Fluidity of particles in an enclosure

摘要

Subject of the invention is how to influence fluidity of solid particles e.g. the behaviour of particles in a so called bean bag mattress. It comprises a bean bag mattress contained by a flexible support structure with inclined walls. Means are provided of regulating the amount of air in the bag. The mattress has been shown to offer relief to patients, bedridden for long periods and prevent the occurrence of bed sores.