One of the main barriers for the successful utilization of new biomass feedstocks in commercial pellet boilers is the lack of knowledge about the combustion behavior of such fuels, particularly in terms of ash slagging, which can potentially damage the boiler and limit combustion efficiency. The VI Framework European project Domoheat studied the combustion of 15 Mediterranean woody and herbaceous biomass fuels in commercial 60 kW domestic pellet boilers. The performance of several methods for the prediction of measured boiler slagging was tested, including ash composition-based slagging indices, standard ash initial deformation temperature (IDT), and a new slagging laboratory method, the BioSlag test, based on the sieving of the ash and slag obtained in the combustion of 250 g of fuel in a furnace at controlled temperature conditions. IDT values allowed us to identify slagging in fuels with high silica (e.g., rye straw pellet) or alkali contents (e.g., almond shell) but failed to discriminate medium slagging of fuels such as contaminated poplar chip. Slagging indices based on silica and alkali content of the ashes showed success for predicting boiler-observed slagging. The BioSlag test predicted observed slagging percentage in the boiler with R 2 = 0.87. This test could discriminate both high slagging of fuels with high Si content (e.g., rye straw pellet, pinecone seed shell) and the medium slagging tendency caused by alkali elements (e.g., almond shell, olive stone) and by moderate Si contents (e.g., contaminated poplar chip).

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The increasing use of smartphone technology in people's daily lives and its continuous development lead to the inevitable use of mobile applications because of their easy access anytime and anywhere. In this study, a new Android application for smartphones is developed and presented for the remote control of a micro‐cogeneration system from a mobile device without the need to be near the system. The mobile application consists of five different windows through which real‐time data on the most important variables of the system can be observed at any time. Additionally, the application allows the user to select the system's desired operating mode among a total of five possibilities. Alarms and warnings are also shown along with the detailed status of the main variables of the groups forming the system. Moreover, the application can graphically show the progression of variables at any time, and a history of the changes to the system is available. An experimental practice based on the “use of current mobile applications” for a subject of the Master of Thermal Engineering is proposed as a pedagogical method that involves the procedure “learning by doing,” in which students can realize the great advantages of using these technologies. © 2016 Wiley Periodicals, Inc. Comput Appl Eng Educ 24:497–507, 2016; View this article online at http://www.wileyonlinelibrary.com/journal/cae; DOI

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A detailed description of the first functional new approach to simulate the bed physics in biomass boilers in a Eulerian mathematical framework is presented. In particular, the analysis of the context of the collapse due to gravitational forces, the design of an automated algorithm that is responsible for its simulation under ANSYS‐Fluent, the concrete implementation of this algorithm, and its test with experimental contrasted data are described. The proposed solution can replicate the angle of repose of different fuels in biomass combustion boilers by implementing a series of geometric mechanisms applied to the mesh. The selected approach mainly responds to a computational efficiency requirement; both memory management and execution speed are relevant.

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