I have been working in composites for sometime now. In the literature I have found that the words "Representative Volume Element" (RVE) and "Unit Cell" (UC) are used frequently. Some authors treat them differently and some treat them same. I am little bit confused can anyone PLEASE clarify the situation or suggest some good papers to read.
Thanks In Advance.
RVE and unit cell
Hi,
RVE and unit cell are actually the same. They both refer to a material point of interest where the local behavior is simulated. There is a slight catch, though. A RVE is supposed to be "representative", i.e. the volume element must be representative of the entire material. A unit cell on the other hand does not have to be representative. For e.g. in the case of polycrystal simulation in metal plasticity, a unit cell built up of 100 grains is assumed to be representative of the material behavior and is hence a RVE, whereas a unit cell with 10 grains, for e.g., is not representative and is referred to as a unit cell only and not as a RVE.
RVE and unit cell
RVE is not necessarily a unit cell and vice versa. RVE stands for a Representative Volume Element, that is a smallest piece of material that on given level of localization can be considered stuctureless.
I have been modeling porous materials for some time using unit cell approach. In some cases such as materials with non uniform mesostructure, a RVE consists of 5 to 10 unit cells with different geometries. Another good example is stucture discretisation using voronoi cells.
I would suggest you to read something on Cellular Solids Theory from Lorna Gibson. You can generally find some infos in books on continuum damage mechanics.