2. Properties of individual particles

2.1 Equivalent sizes and diameters

As we have just stated, as soon as we move away from a perfectly regular shape, the notion of size has no absolute physical meaning. To get round this problem, it's common practice to represent the characteristic length of a particle by an equivalent size. The latter is defined as a function of :

• the intended use of the information. In fact, the characteristic size must be chosen judiciously according to the intended application (fluidization, storage, transport, separation, etc.), just as an individual would not give the same answer if asked for his size, depending on whether he was looking for shoes, a shirt, a hat, pants, a belt, etc;

• what the analysis instrument can...