Defining Temperatures of Granular Powders Analogously with Thermodynamics to Understand the Jamming Phenomena

摘要

For the purpose of applying laws or principles originated from thermalsystems to granular athermal systems, we may need to properly define thecritical temperature concept in granular powders. The conventionalenvironmental temperature in thermal systems is too weak to drive movements ofparticles in granular powders and cannot function as a thermal energyindicator. For maintaining the same functionality as in thermal systems, thetemperature in granular powders is defined analogously and uniformly in thisarticle. The newly defined granular temperature is utilized to describe andexplain one of the most important phenomena observed in granular powders, thejamming transition, by introducing jamming temperature and jamming volumefraction concepts. The predictions from the equations of the jamming volumefractions for several cases like granular powders under shear or vibration arein line with experimental observations and empirical solutions in powderhandlings. The goal of this article is to establish similar concepts ingranular powders, allowing granular powders to be described with common laws orprinciples we are familiar with in thermal systems. Our intention is to build abridge between thermal systems and granular powders to account for manysimilarities already found between these two systems.