Abstract

The behaviour of granular materials is known to be strongly affected by the granular temperature, which is a measure of the intensity of particle vibration. However, no experimental technique exists to measure the granular temperature and its variation inside arbitrary media during deformation. Here, we present a new experimental technique for measurement of this granular temperature field by tracking tracer particles over time, using X-ray radiography with two simultaneous orthogonal source/detector pairs. We show that errors in particle tracking lead to systematic measurement biases. The main sources of these biases are identified and methods for their quantification are developed so that unbiased results can be calculated. The new granular thermometry technique is validated against discrete element simulations. Finally, an experimental example is shown for the case of a vibro-fluidised system, where we find that the granular temperature is highest at the free surface.

Graphical Abstract

中文翻译：

---

颗粒温度计

摘要

已知粒状材料的性能受粒状温度的强烈影响，粒状温度是颗粒振动强度的度量。但是，不存在实验技术来测量变形过程中任意介质内部的颗粒温度及其变化。在这里，我们介绍了一种新的实验技术，该技术通过使用随两个同时出现的正交放射源/检测器对进行X射线射线照相，随着时间的推移跟踪示踪剂粒子，来测量该颗粒温度场。我们证明了粒子跟踪中的误差会导致系统的测量偏差。确定这些偏差的主要来源，并开发量化方法，以便可以计算出无偏差的结果。新的颗粒测温技术已针对离散元素仿真进行了验证。最后，

图形概要