections. This is foundbased on descriptions found in the literatureto be characteristic for sinking in wave dominated climate and as the current at Horns Rev is found to be too weak to mobilize the sediment underneath the scour protections, it is found likely that the waves had a major influence on the sinking of the scour protections at Horns Rev 1 Offshore Wind Farm.