If granular particles are heated up, they produce thermal stresses to their confining walls. How should these storages be designed, what properties should the particles have, for causing not too high stresses on the confining walls?
Little can be said in general terms, and one would have to refer to the considerable literature on hoppers, bins, and related issues, for a detailed analysis of the particular problem being considered. Pilot plant testing, and/or computer simulation, might be also advisable, to test and optimize the actual hopper design.
I would, nevertheless, suggest paying attention to the thermal expansion coefficient of the particles. If the particles constitute a powder, it is possible to measure its dilatation coefficient at a similar packing density, using the appropriate type of sample holder. For larger particles one would have to consider the thermal expansion coefficient of the material that constitutes the particles. The hopper wall material should in principle possess a thermal expansion coefficient comparable but somewhat higher than that of the granular content. Yet, this may be not a necessary criterion, once we consider other relevant properties of the actual particles (e.g. its possible thermoplasticity).
Furthermore, it is important is to consider the possibility of aggregation or cohesion caused by heat, or even of adhesion of the particles to the hopper wall, so that adequate design solutions can be implemented to ensure a regular granular flow.
Also to be checked is the possible change of the angle of repose for the particulate material on heating.
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